CN202483074U - Composite-structure pre-stress-stored rib - Google Patents

Abstract

The utility model discloses a pre-stored stress tendon in a composite structure. In order to solve the limitations of the existing pre-tensioning method and post-tensioning prestressing technology and make up for the problems of the existing pre-stressing technology in the aspect of reinforcing bars, the tendon is made of external The tension-compression balance body formed by the pipe and the mandrel or the inner pipe is bonded and anchored, and a heating element is arranged in the tension-compression balance body. The bonding strength of the adhesive or the strength of the mandrel is controlled by the temperature rise of the heating element. When the pre-stored stress tendons of the composite structure are laid into the target body, the heating element raises the temperature, so that the mandrel can no longer provide support for the outer tube, causing the outer tube to shrink or elongate, breaking the tension-compression balance of the original structure. Apply precompression stress or pretension stress to the target body through the bonding force between the outer tube and the target body base material, so that the outer tube and the target body form a new tension-compression balance body, that is, the prestress stored in the pre-stored stress tendons of the composite structure Released into the target body, prestressing the target body.

Description

Composite structure pre-existing stress tendons

technical field

The utility model relates to a pre-stored stress tendon of a composite structure capable of providing pre-stress to a target body, having functions of storing pre-stress and controlled release of pre-stress, a manufacturing method and a pre-stress release technique. the

Background technique

Prestressing technology brings good durability, crack resistance, water resistance, impact resistance and other advantages to structures and components, so prestressing technology has been widely used in various engineering structure fields in the world. Its applications include railway bridges, highways, storage tanks, hydraulic structures, airport runways, marine structures, nuclear power plant containment and other places that require prestressing. the

There are two commonly used prestressing techniques: pre-tensioning and post-tensioning. The common point of both is that the stress obtained after the prestressed tendon is mechanically stretched is directly applied to the component, which requires the presence of the machine and the component at the same time. The implementation of the pre-tensioning method requires a pedestal or formwork. Because the pre-tensioning method linearly arranges the reinforcement, the main tensile stress at the beam end cannot be reduced, which limits the structural force. Although the pretensioning method of folded line arrangement has been used in engineering, which has improved the mechanical performance of the structure, but the flexibility of the curved reinforcement is far from enough. The post-tensioning method requires pre-embedded pipes and anchors. Although the path direction of the prestressed tendons can be arranged according to the stress distribution, if the arc of the path of the prestressed tendons is too large, when the prestressed tendons are stretched, the prestressed tendons and the pipe If the friction force is too large, the loss of prestress is very large, which makes it difficult to implement prestress. Therefore, the post-tensioning method is not flexible enough in terms of reinforcement. the

Regardless of the pre-tensioning method or the post-tensioning method, the stress of the entire bundle of prestressed tendons in tension is equal, so the stress applied to the structure and components is also equal. When the structure and components are under stress, the stress of each section along the path of the prestressed tendon changes, but the pretensioned and post-tensioned prestressed tendons cannot apply prestress with the stress of each section of the structure and components, so They cannot better improve the mechanical performance of the structure. When the prestressed tendons are arranged in complex curves such as spirals and waves, the traditional pre-tensioning and post-tensioning methods cannot be used at all. It is very difficult to implement multi-directional and large-area prestressing, and it is also difficult to implement concrete structures that require high crack resistance, water resistance, durability, and corrosion resistance in large areas. the

People think of using fiber reinforcement to solve problems such as crack resistance, durability and corrosion resistance of structures and components. Such as fiber-reinforced concrete, fiber-reinforced ceramics and other fiber-reinforced composite materials. However, due to the inherent defects of low elongation of concrete and ceramics, it is difficult to solve the problem of brittle cracking even with high-strength, high-elastic-modulus inorganic fibers such as carbon fibers and silicon carbide fibers. The reason is that before the cracking of brittle materials such as concrete or ceramics, the stress in the fiber is very small, and it is far from reaching its own strength. Therefore, it is difficult to solve the durability and safety of structures and components without prestressed fibers. However, organic fibers with high strength but insufficient elastic modulus are more difficult to solve the brittle cracking problems of concrete or ceramics. Therefore, it is difficult to solve the durability and safety of structures and components without prestressed fiber reinforcement. the

Utility model content

In order to overcome the limitations of the existing prestressing technology, the utility model aims to provide a composite structure pre-stored stress tendons, the stress tendons themselves can store prestress, this method can increase the flexibility and simplicity of prestress reinforcement, and more Improve the mechanical performance of the structure; solve the problem of low elongation of the reinforcement without prestressed fibers or fiber bundles, and increase the toughness of brittle materials. Solve the problem that the previous prestressing technology is difficult to implement in multi-directional prestressing and large-area body prestressing, and improve the ability of prestressing technology to be widely used. the

The utility model applies a new prestress mode, which is to store the prestress energy in a composite structure to prestore stress tendons. When the tendon is used, as long as the self-anchoring of the tendon is released, the target body (structure or component) can be prestressed, and there is no need for mechanical tension equipment and components to be present at the same time, so it is very convenient to apply prestress to the target body . The tensile material in the prestressed tendon is made of high-strength material, even a low-modulus high-strength organic material, and the compression material is made of high-strength and high-modulus material. The size of the prestress applied to the target body can be determined according to the deformation energy stored in the pre-stored stress tendons of the composite structure and according to the number of the stress tendons added to the target body. The size of the prestress can also be applied according to the stress distribution of the structure. The utility model can be distributed to each part of the target body, so they can change the deformation energy into a small amount and distribute it to the target body that needs prestressing, such as concrete or ceramics. The stored deformation energy is transferred and released to the structure and components in an indirect way outside the body to form prestress. The traditional prestressing technology is cumbersome in terms of two-way, three-way and multi-way prestressing, but the utility model is easier to apply two-way, three-way and multi-way prestress to structures and components, eliminating the need for pre-holed pipes and Anchors, eliminating the inconvenience of large-scale equipment required for prestressing. The stress applied by it is evenly or gradiently distributed in the required parts of the components and structures, and it is easy to implement concrete structures with high crack resistance, water resistance, durability and corrosion resistance in large areas, so it can Implementations that are difficult to implement in existing technologies. the

The utility model is widely used in hydraulic structures such as ports, wharves and dams, protective structures of supports and retaining walls, road projects on subgrade roads, track slab facilities of high-speed railways, waterproof structure projects of underground buildings, marine and offshore projects, and large-span frames. beams and columns. The utility model can also be applied to high-strength and high-performance ceramics to improve its tensile strength and toughness. It is suitable for fiber reinforcement of components requiring high strength, high stiffness, high temperature resistance and high temperature thermal shock resistance, such as aerospace vehicles, nuclear reactor walls, and combustion turbine burners. It is suitable for gun barrels, armored vehicles, spacecraft, internal combustion engine cylinders, and brake equipment. It is used for fiber reinforcement in structures that require high strength, high stiffness, high temperature resistance and impact resistance. the

In order to achieve the above object, the technical solution adopted in the utility model is:

A pre-stored stress tendon in a composite structure, which includes an outer tube with at least one hole and at least one core, and its structural features are: the core is placed in the hole of the outer tube, and one of the outer tube and the core One is a tension body, and the other is a compression body. The outer tube and the core body are anchored and connected by one of the bonded anchoring method and the composite bonded anchoring method to form a tension-compression balance body. the

A heating element for controlling the bonding and anchoring strength of the adhesive in the tension-compression balance body is provided in the tension-compression balance body through temperature rise. Raise the temperature of the anchoring area in the tension-compression balance body by heating the heating element or directly, so that at least one of the adhesive and the core body loses its load-bearing capacity, and the bonding and anchoring are released, causing the outer tube to retract or elongate. The body is prestressed. the

The outer tube and the core are directly bonded and anchored to form a tension-compression balance body. A heating element is arranged in the tension-compression balance body, and the thermal change temperature of the core material is lower than the limit service temperature of the outer tube. the

There is a gap between the outer tube and the core body or an expansion gap at the end of the core body, and an adhesive is provided in the gap or the expansion gap. the

The outer tube and the core body are anchored by an adhesive pin anchorage to form a tension-compression balance body, and the pins in the adhesive pin anchorage are bonded at the end of the outer tube. the

The outer tube and the core are anchored by an adhesive cap tube anchor or an adhesive sleeve anchor to form a tension-compression balance body, and the cap tube or the adhesive sleeve anchor in the adhesive cap tube anchor The sleeve in the core is bonded to the end of the core. the

The outer tube is formed by splicing at least one segment through an adhesive, and the number of radial segment layers of the outer tube is one layer or multiple layers. the

The heating element is at least one of metal material, conductive carbonaceous material and ferromagnetic material. the

The heating element is an outer tube or a core. the

The heating element is electrically connected with the wire. the

For the convenience of description, the utility model temporarily refers to the pre-existing stress tendons of the composite structure as pre-existing stress tendons. According to the different direction of force exerted by the tendon on the target body, it can be divided into two types: the tendon with pre-compression function for applying compressive stress to the target body and the tendon with pre-tension function for applying tensile stress to the target body. the

(1) Prestored stress tendons with preloading function

According to the structural composition and anchoring method of this kind of tendon, it can be divided into five categories: the first category is composed of the outer tube and the core through the interface of the two. Tensile body, the core body is a compression body; the second type is composed of an outer tube and a core body bonded and anchored by an adhesive, which is a full-interface bonded anchor, in which the outer tube is a tension body and the core body is a compression body The third type is composed of the outer tube and the core body anchored by one of the bonded anchors and bonded-mechanical clamping anchors, which is the end bonded anchor, wherein the outer tube is the tension body , the core is a compression body; the fourth type is composed of an outer tube and an inner tube bonded and anchored by an interface adhesive, which is a full-interface bonded anchor, in which the outer tube is a tension body and the inner tube is a compression body; The fifth type is composed of the outer pipe and the inner pipe anchored by one of the bonded anchors and bonded-mechanical clamping anchors. It is end-bonded anchorage, in which the outer pipe is the tension body. The inner tube is a pressure body. the

The bonded anchoring method refers to an anchoring method in which in the tension-compression balance body, the joint surface of the components is to transmit the anchoring force through bonding. The composite bonded anchoring method refers to an anchoring method in which in the tension-compression balance body, the joint surface of the components is combined with bonding and mechanical clamping to transmit the anchoring force. the

The bonded anchoring method facilitates the manufacture of pre-stored stress tendons with smaller cross-sectional sizes. The composite bonding anchoring method increases the stability and flexibility of component anchoring, and facilitates the manufacture of tendons and the release of prestress. the

