A method for correcting the settlement and deviation of a power transmission tower

Abstract

The application discloses a power transmission tower settlement deviation rectification method, relates to the technical field of power transmission tower deviation rectification, and solves the problems of difficult construction and existing settlement risks of the existing power transmission tower deviation rectification, improves the firmness and stability of the plate type foundation, and reduces the cost, and the specific scheme is as follows: four square protection stay wires are arranged on the power transmission tower; foundation pits are sequentially excavated below four corners of a plate type foundation at the bottom of a to-be-jacked leg of the power transmission tower, a spiral anchor is first installed in each foundation pit after the excavation of the foundation pit is completed, a steel beam is installed at the top end of the spiral anchor, a hydraulic jack is placed on the steel beam to support the corner of the plate type foundation, and then the excavation of the subsequent foundation pit and the corner support are carried out; after the plate type foundation is jacked to a specified height through the hydraulic jack, the hydraulic jack is replaced by a cushion block; after all the hydraulic jacks are taken out, grouting and backfilling are carried out in the foundation pit.

Description

Technical Field

[0001] This invention relates to the field of transmission tower alignment technology, and in particular to a method for correcting the settlement of transmission towers. Background Technology

[0002] Transmission towers erected in mountainous areas face several issues related to tower settlement. For example, when the mountain rock is limestone or soluble rock, karst caves easily form due to groundwater erosion. Similarly, in mining areas like coal mines, abandoned mine shafts may exist. Damage to the tower foundation's top surface drainage slope and facilities caused by industrial construction such as reservoirs and dams, as well as agricultural production, allows water to seep into the backfill and subgrade, disrupting the original geological balance. Furthermore, insufficient geological exploration and a lack of comprehensive understanding of unique geological conditions lead to inadequate design considerations for foundation depth, subgrade, and compaction, underestimating the impact of adverse underground geological conditions and lacking appropriate methods for handling hidden floods and pits. Inadequate foundation treatment during construction results in insufficient compaction of the backfill and lime-soil subgrade, leading to foundation and backfill density not meeting design requirements. This results in substandard construction surfaces and drainage designs, potentially causing water seepage into the backfill layer. Therefore, under the above conditions, the transmission towers erected are very prone to the load capacity of the upper part of the transmission tower reaching and exceeding the limit of the foundation and bearing layer after the transmission tower is in operation due to underground rock cavities, which in turn damages the foundation and causes the tower legs and even the entire transmission tower to settle.

[0003] Existing methods for correcting transmission tower deviations often involve separating the tower legs from the foundation, using jacks to lift the legs before constructing the foundation or replacing the legs. This method is difficult to implement and damages the connection between the legs and the foundation. Furthermore, it fails to adequately reinforce the foundation, leaving the transmission tower prone to settlement. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method for correcting the settlement of transmission towers. This method utilizes a hydraulic jack supported by a foundation composed of a spiral anchor and steel beams to lift the settled transmission tower, and combines this with grouting backfilling to reinforce the foundation. This solves the problems of difficult construction and the continued risk of settlement in existing transmission tower correction methods.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0006] This invention provides a method for correcting the settlement of transmission towers, as detailed below:

[0007] Install four-sided protective guy wires on the transmission towers;

[0008] Excavate foundation pits in sequence below the four corners of the slab foundation at the bottom of the support legs to be lifted on the transmission tower. After each foundation pit is excavated, install a spiral anchor in the foundation pit, install a steel beam at the top of the spiral anchor, and place a hydraulic jack on the steel beam to support the corners of the slab foundation. Then carry out the excavation of the subsequent foundation pits and corner support.

[0009] After the slab foundation is lifted to the designated height using hydraulic jacks, the hydraulic jacks are replaced with pad blocks.

[0010] After all the hydraulic jacks were removed, grout was poured into the pit and backfilled.

[0011] As a further implementation, during the excavation of the foundation pit, a steel plate is inserted below the slab foundation and in contact with its bottom surface, with the steel plate positioned above the steel beam.

[0012] As a further implementation, the spiral anchor is directly inserted into the rock layer below the slab foundation. The spiral anchor consists of an anchor rod and several anchor discs fixedly installed on the anchor rod, and the steel beam is fixedly connected to the top of the spiral anchor.

[0013] As a further implementation, the center of the steel beam is aligned vertically with the center of the corresponding corner of the slab foundation.

[0014] As a further implementation, a hydraulic jack is provided at the center of each of the steel beams, with the top of the piston rod of the hydraulic jack contacting the steel plate.

[0015] As a further implementation, a rubber gasket is provided between the hydraulic jack and the steel beam.

[0016] As a further implementation, all steel beams under the same slab foundation are at the same horizontal height and the initial extension length of the hydraulic jacks is the same.

