CN102900094B - Transmission tower plate-type three-rope foundation structure - Google Patents

Abstract

The invention discloses a tower plate type three-cable foundation structure for transmission poles, which comprises an upper plate laid on the ground surface and three lower plates buried underground, and is characterized in that a cable is passed between the upper plate and each lower plate respectively. The steel strands are connected, and the three lower plates are arranged in a straight line, the length of the steel strands in the middle is greater than the length of the steel strands on both sides, and the lengths of the steel strands on both sides are equal. The tower plate type three-cable foundation structure of the transmission pole provided by the present invention, the upper plate is used as a basic protective cap, has the advantages of perfect and clear force transmission boundary conditions, fully exerting the physical and mechanical properties of various materials, saving investment, high safety and reliability, and simple construction, etc. , when the physical and mechanical properties of the foundation soil of the line are poor and the uplift load is large, the safety and reliability of the foundation are greatly improved due to the use of three anchor cables, so this foundation is suitable for large uplift forces and poor physical and mechanical properties of the foundation soil Loess areas, such as the foundation of lines with voltage levels above 330kV.

Description

Transmission pole tower type three-cable foundation structure

technical field

The invention relates to a power transmission pole and tower equipment, specifically a foundation fixing structure for a power transmission pole and tower.

Background technique

In large-thickness loess areas, the foundations of pole towers mainly adopt "big excavation" foundations, digging and bottom expansion foundations, and explosive expansion pile foundations. "Large excavation" foundation category refers to the foundation buried in the pre-excavated foundation pit and the backfill soil is compacted. It uses the disturbed backfill soil to form an uplift-resistant soil body to maintain the uplift stability of the foundation. Excavated and expanded bottom foundation refers to the foundation that is filled with concrete and steel skeleton in the soil tire excavated by machinery or manually. It maintains the uplift and stability of the foundation with the naturally formed uplift-resistant soil. Explosive expansion pile foundation refers to the short pile foundation with concrete and steel skeleton poured into the enlarged end of the soil tire formed by explosion expansion. The uplift soil is basically close to the undisturbed natural soil.

The main size of the "big excavation" foundation is determined by its uplift stability. In order to meet the requirements of uplift stability, the size of the foundation must be increased, which increases the cost of the foundation. The damage is also greater. Excavation and bottom expansion foundations are suitable for cohesive soil without water infiltration into the foundation pit. At the same time, the pile foundation specification stipulates that if the foundation adopts pile foundation, the bearing layer of the foundation must pass through collapsible loess, so this foundation is not suitable for large thickness Collapsible loess area. Explosive expansion pile foundation construction is more difficult, and there are certain difficulties in process and dimension inspection.

Contents of the invention

In order to solve the above problems, the present invention provides a tower-plate type three-cable foundation structure for transmission poles suitable for the thick loess area.

The purpose of the present invention is specifically achieved through the following technical solutions:

The tower-type three-cable foundation structure of transmission poles includes an upper slab laid on the ground and three lower slabs buried in the ground. The lower plate is arranged in a straight line, the length of the steel strands in the middle is greater than the length of the steel strands on both sides, and the lengths of the steel strands on both sides are equal, and each of the strands between the upper plate and the lower plate There is a rubber sleeve outside the steel strand, and the two ends of each rubber sleeve are in contact with the upper plate and a lower plate respectively, and the inside of the rubber sleeve is filled with anti-corrosion filler; the steel strand An anchor head is provided at both ends, an upper bearing pad is provided between the upper anchor head and the upper plate, and a lower bearing pad is provided between the lower anchor head and the lower plate; the upper bearing pad located in the middle Four symmetrically arranged anchor bolts are poured on the plate, and the anchor bolts penetrate the upper plate and are fixedly connected with the pouring backing plate poured on the bottom surface of the upper plate. Both the upper plate and the lower plate are poured and formed with reinforced concrete materials.

The upper board adopts a rectangular structure, and the area of the upper board is much larger than the sum of the areas of the three lower boards.

The tower plate type three-cable foundation structure of the transmission pole provided by the present invention, the upper plate is used as a basic protective cap, has the advantages of perfect and clear force transmission boundary conditions, fully exerting the physical and mechanical properties of various materials, saving investment, high safety and reliability, and simple construction, etc. , when the physical and mechanical properties of the foundation soil of the line are poor and the uplift load is large, the three-cable foundation structure can reduce the excavation depth compared with the single-cable and double-cable foundation structures. Since three anchor cables are used, the foundation safety is greatly improved and reliability, so the foundation is suitable for loess areas with large uplift force and poor physical and mechanical properties of the foundation soil, such as the foundation of lines with voltage levels above 330kV.