There are two ways to release the prestress of the pre-stored stress tendons: 1. If the anchoring method of the tensile body and the compression body of the tendon is end anchoring, and the anchoring area of the end is exposed outside the target body. According to different anchoring methods, the prestress release method can release the prestress by raising the temperature of the anchorage area, or directly cut off the anchorage area to release the anchorage, or loosen the mechanical anchorage to release the anchorage, and apply prestress to the target body. 2. If the anchoring method of the tensile body and the compression body of the tendon is bonded anchoring, and the anchoring area is in the target body. By increasing the temperature of the anchoring adhesive, the anchorage will fail, and the tensile pressure of the tension body and the compression body will be out of balance, causing the outer layer of the tendon to shrink or elongate to apply prestress to the target body. the

The utility model is a measure for releasing the prestress by increasing the temperature of the prestored stress tendons. The principle is that the increase in temperature cannot affect the performance of the base material, and the principle is that the outer tube can work normally at the temperature when the stress is released. When the pre-stored stress tendons anchorage areas are all in the target body, the methods for raising the temperature of the materials in the pre-stored stress tendons include: 1. Set up a heating body in the pre-stored stress tendons and use it to heat up. If electromagnetic induction heating is used, a ferromagnetic body is introduced into the core, outer tube or binder as a heating element. If electric current heating is used, the conductor laid in the anchoring area of the pre-existing stress tendon is used as the heating element. 2. There is no heating body in the pre-existing stress tendons, and the pre-existing stress tendons are directly heated by heat conduction to make the bonding and anchoring invalid and release the prestress; this method is mainly for bonding and anchoring at the end of the exposed target body. the

In the tension-compression balance body, a heating body is set up according to the energy input characteristics of the current heating and electromagnetic induction heating methods, so as to increase the temperature to control the bonding and anchoring strength in the tension-compression balance body and release the pre-stored stress tendons of prestress. According to the energy input characteristics of these two heating methods, the heating element is set up as follows:

1. Electromagnetic induction heating. the

Electromagnetic induction heating is to use the alternating magnetic field generated by the coil to pass through the substrate to heat the pre-stored stress tendons with ferromagnetic metal materials, so that the pre-stress of the pre-stored stress tendons is released. The following describes how to set up the heating elements of various types of tendons:

The first type of pre-existing stress tendons. When the outer tube is made of non-ferromagnetic material, there are three ways to set up the heating element: 1. Coating, winding or braiding ferromagnetic metal material on the surface of the outer tube as a heating element; 2. Coating ferromagnetic metal material on the surface of the core as a heating element. Heating body; 3. Directly insert ferromagnetic metal material powder into the core as a heating body. When the outer tube is made of ferromagnetic material, it is directly used as a heating element. the

The second type of pre-existing stress tendons. When the outer tube is made of non-ferromagnetic material, there are three ways to set up the heating element for heating the binder: 1. Coating, winding or braiding ferromagnetic metal material on the surface of the outer tube as the heating element; 2. If the core is iron The magnetic metal material is used as a heating element, otherwise, the ferromagnetic metal material is coated, wound or woven on the surface of the core as a heating element. 3. Fill the ferromagnetic metal material powder directly in the binder as a heating element. the

The third type of pre-existing stress tendons. When the ends of the tendons are anchored with adhesive, the adhesive is heated in the anchoring area, and the location of the heating element is set up in the same way as the second type of pre-stored stress tendons. the

The fourth type of pre-existing stress tendons. When the outer tube is made of non-ferromagnetic material, there are three ways to set up the heating element for heating the binder: 1. Coating, winding or braiding ferromagnetic metal material on the surface of the outer tube as the heating element; 2. If the inner tube is made of iron If the magnetic metal material is used as a heating element, otherwise, the surface of the inner tube is coated, wound or braided with a ferromagnetic metal material as a heating element; 3. The ferromagnetic metal material powder is directly filled in the binder as a heating element. When the outer tube is made of ferromagnetic material, it is directly used as a heating element. the

The fifth type of pre-existing stress tendons. When the ends of the tendons are anchored with adhesive, the adhesive is heated in the anchoring area, and the heating element is set up in the same way as the fourth type of pre-stored stress tendons. the

This heating method is very suitable for pre-stored stress short fiber bars, and can be used for pre-stressed fiber reinforcement of concrete. the

2. Electric current heating. the

Current-through heating releases bonding and anchoring, and its heating element is arranged in the tension-compression balance body: the conductive core, the outer tube, and the adhesive are used as the heating element; winding, weaving, parallel arrangement, etc. The conductive heating wire pasted on the surface of the core or the outer tube is used as the heating element; the conductive coating sprayed on the surface of the core or the outer tube is used as the heating element. At the end of the pre-stored stress tendon, the conductive wire is connected to the heating element to form a path, and the heating element is heated by turning on the power supply. This method of heating can be used on continuous long-fiber prestressed tendons and long prestressed tendons. Its characteristic is to heat the entire prestressed tendons at the same time, so the prestress will be released at the same time. the

When designing the heating body in the pre-existing stress tendons, as long as the current is passed through the conductor, it can generate heat, so it is necessary to consider the insulation between the core, the outer tube and the interface adhesive, and also consider the temperature effect on the base material and the outer surface. If the impact of the pipe work performance is affected, the design is carried out based on the principle of minimizing the impact. The specific establishment method is as follows:

The first type of pre-existing stress tendons. When the outer tube is not a conductor or the surface of the outer tube has been coated with an insulating layer, there are two ways to set up the heating element: 1. Winding, braiding or parallel arrangement on the surface of the outer tube or the core to paste the conductive heating wire as the heating element; 2. The surface of the outer tube is coated with conductive material; 2. For the outer tube using FRP, some fibers of the outer tube can be replaced with conductive heating wires; 3. A continuous conductive heating wire is arranged in the core as a heating element. When the outer tube is a conductor, it can be directly used as a heating element or the surface fiber of the outer tube wall can be replaced with an insulated conductive heating wire. the

The second type of pre-existing stress tendons. The heating element is set up on the outer tube, and the setting methods are as follows: 1. If the outer tube contains a conductor and the inner diameter is not greater than 8mm, it can be directly used as a heating element; 2. Winding a conductive heating wire on the surface of the outer tube as a heating element; 3. If the outer tube is an FRP tube, a conductive heating wire can be laid on the surface fiber of the outer tube wall. The heating element is set up on the core, and the setting methods are as follows: 1. If the core is a conductor and the diameter is not greater than 5mm, it can be directly used as the heating element; 2. If the rib uses FRP core, the surface layer of the core can be The fiber is replaced with a conductive heating wire as a heating element; 3. If the core does not contain a conductor, coat the outer wall with a conductive material, or weave an insulated conductive heating wire on the surface of the core, or glue the insulated and conductive heating wires arranged vertically On the surface of the core, or wound resistance wire on the core as a heating element. The heating element is set up on the adhesive, and the setting method is to fill the adhesive with conductive material as the heating element. the

The third type of pre-existing stress tendons. When the end of the tendon is anchored with adhesive, the adhesive is heated in the anchorage area, and the heating element is set up in the following ways: 1. Wrap a conductive heating wire on the surface of the pin; 2. Coat the surface of the pin with conductive 3. The conductive wire implanted in the pin is used as the heating element; 3. The conductor is arranged in the adhesive in the anchoring area. the

The fourth type of pre-existing stress tendons. Heat the adhesive. The heating element is set up on the outer tube, and the setting methods are as follows: 1. If the outer tube contains a conductor and the inner diameter is not greater than 5mm, it can be directly used as a heating element; 2. If the outer tube is an FRP tube, the outer tube wall can be Some of the fibers are replaced with conductive heating wires. The heating element is set up on the inner tube, and the setting methods are as follows: 1. If the inner tube is a conductor and the outer diameter is not greater than 5mm, it can be directly used as a heating element; 2. If the rib uses FRP inner tube, the inner tube can be The surface fiber is replaced with a conductive heating wire as a heating element; 3. If the inner tube does not contain a conductor, coat the outer surface with a conductive material, or weave an insulated conductive heating wire on the outer surface of the inner tube, or make the longitudinally arranged insulating conductive heating wire The wire is glued to the outer surface of the inner tube, or the resistance wire is wound on the inner tube as a heating element. The heating element is set up in the adhesive, and the setting method is that the conductive material is filled in the adhesive as the heating element. the

The setting up of the fifth type of pre-stored stress tendon heating element is the same as that of the third type. the

In the design of the above-mentioned various tendon heating elements, a heating element is included in the pre-existing stress tendon structure, which can control the stress release of the prestressing tendons. The conductive materials of the heating body include metal wires such as iron wires and copper wires and carbon fibers. the

When selecting the heating element in the above two heating methods, the volume ratio of the heating element in the pre-stored stress tendons should be reduced as much as possible to reduce the adverse effects on other components. Special attention should be paid to the thermal expansion of pre-stored stress tendons due to temperature rise. If the temperature rise of pre-stored stress tendons is too high, excessive compressive stress will be caused to the base material, resulting in cracking and damage of the base material. Therefore, the selection of the heating element should be as far as possible aimed at the surface of the core body or the adhesive in contact with the outer tube wall, so as to reduce the calorific value, reduce the temperature rise of the pre-stored stress tendons as much as possible, and make the pre-stored stress tendons useful. Therefore, the heating element is concentrated as much as possible between the inner surface layer of the outer tube wall and the outer layer of the core body, or in the binder. the

As the outer tube composed of pre-stored stress tendons, different materials use different manufacturing methods, and the establishment of the heating element is effectively combined with the above-mentioned heating methods. The following describes the composition types of the outer tube:

1. When the outer pipe is made of homogeneous metal materials, such as carbon steel, alloy steel, etc., it is made into high-strength thin steel pipe through manufacturing technology. It is also possible to pultrude high-strength steel wires into tubes by splicing, and then pultrude them into outer tubes on a mandrel that can be removed from the mold or directly use the core or inner tube as a mandrel. Agent bonding, and the spliced steel wire can also be twisted and spirally spliced into an outer tube. The joint agent can use polyamide resin, polyethylene resin, epoxy resin, phenolic resin and other resins as the joint agent. the