[0017] As a further implementation, the pad is prefabricated from high-strength concrete, and the overall height of the pad is equal to the distance between the bottom of the slab foundation and the bottom of the pit after jacking. After the pad is placed in the pit and fixed, the hydraulic jack in the corresponding pit is taken out.

[0018] As a further implementation method, grouting is performed in the foundation pit to form a new foundation, and backfilling is carried out after the new foundation has solidified.

[0019] As a further implementation, the pull wire is in a relaxed state.

[0020] The beneficial effects of the present invention are as follows:

[0021] (1) This invention utilizes a hydraulic jack composed of a spiral anchor and steel beams to lift the settled transmission tower, and combines it with grouting backfilling to reinforce the foundation. The use of spiral anchors improves the compressive and tensile bearing capacity of the foundation at the bottom of the tower legs, making the foundation at the bottom of the tower legs more solid and stable. Only the foundation pits below the corners of the slab foundation are excavated sequentially, and spiral anchors, steel beams and hydraulic jacks are constructed after each foundation pit is excavated. It is not necessary to completely excavate the soil at the bottom of the slab foundation, which effectively ensures the stability of the slab foundation during the foundation pit excavation process, reduces the difficulty of foundation pit excavation, and avoids damage to the slab foundation.

[0022] (2) The steel plate under the slab foundation of the present invention plays a role in dispersing the force, effectively avoiding the problem of failure of the jacking operation caused by the force damage at the corners of the slab foundation 4.

[0023] (3) The spiral anchor of the present invention is inserted into the rock layer below the slab foundation, which effectively avoids the problem that the foundation cannot guarantee sufficient compressive bearing capacity due to the deep hole.

[0024] (4) The spiral anchor of the present invention is small in size, light in weight and strong in bearing capacity, which greatly reduces the difficulty of material transportation and construction, reduces the amount of engineering work, and is more suitable for mountainous areas and other scenarios where transportation and construction are inconvenient.

[0025] (5) The present invention has a rubber gasket between the hydraulic jack and the steel beam. On the one hand, it reduces the friction of the contact surface, and on the other hand, it plays a buffering role, reducing the instantaneous impact of the downward pressure on the steel beam and the foundation below, so that the force transmission during the lifting process is more uniform.

[0026] (6) In this invention, all steel beams under the same slab foundation are at the same horizontal height and the initial extension length of the hydraulic jacks is the same, so as to achieve a stable state. This allows the hydraulic jacks to more accurately control the lifting height of the transmission tower, and the lifting force is equal, which further ensures the stability of the tower body during the lifting process, making the lifting method simpler.

[0027] (7) The present invention uses pad blocks to replace hydraulic jacks, which enables hydraulic jacks to be reused and greatly reduces construction costs. Attached Figure Description

[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0029] Figure 1 This is a schematic diagram of the installation of four-sided protective guy wires on the transmission tower before lifting it, according to one or more embodiments of the present invention.

[0030] Figure 2 This is a top view structural diagram of the transmission tower settlement correction construction according to one or more embodiments of the present invention;

[0031] Figure 3 This is a front view structural schematic diagram of the transmission tower settlement correction construction according to one or more embodiments of the present invention;

[0032] Figure 4 This is a partially enlarged structural schematic diagram of the transmission tower settlement correction construction according to one or more embodiments of the present invention;

[0033] Figure 5 This is a three-dimensional structural schematic diagram of the transmission tower settlement correction construction according to one or more embodiments of the present invention;

[0034] In the diagram: the spacing or dimensions between parts have been exaggerated to show their positions; the diagram is for illustrative purposes only.

[0035] The components include: 1. Spiral anchor; 2. Steel beam; 3. Hydraulic jack; 4. Plate foundation; 5. Shim; 6. Anchor plate; 7. Pad block. Detailed Implementation

[0036] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0037] As described in the background section, existing methods for correcting transmission tower deviations often involve separating the tower legs from the foundation, using jacks to lift the tower legs before constructing the foundation or replacing the tower legs. This method is difficult to implement and damages the connection between the tower legs and the foundation. Furthermore, it does not effectively reinforce the foundation and still results in the problem of transmission tower settlement. To address these technical issues, this invention proposes a method for correcting transmission tower settlement.

[0038] Example 1

[0039] In a typical embodiment of the present invention, such as Figures 1-5 As shown, a method for correcting the settlement of transmission towers is proposed, as follows:

[0040] (1) Install four-sided protective guy wires on the transmission tower to stabilize its overall structure.

[0041] Depending on the height of the transmission tower, four or eight guy wires are installed around its perimeter. Each guy wire maintains a 45° angle with the direction of the transmission line on the tower, and at the same time forms an angle of less than 45° with the ground. The guy wires are then fixedly connected to the pre-embedded anchor bolts.

[0042] It is important to note that the guy wires should be kept as slack as possible in preparation for the excavation of the foundation pit under the tower legs.

