A method for controlling the deformation of underground diaphragm walls

Abstract

This invention relates to a method for controlling the deformation of diaphragm walls, specifically within the field of municipal road foundation pit maintenance technology. It addresses the problem of water leakage at joints caused by unbalanced stress on the inner and outer sides of existing diaphragm walls. The steps are as follows: After the diaphragm wall construction is completed, a correction device is installed at the location of the flexible water-stop joint between adjacent diaphragm walls, with the width of the correction device being greater than the width of the flexible water-stop joint.

Description

Technical Field

[0001] This invention relates to the field of municipal road foundation pit maintenance technology, and in particular to a method for controlling the deformation of underground continuous walls. Background Technology

[0002] Currently, diaphragm walls are typically constructed using a segmented cast-in-place method, with flexible water-stop joints often connecting each segment. However, due to inconsistent soil and water pressure on the outer side and stress on the inner supporting structure of each diaphragm wall, and because the flexible water-stop joints have relatively low stiffness compared to the diaphragm wall itself, the imbalance of forces on the inner and outer sides of the diaphragm wall can lead to significant relative displacement between adjacent walls. Furthermore, the flexible water-stop joints are susceptible to tensile stress and damage, resulting in water leakage at the joints. Summary of the Invention

[0003] To address the problem of water leakage at joints caused by unbalanced stress on the inner and outer sides of existing diaphragm walls, the present invention aims to provide a method for controlling the deformation of diaphragm walls.

[0004] The technical solution adopted by this invention to solve its technical problem is: a method for controlling the deformation of underground diaphragm walls, the steps of which are as follows:

[0005] After the diaphragm wall construction is completed, a correction device is installed at the location of the flexible water-stop joint between adjacent diaphragm walls, and the width of the correction device is greater than the width of the flexible water-stop joint.

[0006] The deformation control method for diaphragm walls in this embodiment involves setting up a correction device at the flexible water-stop joint of adjacent diaphragm walls. The water and soil pressure at the flexible water-stop joint first acts on the correction device, which redistributes the water and soil pressure and then transmits it to the diaphragm walls on both sides, gradually reducing the relative displacement between the two adjacent diaphragm walls. This effectively corrects the relative displacement between the adjacent diaphragm walls, thereby simply and efficiently reducing the relative deformation between the adjacent diaphragm walls. Furthermore, it reduces the tensile stress on the flexible water-stop joint, lowering the subsequent construction risks caused by water leakage from the diaphragm walls after the foundation pit excavation.

[0007] Furthermore, the correction device is a strip steel plate, which is vertically arranged on the outside of the flexible waterstop joint, and the width of the strip steel plate is greater than the width of the flexible waterstop joint.

[0008] Furthermore, the correction device is a steel pipe, which is vertically installed on the outside of the flexible water-stop joint, and the outer diameter of the steel pipe is larger than the width of the flexible water-stop joint.

[0009] Furthermore, the correction device includes a T-shaped screw, a washer, and a nut. The width of the flange of the T-shaped screw and the width of the washer are both greater than the width of the flexible water-stop joint. The T-shaped screw is vertically driven into the outside of the diaphragm wall from the crack generated by the tensile failure of the flexible water-stop joint. The washer is vertically inserted into the inside of the flexible water-stop joint. Then, the flange of the T-shaped screw is rotated to a horizontal state. The other end of the T-shaped screw passes through the flexible water-stop joint and is sleeved and connected with the washer. The end of the screw is locked and fixed by a nut. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the water and soil pressure at the joint of adjacent underground continuous walls in Embodiment 1 of the present invention;

[0011] Figure 2 This is a schematic diagram showing water leakage at the flexible water-stop joint between adjacent underground continuous walls in Embodiment 1 of the present invention;

[0012] Figure 3 This is a schematic diagram of the structure in Embodiment 1 of the present invention, in which a steel plate is installed on the outside of the flexible waterstop joint;

[0013] Figure 4 This is a schematic diagram showing the corrected relative displacement between two adjacent diaphragm walls in Embodiment 1 of the present invention;