2. When the outer tube is made of FRP material, with concrete as the target body, the reinforcing fiber of the outer tube can be selected from inorganic reinforcing fibers such as glass fiber, carbon fiber, ceramic fiber (SiC, Si3N4, B, Al2O3), basalt fiber, asbestos fiber, etc. At least one of them, wherein the molding medium material is selected from high-molecular polymers such as high-performance epoxy resin and high-performance phenolic resin. As for the fiber-reinforced organic fiber used for the outer tube, any organic fiber that can work normally at the temperature when the prestressed tendons are released can be used. The reinforcing fiber of the outer tube can be selected from at least one of organic reinforcing fibers such as aramid fiber and polyvinyl alcohol fiber, and the molding medium material can be selected from polyamide resin, epoxy resin, phenolic resin and other resins as the medium. The two types of reinforcing fibers can be laid on the mandrel in a straight bundle, braided or twisted spiral, soaked in the medium, extruded and solidified into a tube. Various media fillers can use calcium carbonate, kaolin, alumina trihydrate, quartz powder and other fine particles. This type of tube can also be assembled into an FRP outer tube by pultruding the formed segments on a detachable mandrel or directly using the core as a mandrel, and the joints are bonded with a high-temperature-resistant adhesive . When assembling the outer tube, the segments can also be helically twisted on the mandrel to form the outer tube. the

3. When the outer tube is made of FRP material, the prestressed tendon with ceramics as the target body is not suitable for working in ceramics due to its high molding temperature and the low working limit temperature of organic fibers, so the outer tube can be used At least one of carbon fiber, metal fiber, ceramic fiber (SiC, Si3N4, B, Al2O3), asbestos fiber, basalt fiber and other inorganic fibers, and the forming medium material is polyvinyl alcohol, polycarbonylsilane, phenolic resin, silicon carbide, oxide At least one dielectric material such as aluminum. The reinforcing fiber can be laid on the mandrel in a straight bundle, braided or twisted spiral, soaked in the medium, extruded and pultruded, and cured at high temperature after demoulding to form a tube. the

As the core body composed of pre-stored stress tendon structure, different materials use different manufacturing methods, and the establishment of the heating element is effectively combined with the above-mentioned heating methods. The following describes the composition types of the core:

1. When the core body is made of homogeneous metal material, high-strength steel wire can be used. the

2. The core body is made of particle or fiber reinforced resin-based composite material or active powder concrete material. With concrete as the target body, the particles can be calcium carbonate, kaolin, alumina trihydrate, quartz powder, steel powder and other particles. the

3. When the core body is made of FRP material, with concrete as the target body, the reinforcing fiber of the core body can be selected from inorganic reinforcing fibers such as glass fiber, carbon fiber, ceramic fiber (SiC, Si3N4, B, Al2O3), basalt fiber, asbestos fiber, etc. At least one of them, wherein the molding medium material is selected from high molecular polymers such as polyamide resin, polyethylene resin, and epoxy resin. The reinforcing fiber of the core can be selected from at least one of organic reinforcing fibers such as aramid fiber, polyethylene fiber, polyvinyl alcohol fiber, etc., wherein the molding medium material can be selected from polyamide resin, polyethylene resin, epoxy resin and other resins as the medium. Because the pre-stored stress tendons are tendons with pre-compression function, the core reinforcement fibers need to be laid into straight bundles, soaked in the medium, extruded and solidified into rods. Various media fillers can use calcium carbonate, kaolin, alumina trihydrate, quartz powder and other fine particles. the

4. When the core body is made of FRP material, ceramics are used as the target prestressed tendons, and the core body can be selected from inorganic fibers such as carbon fiber, metal fiber, ceramic fiber (SiC, Si3N4, B, Al2O3), asbestos fiber, and basalt fiber. At least one of the molding medium materials is selected from at least one medium material such as polyvinyl alcohol, polycarbonyl silane, phenolic resin, silicon carbide, and aluminum oxide. The core body is compressed in the pre-existing stress tendons, and the reinforcing fibers in the core body need to be laid into straight bundles, soaked in the medium, extruded and pultruded, and solidified at high temperature into rods after demoulding. the

As an inner tube composed of pre-stored stress tendons, different materials use different manufacturing methods, and the establishment of the heating element is effectively combined with the above-mentioned heating methods. The following describes the composition of the inner tube types:

1. When the inner tube is made of homogeneous metal material, it is the same as the outer tube manufacturing method, but when the steel wires are spliced together, the straight bundle type is used to splice the tubes, because the inner tubes are under pressure here. The joint agent can use epoxy resin, phenolic resin and other resins as the joint agent. the

2. When the inner pipe is made of FRP material, concrete is used as the target object, and the method is the same as that of the outer pipe, but the reinforcing fibers can be laid in straight bundles on the mandrel. When splicing, it should also be spliced into an inner tube in a straight bundle. the

3. When the inner tube is made of FRP material, ceramics are used as the target prestressed ribs, and the method is the same as that of the outer tube, but the reinforcing fibers can be laid in straight bundles on the mandrel. the

The outer tubes of various materials described above are effectively combined with the core body to form pre-stored stress tendons under the condition that the heat-changing temperature can work normally. the

Adhesive for the anchoring of the outer tube and the core or the inner tube. When concrete is used as the target, the adhesive can be polymer thermosetting resin or thermoplastic resin, and its heat change temperature is between 40°C and 300°C. The working temperature should be above 25°C. Such as unsaturated polyester, epoxy resin, polystyrene, polymethyl methacrylate, phenolic resin and their modified products. Inorganic binders and metal binders can also be used for anchoring the ends. When ceramics are used as the target body, inorganic binders and metal binders can be used as binders. Such as phosphate inorganic adhesives. the

The shape of pre-existing stress tendons can be plates, blocks, tubes, columns, special-shaped, hollow, and honeycomb shapes of any geometric shape. Section type can be polygonal, circular, circular, elliptical, special-shaped. Its size can be made into larger-sized rods and plates, and can be made into smaller-sized fibers. The surface of the outer tube, core body and inner tube can be specially treated to be uneven, which can improve the bonding force, friction force and mechanical bite force of each layer of the interface. the

The structural fabrication and stress release methods of the five types of pre-existing stress tendons are described below. Give the setting first: the suitable temperature refers to the temperature at which the target body, the outer tube, the core and the adhesive can work normally; the thermal change temperature refers to the strength of the adhesive or the core when the temperature rises to a certain value Loss, the anchoring failure of the pre-stored stress tendon body, the temperature when its prestress is released. For example, the temperature of the binder or the core reaches the heat distortion temperature, glass transition temperature or melting temperature. the

The manufacturing method of the pre-existing stress tendons for the first type of structure: inject the uncured fluid core material into the outer tube; or penetrate the formed core into the outer tube, and heat and soften the core. Before the core body is cured, the outer tube is stretched, and after it reaches the designed tensile stress value, the core body is cured, and the core body reaches strength, and the interface between the two also reaches shear strength. When the stretched outer tube is loosened, the outer tube will retract, and the core body will shrink under compression. After balancing, the pre-existing stress tendon stress structure is completed. the

Prestress release of pre-stored stress tendons: Distribute the manufactured pre-stored stress tendons into the target body. After the component reaches the design strength, use the sensitivity of the core body strength to temperature to increase the temperature of the core body through the established heating body. When it reaches the thermal temperature at which it loses its strength, the core cannot bear the force, and the outer tube retracts. Therefore, the core can only bear the pressure through the base material combined with the outer surface of the outer tube, that is, to apply precompressive stress to the target body. the

The manufacturing method of pre-existing stress tendons for the second type of structure: at a suitable temperature, dip the core body with a liquid binder, fill the outer tube with a liquid binder, or directly inject the binder into the core The gap between the body and the outer tube, and then the core body is inserted into the outer tube. The outer tube is stretched before the adhesive is cured, and the adhesive is cured after the outer tube reaches the designed tensile stress value. When the stretched outer tube is released, the outer tube retracts and the core shrinks under compression. After balancing, the pre-existing stress tendon stress structure is completed. In this manufacturing method, the core body that penetrates the outer tube can be compressed in advance, and after the outer tube and the core body reach the designed tensile stress and compressive stress values respectively, the adhesive is cured, and then the outer tube and the core body are loosened to complete the pre-preservation process. Manufacture of stressed tendon structures. the

If the adhesive adopts cold gel, its manufacturing method is as described above, except that the adhesive is in a thermally variable temperature environment, and the adhesive is in a fluid state. Then carry out the above process, and after the outer tube is stretched to the design, the binder is cooled to a suitable temperature to recover the strength, and the pre-stored stress tendons are made. If the compression core process is adopted, the method is the same as above. the

The pre-stored stress tendons can also be manufactured by splicing, and its manufacturing method is the same as the splicing method in the embodiment. the

Prestress release of pre-stored stress tendons: Distribute the manufactured pre-stored stress tendons into the target body that needs prestress. After the component reaches the design strength, use the heating body set up to heat up the adhesive. In the process of heating and heating, the adhesive force gradually decreases with the decrease of the strength of the adhesive, the outer tube and the core body slowly produce relative slippage, the outer tube retracts, the core body elongates, and the base material passes through the outer tube and the core body. The interfacial cohesion shrinks under compression. During this process, the tension-compression balance body composed of the outer tube and the core gradually transforms into a balance body composed of the outer tube and the base material. When the adhesive basically loses its cohesive force, that is, when the heat transition temperature is reached, the sliding between the outer tube and the core tends to be stable. The outer tube and the base material form a new tension-compression balance body to complete the release of prestress. This process also means that the base material gradually accepts the pressure transferred by the core body and becomes a compression body, while the outer tube is still a tension body. the

Pre-existing stress tendons for the third type of structure. The methods of anchoring the end of the prestressed tendon include: 1. bonded anchoring at the end; 2. extrusion friction mechanical anchoring at the end; the

The manufacturing method of the pre-existing stress tendon is as follows: Method 1. Insert the core body into the outer tube, inject a certain amount of adhesive into the gap between the outer tube and the end of the core body, stretch the outer tube to reach the preset stress value, and keep the stress value. After the adhesive is cured, the tension of the outer tube is loosened to complete the manufacture. Method 2: Put the core body into the outer tube, inject a certain amount of adhesive into the gap between the outer tube and the end of the core body, stretch the outer tube, compress the core body to reach the preset stress value, and maintain the stress value. After the adhesive is cured, the outer tube and core are loosened to complete the manufacture. Method 3: Insert the core body into the outer tube, stretch the outer tube to reach the preset stress value, and maintain the stress value. A pin soaked with adhesive is inserted into the end of the outer tube, and after the adhesive is cured, the tension of the outer tube is released to complete the manufacture. Method 4: Insert the core body into the outer tube, stretch the outer tube, and compress the core body. After the two reach the preset stress value and maintain the stress value, insert a pin soaked in adhesive at the end of the outer tube. After the adhesive is cured, the outer tube and the core are loosened to complete the structural fabrication. Method 5: Process the opening of the outer tube into a nut in advance, insert the core into the outer tube, stretch the outer tube to reach the preset stress value, and maintain the stress value. After the screw rod is used as a pin to screw into the outer tube port to anchor the core, the tension of the outer tube is loosened to complete its structural manufacture. the