[0043] (2) Excavation of the foundation pit

[0044] Excavate foundation pits in sequence below the four corners of the plate foundation 4 of the support leg to be lifted of the transmission tower, and insert steel plates that contact the bottom surface of the plate foundation 4.

[0045] (3) Drill holes and install spiral anchors 1

[0046] Retaining walls are constructed around the foundation pit to ensure the stability of the soil around the pit. Holes are drilled in the retaining walls and anchor bolts are installed and grout is injected to improve the strength and stability of the retaining walls.

[0047] Understandably, whether or not to construct a retaining wall can be determined based on the actual depth and size of the foundation pit, and no further restrictions are imposed here.

[0048] The spiral anchor 1 is driven directly into the rock layer below the slab foundation 4, which avoids the problem that the foundation cannot guarantee sufficient compressive bearing capacity due to the deep hole. The spiral anchor 1 consists of an anchor rod and several anchor plates 6 fixedly installed on the anchor rod. The steel beam 2 is placed in the foundation pit and fixedly connected to the top of the embedded spiral anchor 1. Each steel beam 2 is connected to at least one spiral anchor 1 at each end.

[0049] The radius of the anchor plate 6 is determined according to actual needs. The spiral anchor 1 is driven directly into the rock layer to enhance the compressive and tensile bearing capacity of the foundation at the bottom of the tower leg, making the foundation at the bottom of the tower leg more solid and stable.

[0050] It should be noted that the spiral anchor 1 should be buried in a hard and reliable rock layer. When the surface rock is weathered, eroded or even has cavities, the length of the anchor rod and the number of anchor discs 6 should be increased to ensure the reliability of the foundation of the spiral anchor 1.

[0051] Among them, a steel beam 2 is provided at the bottom of each of the four corners of the slab foundation 4 at the bottom of the tower leg to be lifted. The steel beam 2 is located below the steel plate, and the center of the steel beam 2 is aligned vertically with the center of the corresponding corner of the slab foundation 4.

[0052] Steel beam 2 is made of high-strength I-beams and other shapes of steel to provide sufficient support and resist downward pressure.

[0053] Because the spiral anchor 1 is small in size, light in weight and has strong pressure bearing capacity, it greatly reduces the difficulty of material transportation and construction, reduces the amount of project, and is more suitable for mountainous areas and other scenarios where transportation and construction are inconvenient.

[0054] The anchor plate 6 is in direct contact with the soil, and there is friction between the two, which can provide some uplift bearing capacity. In addition, the spiral anchor plate can firmly anchor its lower part into the rock, ensuring the stability of the foundation and increasing the bearing area of ​​the foundation. It can transfer the force to the rock. Since the rock has a large bearing capacity, the spiral anchor 1 can provide a large compressive bearing capacity.

[0055] (4) Lifting tower legs

[0056] A hydraulic jack 3 is placed at the center of each steel beam 2. All hydraulic jacks 3 under the same slab foundation 4 are adjusted so that the top of the piston rod of all hydraulic jacks 3 under the same slab foundation 4 is in contact with the steel plate at the bottom of the same slab foundation 4.

[0057] Then, start the hydraulic jack 3 to lift the tower legs (or plate foundation 4) of the transmission tower to the designated position.

[0058] The lifting operation of the hydraulic jack 3 can be controlled by computer. It has the advantages of convenient control, uniform and adjustable lifting force, high lifting accuracy, strong adaptability to soil and environment, and wide application range. It is especially suitable for transmission towers with uneven settlement.

[0059] Understandably, the lifting speed of the hydraulic jack 3 is determined based on actual needs, and no further restrictions are imposed here.

[0060] Before placing the hydraulic jack 3, a shim 5 needs to be placed at the center of the corresponding steel beam 2. The shim 5 is made of rubber, which serves to reduce the friction of the contact surface and to act as a buffer, reducing the instantaneous impact of the downward pressure on the steel beam and the foundation below, so that the force transmission during the jacking process is more uniform.

[0061] The steel plates serve to disperse the force, effectively preventing damage to the corners of the slab foundation 4 that could lead to jacking failure.

[0062] When installing steel beams 2 and hydraulic jacks 3, attention should be paid to the even distribution of the tower weight. That is, all steel beams 2 under the same slab foundation 4 should be at the same horizontal height and the initial extension length of hydraulic jacks 3 should be the same to achieve a stable state. This allows hydraulic jacks 3 to more accurately control the lifting height of the transmission tower, and the lifting force is equal, which further ensures the stability of the tower during the lifting process and makes the lifting method simpler.