[0014] Figure 5 This is a schematic diagram of the water and soil pressure at the joint of adjacent underground continuous walls in Embodiment 2 of the present invention;

[0015] Figure 6 This is a schematic diagram showing water leakage at the flexible water-stop joint between adjacent underground continuous walls in Embodiment 2 of the present invention;

[0016] Figure 7 This is a schematic diagram of the structure of a steel pipe installed on the outside of the flexible waterstop joint in Embodiment 2 of the present invention;

[0017] Figure 8 This is a schematic diagram showing the corrected relative displacement between two adjacent underground continuous walls in Embodiment 2 of the present invention;

[0018] Figure 9 This is a schematic diagram of the structure of the correction device installed at the flexible water-stop joint in Embodiment 3 of the present invention.

[0019] The numbers in the diagram are as follows:

[0020] 1. Diaphragm wall; 2. Flexible water-stop joint; 3. Leakage prevention device; 5. Steel plate; 6. Steel pipe; 10. Correction device; 11. T-bolt; 12. Washer plate; 14. Nut. Detailed Implementation

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clearly illustrate the embodiments of the present invention. For ease of description, the terms "upper" and "lower" used below are consistent with the upper and lower directions in the drawings, but this should not be construed as a limitation of the technical solution of the present invention.

[0022] Example 1

[0023] like Figure 1 and Figure 2 As shown, the arrow indicates the direction of water and soil pressure on the outside of the diaphragm wall 1. Flexible water-stop joints 2 are used between adjacent diaphragm walls 1. Due to the relatively large deformation between adjacent diaphragm walls 1, water leakage 3 occurs at the joint. The following is combined with... Figure 3 and Figure 4 The deformation control method for diaphragm walls in this embodiment is described in detail below:

[0024] After the construction of the diaphragm wall 1 is completed, a strip steel plate 5 is driven into the outside of the flexible water-stop joint 2 of the adjacent diaphragm wall 1. The strip steel plate 5 is vertically connected to the outside of the flexible water-stop joint 2 (with the direction of the foundation pit as the inside and the direction of the soil as the outside), and the width of the strip steel plate 5 is greater than the width of the flexible water-stop joint 2.

[0025] The deformation control method for diaphragm walls in this embodiment involves inserting a strip steel plate 5 into the outer side of the flexible water-stop joint 2 of adjacent diaphragm walls 1. The water and soil pressure at the flexible water-stop joint 2 is first applied to the steel plate 5, which evenly distributes the water and soil pressure. This pressure is then transmitted to the left diaphragm wall 1 through the steel plate 5, causing the left diaphragm wall 1 to move inward towards the pit. This gradually reduces the relative displacement between the two adjacent diaphragm walls 1, effectively correcting the relative displacement between them. This simple and efficient method reduces the relative deformation between the adjacent diaphragm walls 1. Furthermore, it reduces the tensile stress on the flexible water-stop joint 2, thereby lowering the subsequent construction risks caused by water leakage 3 from the diaphragm wall 1 after pit excavation.

[0026] Example 2

[0027] Unlike Example 1, as Figure 5 and Figure 6 As shown, the width of the flexible waterstop joint 2 between adjacent diaphragm walls 1 is relatively small. The following is combined with... Figure 7 and Figure 8 The deformation control method for diaphragm walls in this embodiment is described in detail below:

[0028] After the construction of the diaphragm wall 1 is completed, steel pipes 6 are driven into the outside of the flexible water-stop joints 2 of the adjacent diaphragm walls 1. The steel pipes 6 are vertically connected to the outside of the flexible water-stop joints 2, and the outer diameter of the steel pipes 6 is greater than the width of the flexible water-stop joints 2.