Release of the prestress of the pre-stored stress tendon: If the end of the pre-stored stress tendon is in the target body, after the component reaches the design strength, the heating element is used to raise the temperature of the adhesive, so that the adhesive reaches the thermal change temperature, and the pre-stress is released to the target. If the end of the pre-stored stress tendon is outside the target body, after the component reaches the design strength, the anchorage end is cut off by mechanical cutting to release the prestress, or the anchorage area of the end is heated and softened to release the prestress. the

For the pre-existing stress tendons composed of the fourth type of structure. This type of pre-existing stress tendon uses a temporary anchor core as the tension tendon to pre-press the inner tube to reduce the elastic retraction of the outer tube. Its manufacturing method is as follows:

Firstly, the inner tube is preloaded with the ribs. The anchoring method of the tensioned tendon is anchored by end adhesive. Stretch the tendons that have penetrated into the inner tube to reach the preset stress value, and then anchor the two ends of the ribs to the two ends of the inner tube to complete the preloading of the inner tube. For pre-pressing the inner tube first and then penetrating in the outer tube, or first penetrating in the outer tube and then pre-pressing the inner tube. The sequence does not affect the effect of the ribs on the preloading of the inner tube. the

The manufacturing method of this type of pre-existing stress tendons: at a suitable temperature, dip the outer surface of the inner tube with strong ribs into a liquid adhesive, inject the liquid adhesive into the outer tube, and then place the inner tube with strong ribs Penetrate into the outer tube; or directly inject the adhesive into the gap between the inner tube and the outer tube. Tension tendons are first stretched, and after the stress value is reached, both ends of the inner tube are anchored to complete the preloading of the inner tube, and then the outer tube is stretched. After the outer tube reaches the designed tensile stress value, the adhesive between the inner tube and the outer tube is cured. Then loosen the stretched outer tube, release the anchorage between the tendons and the inner tube, pull out the tendons from the inner tube, and complete the manufacture of the stress-bearing structure of the pre-stored stress tendons. the

If the bonding agent adopts cold gel, its manufacturing method is the same as the manufacturing method of the above-mentioned pre-stored stress tendons, but its manufacturing environment temperature is the temperature when the bonding agent is in a fluid state, but when the ambient temperature is cooled to a suitable temperature, the bonding agent will Curing and anchoring the outer tube and the inner tube, other procedures are the same as above. the

The prestress release of this type of pre-stored stress tendons is the same as the pre-stress release of the second type of pre-stored stress tendons. the

For the pre-existing stress tendons composed of the fifth type of structure, the preloading of the inner tube and its manufacturing method are as described in the fourth type of tendons, only the gap between the ends of the outer tube and the inner tube is filled with adhesive, and the outer tube and the inner tube For anchoring, other methods are similar to those of the fourth type of reinforcement. the

The above five types of pre-stored stress tendons, after the pre-stress is released, the heating body will no longer generate heat. When the pre-stored stress tendons cool to a suitable temperature, the anchorage between the core material and the outer tube will recover, and the core material will participate in tension together with the outer tube, so that it will not cause waste of material. If it needs to be twisted into a pre-existing stress tendon stranded wire, its diameter should be controlled within the range of 10mm. The setting of the heating element adopts any setting method in the above-mentioned heating method. the

(2) Pre-existing stress tendons with pre-tensioning function

According to the structural composition and anchoring method of this kind of tendon, it can be divided into four categories: the first category is composed of the outer tube and the core body through the interface of the two. , the core body is a tension body; the second type is composed of an outer tube and a core body bonded and anchored by an adhesive, which is full-interface anchoring, in which the outer tube is a compression body and the core body is a tension body; the third type It is composed of the outer tube and the core body through the end bonding anchoring or mechanical anchoring, which is part of the interface anchoring, in which the outer tube is the compression body and the core body is the tension body; the fourth type is the outer tube and the inner tube through the interface. The adhesive bonded anchoring structure is full-interface anchoring, in which the outer tube is the compression body and the inner tube is the tension body. the

The following describes the pre-existing stress tendons with compressive stress function. Only the second and third types of the most effective pre-existing stress tendon structure manufacturing methods are described below:

The manufacturing method of the second kind of pre-stored stress tendons is as follows: dip-coating the core body with a liquid adhesive at a suitable temperature, filling the outer tube with the liquid adhesive, and then inserting the core body into the outer tube. Stretch the core, pre-press the outer tube, and cure the adhesive after the two reach the designed stress value. Then loosen the core body and the outer tube, cut off the excess core body, and complete the structural manufacture of the rib. the

The third type of pre-existing stress tendon manufacturing method is: method 1, the core body is penetrated into the outer tube, a certain amount of adhesive is injected into the gap between the outer tube and the end of the core body, the core body is stretched, and the outer tube is compressed to achieve the desired Set the stress value and keep the stress value. After the adhesive is cured, the outer tube and core are loosened to complete the manufacture. Method 2: Put the core body into the outer tube, put anchor tubes on both ends of the core body in advance, stretch the core body to reach the preset stress value, and maintain the stress value. Hold the anchor tube against and pre-press the outer tube, apply or inject adhesive into the gap between the anchor tube and the core, solidify the adhesive to form an end anchor, loosen the outer tube and core, and cut off the excess core. Complete its structural fabrication. the

If the two types of pre-stored stress tendons mentioned above need to be twisted into pre-stored stress tendon stranded wires, their diameters should be controlled within the range of 10mm. The setting of the heating element adopts any setting method in the above-mentioned heating method. the

The anchoring methods of various pre-existing stress tendons mentioned above can be combined with each other to enhance the anchoring performance. the

Compared with the prior art, the beneficial effect of the utility model is: when the utility model is laid in the target body (structure or component), the temperature of the adhesive is raised through the heating element, and when the thermal change temperature is reached, the adhesive The agent loses its strength and loses its cohesive force, breaking the original tension-compression balance, causing the outer tube to shrink or elongate, and applying pre-compression stress or pre-tension stress to the target body through the bonding force between the outer tube and the target body base material, so that the outer tube A new tension-compression balance body is formed with the target body, that is, the prestress stored in the pre-stored stress tendons of the composite structure is released into the target body. the

The utility model increases the flexibility and simplicity of the prestressed reinforcement, better improves the mechanical performance of the structure; solves the problem of low elongation of reinforcements without prestressed fibers or fiber bundles, and increases the strength of brittle materials. toughness. It solves the problem that the previous prestressing technology is difficult to implement in multi-directional prestressing and large-area body prestressing, and improves the ability of prestressing technology to be widely used. It is mainly suitable for target bodies with bonding and internal prestressing. , and its application objects are brittle materials such as concrete and ceramics. the

Below in conjunction with accompanying drawing and embodiment the utility model is described further. the

Description of drawings

In the following figures 7 to 28, since there are many ways to set up the heating element, the layout of the heating element is not shown in the figure, but only the stressed structure of the pre-existing stress tendons is shown. Figures 38 to 51 show relatively complete pre-existing stress tendons. the

Fig. 1 is the central axial sectional view of prestored stress tendon outer pipe;

Fig. 2 is the radial sectional view of prestored stress tendon outer pipe;

Fig. 3 is the central axial sectional view of the pre-stored stress tendon core;

Fig. 4 is the radial sectional view of prestored stress tendon core body;

Figure 5 is a central axial sectional view of the pre-stored stress tendon inner pipe;

Fig. 6 is the radial sectional view of prestored stress tendon inner pipe;

Fig. 7 is a central axial sectional view of the first type of pre-existing stress tendon stress structure with preloading function;

Fig. 8 is a radial cross-sectional view of the first type of pre-stored stress tendon stress structure with preloading function;

Fig. 9 is a sectional view of the stressed structure of the second type of pre-stored stress tendon with preloading function;

Fig. 10 is the radial sectional view of Fig. 9;

Figure 11 is a sectional view of the third type of pre-stored stress tendons with pre-loading function;

Fig. 12 is the radial sectional view of Fig. 11;

Figure 13 is a cross-sectional view of the fourth type of pre-existing stress tendons with pre-compression function

Fig. 14 is the radial sectional view of Fig. 13;

Figure 15 is a cross-sectional view of the fifth type of pre-existing stress tendons with pre-compression function

Figure 16 is a radial sectional view of Figure 15;

Figure 17 is a cross-sectional view of a stress-bearing structure of the fifth type of pre-existing stress tendons with pre-compression function

Fig. 18 is the radial sectional view of Fig. 17;

Figure 19 is another cross-sectional view of the fifth type of pre-existing stress tendons with pre-compression function

Figure 20 is a radial sectional view of Figure 19;

Figure 21 Sectional view of the second type of pre-existing stress tendons with pre-tensioning function

Figure 22 is a radial sectional view of Figure 21;

Fig. 23 has the sectional drawing of the stress structure of the third kind of pre-existing stress tendon with pre-tensioning function,

Fig. 24 is the radial sectional view of Fig. 23;

Figure 25 is a sectional view of the second type of continuous long pre-existing stress tendon stress structure in the expansion gap,

Fig. 26 is the radial sectional view of Fig. 25;

Fig. 27 is a cross-sectional view of the stress structure of the fourth type of continuous long pre-stored stress tendon in the expansion gap,

Figure 28 is a radial sectional view of Figure 27;

Figure 29 is a cross-sectional view of the prestressed tendon formed by combining three segments of the outer tube,

Figure 30 is a cross-sectional view of the prestressed tendon formed by the assembly of six segments of the outer tube,

Figure 31 is a radial cross-sectional view of the fiber reinforced composite core

Figure 32 Radial cross-sectional view of fiber reinforced composite outer tube or inner tube

Fig. 33 is the schematic diagram of the manufacturing method of fiber bundle tube and fiber bundle core;

Fig. 34 is the schematic diagram of the prestressed tendon manufacturing method of each section stress value controllable storage;

Fig. 35 is the schematic diagram of the prestressed tendon manufacturing method that two pieces of segments are assembled into pipe;

Figure 36 is a schematic diagram of the manufacturing process of the second type of pre-stored stress tendons;

Figure 37 is a schematic diagram of the manufacturing process of the fourth type of pre-stored stress tendons;

Figure 38 is a cross-sectional view of the pre-existing stress tendon anchored by the adhesive pin anchorage and reserved expansion space,

Figure 39 is a radial sectional view of Figure 38;

Figure 40 is a cross-sectional view of the pre-stored stress tendon anchored by the adhesive pin anchorage and the end of the outer pipe bonded to the casing,

Figure 41 is a radial sectional view of Figure 40;