[0063] It should be noted that the installation of the spiral anchor 1, steel beam 2 and hydraulic jack 3 should be carried out according to the excavation sequence of the foundation pits below the four corners of the slab foundation 4. That is, after the foundation pit at one corner is excavated, the corresponding spiral anchor 1, steel beam 2 and hydraulic jack 3 should be installed first, and then the excavation of the foundation pits at the subsequent corners and the support of the corresponding corners should be carried out in this order.

[0064] (5) Foundation reinforcement

[0065] After the tower leg is lifted to the designated position, a prefabricated pad 7 is placed near the hydraulic jack 3. The pad 7 is made of high-strength concrete. The overall height of the pad 7 is equal to the distance between the bottom of the slab foundation 4 and the bottom of the pit after lifting. The pad 7 is used to replace the hydraulic jack 3. The pad is fixed and the hydraulic jack 3 is removed.

[0066] It is understandable that the spacer block 7 can be fixed by grouting or other methods. The specific fixing method can be determined according to actual needs, and the concrete strength used for the precast spacer block needs to be determined according to actual needs. No further restrictions will be imposed here.

[0067] After all the hydraulic jacks 3 are removed, grout is poured under the bottom steel plate of the slab foundation 4 (i.e., inside the foundation pit) to form a new foundation. After the new foundation has solidified and cured, the foundation pit is refilled.

[0068] Plain concrete can be used for grouting. When fine aggregate concrete is used, an appropriate amount of expansion agent should be added, with the amount being 6% to 8% of the cement content, to ensure that the concrete strength can still meet the design requirements after the expansion agent is added.

[0069] In this embodiment, the bottom of the four corners of the slab foundation 4 is excavated and supported in sequence, which effectively ensures the stability of the slab foundation 4 during construction, greatly improves construction safety, reduces the amount of excavation, reduces environmental damage, requires less grouting, saves costs, and, in conjunction with the use of the spiral anchor 1, improves the compressive bearing capacity of the spiral anchor 1. The rigidity and strength of the structure can be improved without increasing the size of the pile cross-section, which greatly reduces the construction difficulty and cost.

[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for correcting settlement of transmission towers, characterized in that, Specifically as follows: Install four-sided protective guy wires on the transmission towers; Excavate foundation pits in sequence below the four corners of the slab foundation at the bottom of the support leg to be lifted of the transmission tower, and insert steel plates that contact the bottom surface of the slab foundation. Retaining walls are installed around the perimeter of the excavation pit to ensure the stability of the soil around the pit. After each foundation pit is excavated, a spiral anchor is first installed inside the foundation pit. The spiral anchor is directly inserted into the rock layer below the slab foundation. The spiral anchor consists of an anchor rod and several anchor discs fixedly installed on the anchor rod. A steel beam is installed at the top of the spiral anchor and is fixedly connected to the top of the spiral anchor. Hydraulic jacks were placed on the steel beams to support the corners of the slab foundation before the subsequent excavation of the foundation pit and corner support were carried out. All steel beams under the same slab foundation are at the same horizontal height and the initial extension length of the hydraulic jacks is the same; The installation of spiral anchors, steel beams, and hydraulic jacks is carried out according to the excavation sequence of the foundation pits below the four corners of the slab foundation. That is, after the foundation pit at one corner is excavated, the corresponding spiral anchors, steel beams, and hydraulic jacks are installed first, and then the excavation of the foundation pits at the subsequent corners and the support of the corresponding corners are carried out in the same order. After the slab foundation is lifted to the specified height by hydraulic jacks, the hydraulic jacks are replaced with pad blocks. After all the hydraulic jacks were removed, grout was poured into the pit and backfilled.

2. The method for correcting settlement of transmission towers according to claim 1, characterized in that, During the excavation of the foundation pit, a steel plate is inserted below the slab foundation to contact its bottom surface, with the steel plate positioned above the steel beam.

3. The method for correcting settlement of transmission towers according to claim 1, characterized in that, The center of the steel beam is aligned vertically with the center of the corresponding corner of the slab foundation.

4. The method for correcting settlement of transmission towers according to claim 2, characterized in that, A hydraulic jack is installed at the center of each steel beam, with the top of the piston rod of the hydraulic jack in contact with the steel plate.

5. The method for correcting settlement of transmission towers according to claim 1, characterized in that, A rubber gasket is provided between the hydraulic jack and the steel beam.

6. The method for correcting settlement of transmission towers according to claim 1, characterized in that, The pad is precast from high-strength concrete. The overall height of the pad is equal to the distance between the bottom of the slab foundation and the bottom of the pit after jacking. After the pad is placed in the pit and fixed, the hydraulic jack in the corresponding pit is taken out.

7. The method for correcting settlement of transmission towers according to claim 1, characterized in that, Grouting is performed inside the foundation pit to form a new foundation. After the new foundation has solidified, backfilling is carried out.

8. The method for correcting settlement of transmission towers according to claim 1, characterized in that, The pull wire is in a relaxed state.

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