[0029] In this embodiment, the deformation control method for diaphragm walls involves driving a steel pipe 6 into the outer side of the flexible water-stop joint 2 of adjacent diaphragm walls 1. The water and soil pressure at the flexible water-stop joint 2 is first applied to the steel pipe 6, which is then redistributed through the steel pipe 6 and transmitted to the left diaphragm wall 1. This causes the left diaphragm wall 1 to move inward towards the pit, gradually reducing the relative displacement between the two adjacent diaphragm walls 1. This method effectively and efficiently reduces the relative deformation between adjacent diaphragm walls 1 and corrects the relative displacement between them. Furthermore, by reducing the tensile stress on the flexible water-stop joint 2, the risk of subsequent construction caused by water leakage 3 from the diaphragm wall 1 after pit excavation is reduced. Compared to the steel plate 5 in Embodiment 1, the steel pipe 6 has the advantages of deeper embedment and greater rigidity.

[0030] Example 3

[0031] Unlike Examples 1 and 2, in combination Figure 9 The deformation control method for diaphragm walls in this embodiment is described in detail below:

[0032] After the construction of the diaphragm wall 1 is completed, a correction device 10 is installed at the flexible water-stop joint 2 of the adjacent diaphragm wall 1. The correction device 10 includes a T-shaped screw 11, a pad 12, and a nut 14. The width of the flange of the T-shaped screw 11 and the width of the pad 12 are both greater than the width of the flexible water-stop joint 2. During correction, the T-shaped screw 11 is vertically driven into the outside of the diaphragm wall 1 from the crack generated by the tensile failure of the flexible water-stop joint 2 (or the crack can be artificially generated by drilling). The pad 12 is vertically inserted into the inside of the flexible water-stop joint 2. The pad 12 has a through hole (not shown in the figure) that is adapted to the rod body of the T-shaped screw 11. Then, the flange of the T-shaped screw is rotated 90 degrees to make it horizontal. The rod body of the T-shaped screw passes through the flexible water-stop joint 2 and the through hole of the pad 12, and the exposed end of the T-shaped screw is tightened and fixed by the nut 14.

[0033] The deformation control method for diaphragm walls in this embodiment involves installing a correction device 10 at the flexible water-stop joint 2 of adjacent diaphragm walls 1. The T-shaped screw of the correction device 10 passes through the flexible water-stop joint 2 between adjacent diaphragm walls 1. The flange of the T-shaped screw is snapped onto the outside of the flexible water-stop joint 2. The pad 12 inserted into the inside of the flexible water-stop joint 2 is sleeved on the end of the screw and locked by a nut 14. Due to the extremely high weight of the diaphragm wall 1, even after one end of the T-shaped screw is snapped onto the flexible water-stop joint 2 and the other end is locked by the nut 14, there may still be a certain displacement difference between the two adjacent diaphragm walls 1. Under the action of the correction device 10, the relative displacement between the adjacent diaphragm walls 1 will not continue to increase, but will only decrease with the subsequent water and soil pressure. This effectively suppresses the relative displacement between the adjacent diaphragm walls 1, thereby simply and efficiently reducing the relative deformation between the adjacent diaphragm walls 1. Moreover, by reducing the tensile stress on the flexible water-stop joint 2, the risk of subsequent construction caused by water leakage 3 of the diaphragm wall 1 after the excavation of the foundation pit is reduced.

[0034] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the scope of the claims.

Claims

1. A method for controlling the deformation of a diaphragm wall, characterized in that, The steps are as follows: After the diaphragm wall construction is completed, a correction device is installed at the location of the flexible water-stop joint between adjacent diaphragm walls, and the width of the correction device is greater than the width of the flexible water-stop joint. The correction device includes a T-shaped screw, a washer, and a nut. The width of the flange of the T-shaped screw and the width of the washer are both greater than the width of the flexible water-stop joint. The T-shaped screw is vertically driven into the outside of the diaphragm wall from the crack generated by the tensile failure of the flexible water-stop joint. The washer is vertically inserted into the inside of the flexible water-stop joint. Then, the flange of the T-shaped screw is rotated to a horizontal state. The other end of the T-shaped screw passes through the flexible water-stop joint and is sleeved and connected to the washer. The end of the screw is locked and fixed by a nut.

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