Figure 42 is a cross-sectional view of the pre-existing stress tendons of the adhesive anchorage and the end of the outer pipe cemented to the casing,

Figure 43 is a radial sectional view of Figure 42;

Figure 44 is a cross-sectional view of the second type of pre-stored stress tendon with pre-compression function, conductive heating wire, and expansion space reserved

Figure 45 is a radial sectional view of Figure 44;

Figure 46 is a cross-sectional view of the second type of pre-stored stress tendons with pre-loading function, conductive wires laid out, and casings cemented at the end of the outer pipe,

Figure 47 is a radial sectional view of Figure 46;

Figure 48 is a cross-sectional view of the second type of pre-stored stress tendons with pre-compression function, the core body is a heating body, and expansion gaps are reserved,

Figure 49 is a radial sectional view of Figure 48;

Figure 50 is a cross-sectional view of the second type of slender pre-stored stress tendon with preloading function, steel core body heating element and introduction of casing;

Fig. 51 is a cross-sectional view of the second type of pre-stored stress short fiber with pre-compression function, steel core heating element and foam body. In the picture

1-fiber; 2-medium; 3-outer tube; 4-core; 5-binder; 6-expandable gap;

7-inner tube; 8-hollow part of inner tube; 9-sleeve; 10-gap between outer tube and core; 11-segment;

12-joint seam; 13-pin; 14-pin opening; 15-conductive heating wire; 20-casing; 21-glue;

22-wire; 24-sealing glue; 25-foam, 26-foam matrix; 27-air hole; 28-sealing sheet;

29-extrusion forming hole; 30-curing area; 31-anchor. the

Detailed ways

As shown in Figures 1 to 6, the cross-sectional shape of the outer tube 3, the core body 4, and the inner tube 7 can also be any shape such as polygon, ellipse, and special shape, and the convex and concave shapes of the surface are not shown in the figure. The core body 4 and the inner tube 7 can be made of at least one of fiber reinforced composite material, particle reinforced resin matrix composite material, homogeneous metal material, and active powder concrete material. The outer tube 3 may be made of at least one of fiber reinforced composite material and homogeneous metal material. In order to enhance the bonding force between the pre-stored stress tendons and the base material, the outer surface of the outer tube can be roughened or mechanically deformed along the length direction of the stress tendons. Under the condition that the inner diameter of the outer tube is constant, the inner and outer surfaces may be smooth, indented, deformed, wavy, spiral, twisted, end-enlarged, or other anchorage shapes. The enlarged outer tube at the end is also very conducive to the stretching of the outer tube. the

As shown in Figures 7 and 8, the outer tube 3 and the core body 4 are directly anchored by the combination force of the two to form a tension-compression balance body. Wherein the outer tube 3 is under tension, and the core 4 is under compression. The function of the telescopic gap 6 is to leave an elongation space for the compressed core 4 when the prestress is released, so as not to elongate and push against the base material, hindering the release of the prestress. If the structure does not reserve the telescopic gap 6, the casing 20 (shown in Figures 38 and 39) can be placed at both ends to replace the function of the telescopic gap 6, and at the same time it can protect the terminal at the end of the tendon . If the inner diameter of the outer tube 3 is less than or equal to 5 mm, a casing 20 can be used to replace the telescopic gap 6 at one or both ends of the pre-stored stress tendons. The layout of the heating element is not shown in this figure. The release of the prestress is to release the prestress by heating the core body 4 with the arranged heating element. The inner surface of the casing 20 is threaded or deformed, and the outer surface of the end of the outer tube 3 is processed into threads, so that the casing 20 can be twisted on the end of the outer tube 3 like a nut to form a mechanical fixation; Inject adhesive to enhance fixation. the

As shown in Figures 10 and 11, the outer tube 3 and the core body 4 are bonded and anchored through the entire interface of the adhesive 5 to form a tension-compression balance body. Wherein the outer tube 3 is under tension, and the core 4 is under compression. Reserving telescopic space 6 and casing 20 situation are consistent with above-mentioned. The layout of the heating element is not shown in this figure. The release of the prestress is to release the prestress by heating the adhesive 5 with the arranged heating element. the

As shown in Figures 11 to 14, in Figures 11 and 12, the ends of the outer tube 3 and the core 4 are bonded and anchored by the adhesive 5 to form a tension-compression balance body. Reserving telescopic space 6 and casing 20 situation are consistent with above-mentioned. If the anchoring area is exposed in the target body, the way to release the anchorage at the end and release the prestress is to use a heating element to heat up the anchoring area. If the anchoring area is exposed outside the target body, the way to release the anchorage of the end is to heat up the anchoring area or cut it mechanically. In Figures 13 and 14, the outer tube 3 and the pin 13 are bonded at the end by the adhesive 5, and the pin 13 bears the extrusion force of the core 4, so that the outer tube 3 and the core 4 form a tension-compression balance body , can apply precompressive stress to the target body. The effect of the pin opening 14 is to prevent the adhesive from being extruded, and to bleed out the volume gas occupied by the pin 13 in advance, because in the manufacturing process, when the pin 13 coated with the adhesive 5 is inserted into the outer tube 3, Adhesive 5 is flow state, is easy to be extruded, so perforate in pin 13. But if the pin diameter is very small, there is no need to open the vent hole. The layout of the heating element on the pin 13 is not shown in this figure. Reserving telescopic space 6 and casing 20 situation are consistent with above-mentioned. If the anchoring area is exposed in the target body, the way to release the anchorage at the end and release the prestress is to use a heating element to heat up the anchoring area. If the anchoring area is exposed outside the target body, the way to release the anchorage of the end is to heat up the anchoring area or cut it mechanically. the

As shown in Figures 15 and 16, the outer tube 3 and the inner tube 7 of the structural tendons are bonded and anchored through the entire interface of the adhesive 5 to form a tension-compression balance body. Wherein the outer tube 3 is under tension, and the inner tube 7 is under compression. Reserving telescopic space 6 and casing 20 situation are consistent with above-mentioned. the

As shown in Figures 17 and 18, the outer tube 3 and the inner tube 7 are bonded and anchored at the ends by using the adhesive 5 to form a tension-compression balance body. Reserving telescopic space 6 and casing 20 situation are consistent with above-mentioned. The way to release the anchorage area is the same as that described in Figures 11 and 12. the

As shown in Figures 19 and 20, the outer tube 3 and the pin 13 are bonded at the end with the adhesive 5, and the pin 13 bears the extrusion force of the inner tube 7, so that the outer tube 3 and the inner tube 7 form a tension and compression balance body. Reserving telescopic space 6 and casing 20 situation are consistent with above-mentioned. The way to release the anchorage area is the same as that described in Figures 13 and 14. the

As shown in Figures 21 and 22, the outer tube 3 and the core body 4 are bonded and anchored through the entire interface of the adhesive 5 to form a tension-compression balance body. Wherein the outer tube 3 is a compression body, and the core body 4 is a tension body. If the resistance heating method is used to release the prestress, a protective sleeve 20 is used at one or both ends of the tendon to protect the wiring at the end. The release of the prestress is released by heating the heating element. the

As shown in Figures 13 and 24, the sleeve 9 is bonded and anchored to the end of the core 4 with an adhesive 5, and the outer tube 3 and the core 4 are anchored to form a tension-compression balance body. If the anchoring area is in the target body, the way to release the end anchorage and release the prestress is to use a heating element to heat up the anchoring area. If the anchoring area is exposed outside the target body, the way to release the anchorage of the end is to heat up the anchoring area or cut it mechanically. The situation that adopts casing 20 is described with Fig. 21,22. the

As shown in Figures 25 and 26, when the prestressed tendon is very long, the elongation and displacement of the core body 3 is very large. If the displacement of the core body at the end is satisfied only through the telescopic gap at both ends or the casing 20, then its Longer lengths are required. When the prestress is released, the displacement and slippage of the core body 4 is large, especially at the end of the core body 4 . Therefore, in order to reduce the displacement of the end of the core body 4, the core body 4 is divided into sections, and corresponding expansion and contraction gaps are reserved between the sections. the

As shown in Figures 27 and 28, the situation in Figures 27 and 28 is the same as in Figures 25 and 26, except that the core body in Figures 11 to 14 is replaced with an inner tube 7. the

As shown in Figures 31 and 32, the outer tube 3 or inner tube 7 is a circular section FRP (fiber reinforced composite) outer tube made of fibers and media, and the core 4 is a circular section made of fibers and media The FRP core body, the inner tube 7 is an FRP inner tube with a circular section made of fibers and media. Where 1 is a fiber made of x components and 2 is a medium made of y components. The three can be composed of unidirectionally arranged fibers and media, or composed of woven fiber nets and media. The cross-sectional size of FRP bars can be changed by adjusting the number of fibers or the content of media. the

In order to illustrate the utility model more clearly, the embodiments of the utility model are specifically described below in conjunction with the accompanying drawings. the

Example 1

As shown in FIGS. 44 and 45 , first, a method of manufacturing a CFRP (carbon fiber reinforced composite material) outer tube 3 will be described. 33 and 34 are schematic views of the manufacturing method of the fiber bundle outer tube 3 and the fiber bundle core 4 . Arrange several pitch-based continuous carbon fibers in parallel in the same direction on the mandrel, or weave and twist on the mandrel, soak in the mixed glue solution with 50% weight of phenolic resin and ethanol, and pultrude through the forming hole , heated at 300°C for 1 hour to cure the phenolic resin to make a CFRP outer tube. The medium of the CFRP outer tube can also use polyimide. The inner and outer surfaces of the CFRP outer tube can be treated to be uneven to increase its bonding force with the base material and the inner structure of the tube. During the manufacturing process of the CFRP outer tube, the inner diameter and outer diameter of the CFRP outer tube 3 are changed by changing the number of carbon fibers used, and the diameters of the mandrel and the forming hole. the

The manufacturing method of the steel core body 4 and the layout of the heating element. As shown in Figures 42 and 43, a high-strength steel wire of appropriate size (steel bundles are used if large-scale pre-stored stress tendons are required) is used as the core body 4, and a plurality of conductive heating wires 15 coated with insulating paint are braided on its surface ( carbon fiber, copper wire, etc.) mesh sleeve as a heating element, or the conductive heating wire 15 is wound on the steel core 4 as a heating element. The specific method is to soak a plurality of conductive heating wires 15 in the epoxy resin glue solution with curing agent, weave or wind them on the steel wires, and after the epoxy resin is cured, the conductive heating wires 15 are bonded to the surface of the steel wires to form a Steel core body 4 with heating element. It is also possible to paste the conductive heating wires 15 on the surface of the steel wires in the same direction in parallel to form a steel core body 4 with a heating element. the