The foundation structure is a flexible foundation, which can improve the ability of the tower to resist dynamic loads; at the same time, it can reduce the amount of spoil and protect the ecological environment; and it is easy to disassemble. If the foundation is no longer used, the steel strands can be cut directly. It only needs to dig out the upper plate, which reduces the amount of foundation demolition work; and the load transmission mechanism can also be used as the ground wire. The load transfer of the foundation structure is clear, and the structure calculation and construction are relatively simple. The use of three anchor cables can improve the reliability of the foundation. When one anchor cable yields or fails, the other two anchor cables can bear the uplift load of the foundation. In the design, the pull-out force of each anchor cable can be required to meet half Pull-up load requirements.

Description of drawings

The present invention will be described in further detail below according to the drawings and embodiments.

Fig. 1 is a structural diagram of the transmission pole-tray type three-cable foundation structure according to the embodiment of the present invention.

Fig. 2 is a top view of the ground surface of the transmission pole tower-type three-cable foundation structure according to the embodiment of the present invention.

Detailed ways

As shown in Figures 1-2, the transmission pole tower-type three-cable foundation structure according to the embodiment of the present invention includes an upper plate 1 laid on the ground surface and three lower plates 2 buried underground, the upper plate 1 and each The lower plates 2 are respectively connected by a steel strand rope 3, and the three lower plates 2 are arranged in a straight line, and the length of the steel strand rope 3 in the middle is greater than the length of the steel strand rope 3 on both sides. The lengths of the steel strand ropes 3 on the side are equal, and each steel strand rope 3 between the upper plate 1 and the lower plate 2 is provided with a rubber sleeve 4 outside, and each of the two ends of the rubber sleeve 4 is respectively In contact with the upper plate 1 and a lower plate 2, the inside of the rubber sleeve 4 is filled with anti-corrosion filler 5; the two ends of the steel strand 3 are respectively provided with an anchor head 61, 62, and the upper anchor head 61 There is an upper bearing backing plate 71 between the upper plate 1 and a lower supporting backing plate 72 between the lower anchor head 62 and the lower plate 2; four symmetrical Anchor bolts 8 are arranged, and the anchor bolts 8 penetrate the upper plate 1 and are fixedly connected with the pouring backing plate 9 poured on the bottom surface of the upper plate 1 . Both the upper plate 1 and the lower plate 2 are poured and formed with reinforced concrete materials. The upper board 1 adopts a rectangular structure, and the area of the upper board 1 is much larger than the sum of the areas of the three lower boards 2 .

The tower plate type three-cable foundation structure of the transmission pole provided by the present invention, the upper plate is used as a basic protective cap, has the advantages of perfect and clear force transmission boundary conditions, fully exerting the physical and mechanical properties of various materials, saving investment, high safety and reliability, and simple construction, etc. , when the physical and mechanical properties of the foundation soil of the line are poor and the uplift load is large, the three-cable foundation structure can reduce the excavation depth compared with the single-cable and double-cable foundation structures. Since three anchor cables are used, the foundation safety is greatly improved and reliability, so the foundation is suitable for loess areas with large uplift force and poor physical and mechanical properties of the foundation soil, such as the foundation of lines with voltage levels above 330kV.

The foundation structure is a flexible foundation, which can improve the ability of the tower to resist dynamic loads; at the same time, it can reduce the amount of spoil and protect the ecological environment; and it is easy to disassemble. If the foundation is no longer used, the steel strands can be cut directly. It only needs to dig out the upper plate, which reduces the amount of foundation demolition work; and the load transmission mechanism can also be used as the ground wire. The load transfer of the foundation structure is clear, and the structure calculation and construction are relatively simple. The use of three anchor cables can improve the reliability of the foundation. When one anchor cable yields or fails, the other two anchor cables can bear the uplift load of the foundation. In the design, the pull-out force of each anchor cable can be required to meet half Pull-up load requirements.

Claims (2)

1. the board-like three rope foundation structures of transmission tower, comprise the lower plate that a upper plate being laid on earth's surface and three are embedded in underground, it is characterized in that, connect between described upper plate and each lower plate respectively by a steel strand rope, three described lower plates are that yi word pattern is arranged, the length being positioned at middle steel strand rope is greater than the length of the steel strand rope being positioned at both sides, the length of the steel strand rope of both sides is equal, during if do not re-used dismounting, is directly cut off by steel strand, excavate upper plate

Described steel strand rope outside between upper plate and each lower plate is provided with a gum cover pipe, and the two ends of each described gum cover pipe contact with a lower plate with upper plate respectively, are filled with anticorrosive packing at described glue inside pipe casing,

Described upper plate, lower plate are Reinforced Concrete Materials moulding by casting,

The two ends of described steel strand rope are respectively equipped with an anchor head, are provided with carrying backing plate between the anchor head on top and upper plate, are provided with lower carrying backing plate between the anchor head of bottom and lower plate,

Be positioned at middle described on carry backing plate upper and have four stone bolt be arranged symmetrically with, described stone bolt runs through upper plate, and is fixedly connected with the cast backing plate being cast in upper plate bottom surface.

2. the board-like three rope foundation structures of transmission tower as claimed in claim 1, it is characterized in that, described upper plate adopts rectangular structure, and the area of upper plate is greater than the area sum of three lower plates.