In this embodiment, as shown in Figures 44 and 45, the pre-stored stress tendons are constructed, and the adhesive 5 is epoxy resin filled with porcelain powder and quartz powder. But the adhesive 5 can also use other types of resin adhesives. Mix epoxy resin with curing agent, accelerator and diluent with porcelain powder and quartz powder filler to form Adhesive 5 glue. Inject the glue into the outer tube 3, then soak the steel core 4 with the heating element into the adhesive 5, and penetrate into the outer tube 3. The outer tube 3 is stretched with a tensioner to make its stress reach the design value, the epoxy resin is cured, the outer tube 3 is loosened, and the structure of pre-stored stress ribs is completed. Fig. 36 is a schematic diagram of the manufacturing process of the second type of pre-existing stress tendons. The length of the telescopic gap 6 is controlled by the blanking length of the outer tube and the core body and the stress of tension, so it must be determined by calculation in advance. Then connect the conductive heating wire 15 and the lead wire 22 at the end of the force tendon, and coat the hot-melt sealing glue 24 at the openings at both ends of the outer tube to protect the lead wire 22 and prevent the base material from flowing into the telescopic space 6, and finally obtain the prestored stress tendon . There is also a kind of wiring method between the conductive heating wire 15 and the wire 22 at the end of the force tendon, which is to connect the conductive heating wire 15 at one end to each other, and the conductive heating wire 15 at the other end is divided into two groups, and two wires 22 are connected respectively. To connect the positive and negative poles of the power supply. The pre-stored stress tendons can be twisted to form stranded wires. The temperature when the prestressed tendon is released is the thermal deformation temperature of the epoxy resin. the

Adopt the pre-existing stress tendon of Fig. 46,47 structure, Fig. 46,47, the manufacturing of stress tendon of above-mentioned Fig. 44,45 structure, do not adopt casing 20. The reinforcement of this structure adopts the casing 20 to provide expansion and contraction space for the core body 4, and before the outer pipe is stretched, the iron casing 20 is glued to the end of the outer pipe 3 with the glue 21. Mix the epoxy resin with curing agent, accelerator and diluent with ceramic powder and quartz powder filler to form the adhesive 5 glue, inject the glue into the outer tube 3, and then put the steel with the heating element The outside of the core body 4 is soaked with the glue solution of the adhesive 5 and penetrates into the outer tube 3 . Stretch the outer tube 3 with a tensioner to make its stress reach the design value. After the cured epoxy resin reaches the strength value, loosen the outer tube 3, and the structure of the pre-stored stress tendons is completed. Connect the conductive heating wire 15 and the lead 22 at the end of the stress tendon, and then coat the hot-melt sealing glue 24 at the mouth of the casing 20 to complete the manufacture of the pre-stored stress tendon. Casing 20 here has the function of heading head and anchor head bearing pressure, so the adhesive 21 must have sufficient bonding strength, and its working temperature must be higher than the softening temperature of the adhesive 5, so that the casing can play its role. Therefore, the adhesive 21 of the pre-existing stress tendons of the 21B structure adopts a modified high temperature resistant epoxy resin adhesive 21 adhesive. However, if the pre-stored stress tendons of the casing 20 are used, the length of the core body can also exceed the length of the outer pipe. the

In this embodiment, if the diameter of the steel core 4 is ≤4 mm, the heating conductor is directly made of steel wire. The pre-stored stress tendons constructed in Figures 48 and 49 can be used, where 23 is a welded joint. The lead wire 22 of this tendon is to be directly welded to the two ends of steel wire, and all the other manufactures are as the manufacture method of above-mentioned Fig. 44,45 structural tendons. the

If the diameter of the steel core body 4 is less than or equal to 4mm, the heating conductor directly adopts a steel wire, and the end of the pre-stored stress tendon adopts a casing 20, as shown in FIG. 50 for the structure of the pre-stored stress tendon. The lead wire 22 of this tendon is to be directly welded or be bound at the two ends of steel wire, and all the other manufacturing methods are like the manufacture method of above-mentioned Fig. 46,47 structural tendons. the

In order to reduce the adverse effects on other components caused by the heating of the heating element, in all the embodiments where the adhesive 5 is used, the adhesive should be made as thin as possible to reduce the amount of heat diffusion and shear deformation. The pre-stored stress tendons can be twisted into stranded wires when the size is appropriate. the

Example 2

The manufacturing method of the CFRP outer tube 3 is the same as that in Embodiment 1. the

Next, a method of manufacturing the CFRP (carbon fiber reinforced composite material) core 4 will be described. As shown in Figure 33, several pitch-based continuous carbon fiber bundles arranged in the same direction are soaked in polyimide adhesive, pultruded through forming holes, and heated and cured to form a CFPR core 4. As shown in Figures 44 and 45, soak the conductive heating wire 15 coated with insulating paint in the epoxy resin glue solution with curing agent, then weave the mesh conductive heating wire 15 on the surface of the CFPR core 4 as a heating element, or The twisted conductive heating wire 15 is wound on the CFPR core as a heating element, and the epoxy resin is cured, so that the conductive heating wire 15 is bonded on the surface of the core to form a CFPR core 4 with a heating element. the

If epoxy resin is used as the medium, one method is to soak several pitch-based continuous carbon fiber bundles arranged in the same direction in epoxy resin glue, pultrude through forming holes, and cure epoxy resin to make CFPR core Body 4. Soak the conductive heating wire 15 in the epoxy resin glue solution with curing agent, weave the conductive heating wire 15 mesh cover coated with insulating paint on the surface of the CFPR core 4 as the heating element, or wind the conductive heating wire 15 on the CFPR core 4. The heating wire 15 is used as a heating element. Alternatively, the conductive heating wires 15 are pasted on the surface of the core in parallel rows to form a CFRP core 4 with a heating element. Another manufacturing method is to wind the conductive heating wire 15 in advance on the pitch-based continuous carbon fiber bundle impregnated with epoxy resin, and pultrude it through the forming hole to make the core 4 with the heating element. The surface of the core body can be treated to be uneven to increase its bonding force with the surface of the outer tube. In the manufacturing process of the CFRP core, its diameter is changed by changing the number of carbon fibers used and the diameter of the formed tube. the

The following manufacturing method is the same as that of the pre-existing stress tendons in Figure 44 and 45 and the pre-existing stress tendons in Figure 46 and 47 described in Embodiment 1, except that the steel core is replaced by a CFRP core. For the pre-existing stress tendons constructed in Figure 50, the wires 22 of the tendons are bound at both ends of the CFRP core, and the rest of the manufacturing method is the same as the manufacturing method for constructing the stress tendons in Figures 46 and 47 described in Embodiment 1. the

When the outer tube is made of high-strength steel pipe, the manufacturing method is as above, except that the high-strength steel pipe is used instead of the CFRP outer pipe 3 . the

Example 3

The manufacturing method of the high-strength steel wire spliced outer tube 3 will be described below. During the forming process of the high-strength steel wire, its wire-drawing cross-sectional shape is shown in Figure 11 in Figures 29 and 30. The outer tube 3 is formed by assembling three tube pieces 11 . The splicing connection method can use modified high-temperature-resistant epoxy resin adhesive 21 or inorganic adhesive to splice the pipes at the splicing seam 12 , or directly wind the silk thread to bundle the segments 11 into the outer pipe 3 . In the surface bonding treatment of the spliced outer tube 3, except for the seam surface, other surfaces of the steel wire can be treated with suitable spiral ribs to increase the binding force between the outer tube 3, the base material and the adhesive 5. On the division of the combined outer tube 3, the outer tube 3 can be assembled by two pieces, or by more pieces. Fig. 35 is a schematic diagram of a prestressed tendon manufacturing method in which two segments are assembled into a tube. The outer tube of the fiber reinforced composite material can also be manufactured by splicing, and the manufacturing method is as described above. After the outer tube is made, the iron casing 20 is glued to both ends of the outer tube 3 by using a modified high temperature resistant epoxy resin adhesive 21 . the

The manufacturing method of the steel core body 4 and the layout of the heating element is the same as that of the first embodiment. the

In this embodiment, as shown in Figures 44 and 45, the pre-stored stress tendons are constructed, and the adhesive 5 is epoxy resin filled with porcelain powder and quartz powder. But the adhesive 5 can also use other types of resin adhesives. Mix epoxy resin with curing agent, accelerator and diluent with porcelain powder and quartz powder filler to form Adhesive 5 glue. Inject the glue solution in the outer tube 3, then soak the steel core body 4 with the heating element into the adhesive 5 glue solution, and penetrate in the outer tube 3. Stretch the outer tube 3 with a tensioner, after the stress reaches the design value, and after the epoxy resin is cured to reach the strength, loosen the outer tube 3, and the structure of pre-stored stress ribs is completed. As shown in Figure 36, connect the conductive heating wire 15 and the lead 22 at the end, and coat the hot-melt resin sealing glue 24 at the mouth of the casing 20 to complete the manufacture of the pre-stored stress tendons. the

If the diameter of the steel core body 4 is less than or equal to 4mm, the heating conductor directly adopts the steel wire, the reinforcement adopts the casing 20, and the pre-stored stress tendon constructed in Fig. 50 can be adopted. The lead wire 22 of this tension tendon is directly welded or binds at the two ends of steel wire, and all the other manufacturing methods are like the manufacturing method of above-mentioned Fig. 44,45 structural tension tendons. the

Example 4

During the forming process of the high-strength steel wire, the steel wire is drawn into a segment 11 . The manufacturing method of the steel core body 4 and the layout of the heating element. As shown in Figures 44 and 45, soak the conductive heating wire 15 in the epoxy resin glue with curing agent, weave or wind it on the steel wire, after the epoxy resin is cured, the conductive heating wire 15 will be bonded to the surface of the steel wire On, make the steel core body 4 that has heating element. the

Adopt Figure 35 prestressed tendon manufacturing method. What is described in the above embodiments is the piercing method as the way of entering the tube, while Fig. 35 is a combined manufacturing method in which tensioning, assembling and curing are carried out simultaneously. On the left side of the figure, there are two stretched tube pieces 11 passing through the forming round hole together with the untensioned steel core 4, wherein the surface of the steel core 4 is coated with a fast-curing epoxy resin adhesive 5 , both advance at the same speed from the left side of the forming hole, pass through the forming hole for extrusion molding, reach the right side of the forming hole, and then solidify at the curing place to complete the manufacture of the pre-stored stress tendon structure. Then utilize modified high temperature resistant epoxy resin glue 21 glue 21 to glue the iron casing 20 on the two ends of the outer tube 3, connect the conductive heating wire 15 and the lead wire 22 at the end, and place it at the mouth of the casing 20 Coat the hot-melt resin sealant 24 to complete the manufacture of the pre-stored stress tendons. The size of the stored prestress value of each section of the pre-stored stress tendon manufactured by the splicing method can be controlled by the tension on both sides of the forming hole during splicing. In this way, the size of the pre-stored stress in each part of the pre-stored stress tendon can be designed and manufactured according to the stress of the target body, so as to meet the prestress value required by the corresponding part of the target body. Such as load-bearing beams, the pre-existing stress tendons are arranged in the beam body according to the anastomosis line, and according to the change of the required prestress in the tangential direction of the anastomosis line, during the pre-existing stress tendon joining process, according to the required prestress, the corresponding adjustment is made The tensile stress of the outer tube on both sides of the hole will cure the adhesive at the curing place to form pre-stored stress tendons with variable stress. the

Similarly, other types of fiber-reinforced composite material cores can be used instead of steel cores, using splicing or piercing methods, and the manufacturing method is the same as above. the

For the pre-stored stress tendons manufactured by the penetration method, if the manufacturing method shown in Figure 34 is adopted, the stored stress value of each part of the tendons can also be controlled. Fig. 34 is a schematic diagram of a prestressed tendon manufacturing method with controllable storage of stress values in each section. One end of the outer tube 3 containing the core 4 and the adhesive 5 is fixed on the anchoring seat, and the other end is anchored with an anchoring device, and tensioned. The tensile force is P longitudinal tension, the adhesive is cured by heating up, and the curing area of the adhesive moves to the direction of the tensile force. With the change of the tension P, after the adhesive in the curing area is cured, the stress stored in the outer tube 3 and the core body in tension and compression follows the change of the tension P, so the manufacturing pre-stored stress can be controlled according to the stress of the target body The size of the pre-stored stress in each part of the rib meets the prestress value required by the corresponding part of the target body. the

Example 5

The outer tube 3 of this embodiment is made of glass fiber reinforced composite material, and the manufacturing method is similar to that of Embodiment 1, and will not be repeated here. The glass fiber can also be impregnated with polyimide adhesive, pultruded through the forming hole, and then heated and cured to make the outer tube 3 by polyimide. In order to enhance the binding force between the surface of the glass fiber and the adhesive, the surface can be treated. In this embodiment, the inner diameter of the outer tube 3 is 2.5 mm, and the outer diameter is 4 mm. The diameter of the steel core is 2mm, which is directly used as a heating element. the

Adopting the structure of pre-stored stress tendons in Fig. 50, its manufacturing method: firstly, the iron casing 20 is glued to the end of the outer pipe 3 by using a modified high temperature resistant epoxy resin adhesive 21. Adhesive 5 adopts epoxy resin with porcelain powder and quartz powder as filler and polyamide resin as curing agent. Mix epoxy resin with curing agent, accelerator and diluent with ceramic powder and quartz powder filler to form adhesive 5 glue and inject it into outer tube 3, after the steel core 4 is soaked in adhesive 5 glue Penetrate in the outer tube 3. Stretch the outer tube 3 with a tensioner to make the tensile stress reach the design value, then cure the epoxy resin, loosen the outer tube 3, and the structure of the pre-stored stress tendons is completed. Connect the lead wire 22 and the steel core body 4, and then smear the hot-melt resin sealing glue 24 on the mouth of the casing 20 to complete the manufacture of the pre-stored stress tendons. It is twisted into a twisted wire, and the wires 22 of the pre-stored stress tendons at one end of the twisted wire are connected to each other, and the wire 22 at the other end of the twisted wire is used to connect the positive and negative poles of the power supply. The heating power of the input resistance is determined. The rib prestress release temperature is the softening temperature of the epoxy resin. the

Example 6

The manufacturing method of the outer tube 3 made of glass fiber reinforced composite material in this embodiment is the same as that in Embodiment 5. The iron casing 20 is glued to the end of the outer pipe 3 with a modified high temperature resistant epoxy resin adhesive 21 . the

Next, a method of manufacturing the glass fiber reinforced composite material inner pipe 7 will be described. Several glass fibers are arranged in parallel in the same direction on the mandrel to form a bundle, and then the glass fiber inner tube is made by the method of Example 1. The insulated conductive heating wire 15 impregnated with epoxy resin glue is wound on the inner tube 7, and after the epoxy resin is cured, the conductive heating wire 15 is bonded on the surface of the steel wire to form the inner tube 7 with a heating element. the

In this embodiment, the adhesive 5 is epoxy resin with porcelain powder and quartz powder as filler and polyamide resin as curing agent. Mix epoxy resin with curing agent, accelerator and diluent with ceramic powder and quartz powder filler to form adhesive 5 and inject it into outer tube 3 . Dip-coat the outer surface of the inner tube 7 with strong ribs on the outer surface of the inner tube 7, then penetrate into the outer tube 3, first stretch the ribs in the inner tube 7, pre-press the inner tube 7, and then press the inner tube 7 to reach the stress value. The two ends of the pipe are anchored to complete the preloading of the inner pipe. The outer tube 3 is stretched with a tensioner, and the adhesive 5 is solidified after the stress reaches the design value. After the bonding agent reaches strength, loosen the outer tube 3 and the ribs. Connect the conductive heating wire 15 and the wire 22 at the end of the pre-stored stress tendon, and coat the hot-melt resin sealing glue 24 at the mouth of the casing 20 to complete the manufacture of the pre-stored stress tendon

Example 7

The pre-stored stress tendons produced in the above embodiments have a relatively large length and diameter, and the products include plates, rods, continuous long fibers, etc., and the heating method is direct electric heating, and the target body is concrete. This embodiment illustrates pre-stored stress short fiber tendons, the diameter of which is not greater than 3 mm, the heating method is electromagnetic induction heating, and the target body is concrete. the

Next, a method of manufacturing the glass fiber outer tube 3 will be described. Several glass fibers are twisted on the mandrel, soaked in the alumina adhesive, and the excess adhesive is scraped off, shaped by a molding die, and then the alumina adhesive is cured to form the glass fiber outer tube 3 . The glass fiber can also use phenolic resin as an adhesive, and heat-cure the phenolic resin to make the glass fiber outer tube 3 . It is also possible to directly use a high-strength glass fiber tube as the outer tube 3 . the

The core adopts ferromagnet that can be heated by electromagnetic induction—high-strength continuous steel fiber. the

In this embodiment, epoxy resin is used as the temperature-controlling adhesive, and polystyrene or polymethyl methacrylate may also be used as the adhesive. Mix the epoxy resin equipped with curing agent and accelerator to form adhesive glue solution 5. The outer tube 3 is filled with the glue solution, the high-strength steel wire is soaked in the binder solution, and then penetrated into the outer tube filled with the binder solution. Stretch the outer tube with a tensioner, and cure the adhesive after the stress reaches the design value. After the binder has reached strength, the outer tube is loosened to make a continuous fiber. Then it is cut into short fibers, as shown in Figure 51, wherein the outer tube 3 is a glass fiber outer tube, the core 4 is a steel fiber core, and the core 5 is an epoxy resin binder. During the cutting process, quick hardening polyurethane foam colloid 25 can be dotted on the ends of the prestored stress tendons, and other organic or inorganic foam glues can also be used to reserve elongation space for the core body to complete the manufacture of prestored stress short fiber tendons. The softening temperature of the binder is when the prestressed short fiber reinforcement is released. Since the iron core in the short fiber is small in volume, the eddy current heat generated by electromagnetic induction heating is not large, and the heating rate is limited. Therefore, the binder used in this embodiment can be Epoxy resin adhesive with low softening point (softening temperature between 60°C and 100°C) is used to reduce the impact on the performance of the substrate. the

Core body 4 adopts carbon fiber composite material or glass fiber composite material, and its manufacturing method is:

The surface is coated with iron-cobalt alloy material powder layer, and the powders are not insulated to increase the eddy current heating effect. The ferromagnetic powder can also use other ferrous alloys. After the core body is coated with the iron-cobalt alloy powder layer, epoxy resin is used as the binder 5, and the same penetration process as above is carried out. After the long fibers are made, they are cut into short fibers. During the cutting process, quick-hardening polyurethane foam can be applied to the ends of the pre-stored stress tendons, or other organic or inorganic foams can be used to reserve the stretch for the core 4. Long space, complete the manufacture of pre-stored stress short fiber tendons. the

Example 8

This embodiment illustrates pre-stored stress short fiber tendons, the diameter of which is not greater than 3 mm, the heating method is electromagnetic induction heating, and the target body is concrete. Ferromagnetic powder is directly added to the binder as a heating element, so the outer tube, inner tube or core are made of non-ferromagnetic materials. the

Outer pipe 3 adopts glass fiber pipe, and manufacturing method is the same as embodiment 7. The core body 4 is made of carbon fiber composite material, and its manufacturing method is as follows: arrange several pitch-based carbon fibers in parallel in the same direction, soak them in epoxy resin with polyamide resin as the curing agent, scrape off excess epoxy resin, and cure through the molding mold Into the core body 4. the

In this embodiment, the adhesive 5 adopts epoxy resin with polyamide resin as curing agent. Mix epoxy resin equipped with curing agent and iron-cobalt alloy material powder to form adhesive glue solution 5, fill the outer tube 3 with the glue solution, soak the core body 4 in the adhesive solution, and then stuff it into the adhesive glue that has been filled. In the outer tube 3 of the agent solution. The outer tube 3 is stretched, and the adhesive 5 is cured at room temperature after its stress reaches the design value and is maintained. After the binder 5 reaches strength, the outer tube 3 is loosened to make long fibers. Then it is cut into short fibers, as shown in Figure 51, in the cutting process, the end point of the pre-stored stress tendons can be coated with quick-hardening polyurethane foam glue 25, and the pre-stored stress short fiber tendons are completed. the

Example 9

This embodiment illustrates pre-stored stress short fiber tendons, the diameter of which is not greater than 3 mm, the heating method is electromagnetic induction heating, and the target body is concrete. The electromagnetic induction heating element adopts high-strength steel wire. the

The outer tube of this embodiment is made of glass fiber composite material, and the manufacturing method for assembling the glass fiber outer tube parts is the same as that in Example 8. The glass fiber outer tube is assembled from three outer tubes. The core body of this embodiment adopts high-strength steel wire. the

The method for manufacturing pre-stored stress tendons by splicing is described below. This manufacturing method is a combined manufacturing method in which stretching, joining, and curing are carried out simultaneously. The manufacturing method is as shown in Figure 35. On the left side of the forming hole, three stretched segments 11 and the unstretched core 4 pass through the forming mold, using modified thermoplastic polystyrene as the binder 5, and heating Injected into the splicing place, each component is pushed forward from the left side of the forming hole at the same speed, extruded through the forming hole, and reaches the solidification place to cool and solidify. After all solidification, loosen the tension at both ends to obtain pre-stored stress long fiber tendons . It is cut into short fibers, as shown in Figure 51, in the cutting process, the end of the pre-stored stress tendons can be coated with quick-hardening polyurethane foam glue 25 to complete the manufacture of pre-stored stress short fiber tendons. the

Similarly, when the core body 4 is made of carbon fiber composite material, the surface of the carbon fiber core body 4 is coated with iron-cobalt alloy powder as a heating element, and the manufacturing method of the pre-stored stress short fiber tendons is similar to the above-mentioned high-strength steel wire splicing manufacturing method. the

Example 10

This implementation illustrates the manufacturing method of the pre-stored stress tendons of the end-supported and anchored composite structure, and the target body of the example is concrete. The prestress release method is to release the prestress when the temperature of the binder in the anchorage area is softened. Figures 38 to 43 are cross-sectional views of the pre-stored stress tendons of the end-anchored composite structure. In the three figures, Figures 38 and 39 show the manufacturing method of the pre-stored stress tendons. Several continuous glass fibers are arranged in parallel or twisted in the same direction on the mandrel, soaked in the epoxy resin glue with polyamide resin as the curing agent, pultruded through the forming hole, and cured the epoxy resin. Outer tube3. Or put it in the polyglycidylamine type epoxy resin mixed glue solution with curing agent, accelerator and diluent to soak, scrape off the excess epoxy resin, pass through the thermoforming mold, and enter the curing oven for curing at 130°C , to make the outer tube 3. The iron casing 20 is glued to the end of the outer pipe 3 by using a modified high temperature resistant epoxy resin glue 21 . The core is made of high-strength steel wire. the

The anchoring adhesive at the end of the pre-stored stress tendon is epoxy resin with porcelain powder and quartz powder as filler and polyamide resin as curing agent. Method 1: Insert the core body 4 into the outer tube 3, stretch the outer tube 3 to reach the stress value and maintain it. A pin 13 dipped in epoxy resin glue is inserted into the end of the outer tube 3. After the epoxy resin is cured, the tension of the outer tube is loosened to complete the manufacture of the stressed structure. Method 2: Insert the core body 4 into the outer tube 3, stretch the outer tube 3, and compress the core body 4. After the two reach the stress value, insert a pin 13 soaked in epoxy resin glue at the end of the outer tube 3, And close to the core body 4, after the epoxy resin is cured, loosen the outer tube 3 and the core body 4 to complete the manufacture of the stressed structure. Connect the lead wire 22 and the conductive heating wire 15, and then smear the hot-melt resin sealing glue 24 on the mouth of the outer tube 3 to complete the manufacture of the pre-stored stress tendons. the

The manufacturing method of pre-existing stress tendons shown in Fig. 40 and 41. The manufacturing method of outer tube 3 is the same as the manufacturing method of pre-stored stress tendons shown in Figures 38 and 39. The iron casing 20 is glued to the end of the outer pipe 3 by using a modified high temperature resistant epoxy resin glue 21 . The core is made of high-strength steel wire. As described in the manufacturing method of pre-stored stress tendons shown in Figures 38 and 39, after the stress structure is manufactured, connect the wire 22 and the conductive heating wire 15, and then smear the hot-melt resin sealing glue 24 on the mouth of the casing 20 to complete the pre-stored stress tendons. Fabrication of stress tendons. the

The manufacturing method of the prestored stress tendon shown in Fig. 42,43. The manufacturing method of outer tube 3 is the same as the manufacturing method of pre-stored stress tendons shown in Figures 38 and 39. The iron casing 20 is glued to the end of the outer pipe 3 by using a modified high temperature resistant epoxy resin glue 21 . The core is made of high-strength steel wire. the

The anchoring adhesive at the end of the pre-stored stress tendon is epoxy resin with porcelain powder and quartz powder as filler and polyamide resin as curing agent. The core body 4 is inserted into the outer tube 3, and the outer tube 3 is stretched to reach and maintain the stress value. Insert the sealing sheet 28 at the end of the outer tube 3 to prevent the epoxy resin from flowing into the gap 10 between the outer tube and the core body, then insert a heating element made of conductive heating wire 15 into the anchorage area at the end of the outer tube 3, and then inject epoxy Resin glue. After the epoxy resin is cured, loosen the tension of the outer tube to complete the manufacture of the stressed structure. Connect the conductive heating wire 15 out of the casing, and then smear a hot-melt resin sealing glue 24 on the mouth of the casing 20 to complete the manufacture of pre-stored stress tendons. the

Similarly, the outer tube 3 and the core body 4 can adopt fiber-reinforced composite materials such as carbon fiber and glass fiber, and the outer tube 3 can also use high-strength steel pipes, and their manufacturing methods can use the outer tube 3 and the core body 4 described in the above embodiments. method of making. The outer tube 3 and the core body 4 of various materials can be reasonably combined to form pre-stored stress tendons. The pin 13 material can adopt various core body materials or adhesive 5. When choosing fiber media, we can choose various reasonable organic or inorganic binders. The surface of the core body 4 at the gap can be processed to increase slip, so as to reduce the friction coefficient of the internal and external components. The above pre-stored stress tendons can be twisted into twisted wires, and the wires 22 of the pre-stored stress tendons at one end of the twisted wires are connected to each other, and the wires 22 at the other end of the twisted wires are used to connect the positive and negative poles of the power supply. The output voltage is determined by the heating power of the connected resistor. The prestress release temperature of the prestored stress tendons in this embodiment is the softening temperature of the epoxy resin. the

The pre-stored stress tendons shown in Fig. 7 to Fig. 28 and Fig. 38 to Fig. 51 are symmetrical pre-stored stress tendons. For the prestored stress tendons that reserve the telescopic gap 6 and adopt the full interface anchorage of the casing 20, and when its length is not very long, the telescopic gap 6 can be reserved at one end of the tendon and the casing 20 is adopted, and the outer wall of the other end The tube is flush with the core material, and the wires can be terminated from this end. For the pre-existing stress tendons anchored at the end, a telescopic gap 6 can be reserved at one end of the tendon or a protective sleeve 20 can be used, and an anchor release device-heating body can be set only at this end, while no heating body can be set up at the other end . Therefore, for the prestress release of asymmetric prestressed tendons, the core material slides from one end of the outer tube to the other end, unlike the core material of symmetrical prestored stress tendons that slides to both ends. the

Pre-existing stress tendons use expansion gaps or casing facilities to ensure the expansion space of the inner tube or core body, but it is not so easy to make pre-existing stress short fiber tendons, because short fiber tendons are cut from long fiber tendons, and pre-existing stress tendons The inner and outer structures are flat and without shortage, so it is difficult to stretch the gap at the end or install the casing. In order to solve this problem, a compressible body that is easy to compress and has a suitable strength, such as a cap and a resin foam body, can be placed at the end of the pre-stored stress tendon. Rapid curing polyurethane foam, polystyrene foam, etc. shown in Example 9. The cap or foam can be installed on the end by spraying, painting or sticking, so as to reserve space for the elongation of the inner tube or core and improve the efficiency of prestressing. the

As described in the embodiment, the above-mentioned pre-stored stress tendons can be polygonal, circular, annular, elliptical, special-shaped, etc., and the cross-sectional shape of the pre-stored stress tendons can be made by any combination of the structural parts. . According to the cross-sectional size of pre-stored stress tendons, the size can be as large as rods and plates, and as small as very thin fibers. In order to improve the bonding force, friction force and mechanical bite force of each layer of the interface and increase the effect of prestressing, the surface of the outer tube, core body, inner tube, pin, casing and sleeve can be specially treated to make it uneven state. For example, it can be made into a thread shape to increase the bite force and prevent sliding between interfaces. In order to make the prestressing effect better, the end of the pre-existing stress tendon can also be bent, the end is enlarged, and the cross-section is deformed to improve the stress efficiency. The components of the pre-stored stress tendons include outer tube, core body, inner tube, pin, casing, sleeve, heating element, etc. These parts can be a combination or a spliced body, and each component can be determined according to the manufacturing method of the pre-stored stress tendons. Combination or combination of components. the

The above-mentioned embodiments should be understood that these embodiments are only used to illustrate the utility model more clearly, and are not intended to limit the scope of the utility model. After reading the utility model, those skilled in the art will understand each aspect of the utility model The modifications of all equivalent forms all fall within the scope defined by the appended claims of the present application. the

Claims (9)

1. A composite structure pre-stored stress tendon, which comprises at least an outer tube with a hole and at least one core, characterized in that: the core is placed in the outer tube hole, the outer tube and the core One is a tension body, the other is a compression body, and the outer tube and the core body are anchored and connected by one of the bonded anchoring method and the composite bonded anchoring method to form a tension-compression balance body. 2. The pre-stored stress tendons of the composite structure according to claim 1, characterized in that: the tension-compression balance body is provided with a heating element that controls the bonding and anchoring strength of the binder in the tension-compression balance body through temperature rise. 3. The composite structure pre-stored stress tendon according to claim 1, characterized in that, the outer tube and the core are directly connected by anchoring to form a tension-compression balance body, a heating element is arranged in the tension-compression balance body, and the core The heat change temperature of the body material is lower than the limit service temperature of the outer tube. 4. The composite structure pre-stored stress tendon according to claim 1, 2 or 3, characterized in that there is a gap between the outer tube and the core body or the end of the core body has a telescopic gap, the gap or the telescopic gap With adhesive. 5. The composite structure pre-stored stress tendon according to claim 1, 2 or 3, characterized in that, the outer tube and the core body are anchored by adhesive pin anchors to form a tension-compression balance body, and the adhesive pin The pins in the sub-anchor are bonded in place at the end of the outer pipe. 6. The composite structure pre-stored stress tendon according to claim 1, 2 or 3, characterized in that the outer tube and the core are anchored by an adhesive cap tube anchor or an adhesive sleeve anchor to form a tension-compression The balance body, the cap cylinder in the adhesive cap cylinder anchor or the sleeve in the adhesive sleeve anchor is bonded to the end of the core. 7. The composite structure pre-stored stress tendon according to claim 1, 2 or 3, characterized in that, the outer tube is assembled by at least one segment through an adhesive, and the radial segment layer of the outer tube The number is one layer or multiple layers. 8. The composite structure pre-stored stress tendon according to claim 2 or 3, characterized in that the heating element is an outer tube or a core. 9. The composite structure pre-stored stress tendon according to claim 2 or 3, characterized in that the heating element is electrically connected to the wire.

Images