Underground diaphragm wall joint embedded freezing pipe water stop joint system

Abstract

The utility model discloses an underground diaphragm wall joint embedded freezing pipe water stop connector system which comprises a special-shaped water stop steel plate and an embedded reinforcement cage. The special-shaped water stop steel plate is fixed at the joint of the continuous wall, and the middle part of the special-shaped water stop steel plate is a main body steel plate with an X-shaped section; straight steel plates are arranged on the front side and the rear side of the main steel plate respectively and are perpendicular to the guide wall. L-shaped steel plates are arranged on the left side and the right side of the main steel plate respectively, L-shaped inner angles face the main steel plate, L-shaped edges of the left L-shaped steel plate and the right L-shaped steel plate are opposite, a gap is formed between the L-shaped edges of the left L-shaped steel plate and the right L-shaped steel plate, and groove bodies are formed between the left L-shaped steel plate and the main steel plate and between the right L-shaped steel plate and the main steel plate respectively. Reinforcement cages are arranged inside and outside the tank body, and freezing pipes are arranged in the reinforcement cages in the tank body. The reverse buckling structures are formed at the joints through the special-shaped water stop steel plates, the integrity between the underground diaphragm walls is enhanced, and the water stop effect is remarkably improved.

Description

Technical Field

[0001] This application relates to the technical field of diaphragm walls, and specifically relates to a pre-buried freezing pipe water-stop joint system for diaphragm wall joints. Background Art

[0002] In recent years, with the development of urban subway construction and underground tunnels, diaphragm walls have been widely used as retaining structures in deep and large foundation pit projects under complex environmental conditions and with high requirements for main body deformation. The joints between diaphragm wall panels are the weak links in the waterproofing of the entire retaining structure. Leakage of the diaphragm wall can lead to a reduction in the strength of the local wall and a decrease in the lateral stiffness, further causing soil erosion outside the pit, manifested as an increase in the lateral displacement of the diaphragm wall and a settlement of the ground behind the pit, seriously affecting the safety of foundation pit construction and the ground environment. In summary, leakage at the joints of the diaphragm wall will seriously affect construction safety.

[0003] Currently, the mainstream methods for preventing leakage at the joints are to stop water from the joint structure before construction or to stop water after water seepage occurs during the construction process. Many joint forms have been innovated in stopping water from the joint structure before construction, such as pipe joints, rubber water-stop joints, etc., but the water-stop effect cannot be guaranteed. Conventional disposal measures for leakage of the existing diaphragm wall joints include hole drilling and grouting reinforcement and plugging behind the diaphragm wall joints, drilling and injecting polyurethane AB liquid for plugging at the joints, and soil grouting reinforcement behind the diaphragm wall joints. Conventional stratum grouting and plugging measures will cause a certain degree of disturbance to the stratum behind the wall joints. The slurry solidifies and expands, increasing the active earth pressure behind the diaphragm wall, which has an impact on the safety of the current foundation pit. At the same time, due to the uncertainty of the slurry flow in the soil, the grouting reinforcement effect behind the wall joints will surely be greatly reduced; in deep foundation pit projects under complex environmental conditions, if the leakage area is close to traffic roads and important buildings, the effectiveness of dealing with the leakage of the diaphragm wall joints is particularly important. In order to reduce the impact on the surrounding environment and the deep foundation pit project itself, reliable and effective plugging measures must be taken to quickly complete the leakage plugging work of the diaphragm wall. Summary of the Utility Model

[0004] The purpose of this application is to provide a pre-buried freezing pipe water-stop joint system for diaphragm wall joints to effectively prevent leakage.

[0005] To achieve the above purpose, the technical solution provided by this application is:

[0006] An embedded freezing pipe water-stop joint system for diaphragm wall joints, comprising a special-shaped water-stop steel plate and a steel reinforcement cage; the special-shaped water-stop steel plate is fixed at the diaphragm wall joint, and the middle part of the special-shaped water-stop steel plate is a main steel plate with an X-shaped cross-section; straight steel plates are respectively arranged on the front and rear sides of the main steel plate, and the straight steel plates are perpendicular to the guide wall; L-shaped steel plates are respectively arranged on the left and right sides of the main steel plate, with the L-shaped inner angles facing the main steel plate, the L-shaped edges of the left L-shaped steel plate and the right L-shaped steel plate are opposite to each other and there is a gap between them, and groove bodies are respectively formed between the left and right L-shaped steel plates and the main steel plate; steel reinforcement cages are arranged both inside and outside the groove bodies, and freezing pipes are arranged inside the steel reinforcement cage in the groove body; the periphery of the special-shaped water-stop steel plate is filled with concrete.

[0007] To optimize the above technical solution, the specific measures taken also include:

[0008] One ends of the straight steel plate and the L-shaped steel plate are respectively connected to an X-shaped end of the main steel plate; the straight steel plate and the L-shaped steel plate are perpendicular to each other.

[0009] Furthermore, the front straight steel plate and the rear straight steel plate of the main steel plate are symmetrical, and the left L-shaped steel plate and the right L-shaped steel plate are symmetrical.

[0010] The lower ends of the freezing pipes are connected and grouped through connecting pipes with adjacent freezing pipes.

[0011] As a preferred solution, there are four groups of the freezing pipes, which are respectively arranged at the four inner corners of the groove body.

[0012] Furthermore, the main steel plate, the straight steel plate and the L-shaped steel plate are welded into an integral structure.

[0013] Steel reinforcement cages are respectively arranged between the two straight steel plates on the front side and between the two straight steel plates on the rear side of the main steel plate.

[0014] Compared with the prior art, the beneficial effects of this application are:

[0015] The embedded freezing pipe water-stop joint system for diaphragm wall joints of this application forms a reverse buckling structure at the joint through the special-shaped water-stop steel plate, enhances the integrity between diaphragm walls, and significantly improves the water-stop effect.

[0016] This application uses freezing pipes to replace some longitudinal bars of the steel reinforcement cage. When the structural water-stop fails, liquid nitrogen can be introduced into the freezing pipes embedded at the special-shaped water-stop steel plate to form a freezing water-stop curtain for water-stop, shortening the water-stop time, reducing labor costs, and minimizing the potential risks in diaphragm wall construction. Brief Description of the Drawings

[0017] Figure 1 : Schematic structural diagram of the embedded freezing pipe water-stop joint system for diaphragm wall joints of this application.

[0018] Figure 2 : Schematic diagram of the use of the pre-embedded freezing pipe water stop joint system for the diaphragm wall joint of this application.

[0019] Figure 3 : Schematic sectional view of the use of the pre-embedded freezing pipe water stop joint system for the diaphragm wall joint of this application.

[0020] Figure 4 : Schematic diagram of the area where the steel reinforcement cage is embedded around the freezing pipe.

[0021] In the figure: 1 - liquid nitrogen tank truck, 2 - liquid nitrogen storage tank, 3 - liquid nitrogen distributor, 4 - connecting pipe, 5 - steel reinforcement cage, 6 - special-shaped water stop steel plate, 7 - diaphragm wall, 8 - guide wall, 9 - air outlet, 10 - liquid inlet, 11 - freezing water stop curtain, 12 - freezing pipe, 13 - elbow pipe, 14 - bottom position of the freezing pipe, 15 - area where the steel reinforcement cage is embedded around the freezing pipe, 16 - main steel plate, 17 - straight steel plate, 18 - L-shaped steel plate. Detailed implementation manners

[0022] The above content of this application will be further described in detail below in the form of embodiments. However, it should not be understood that the scope of the above subject matter of this application is limited to the following embodiments. All technologies implemented based on the above content of this application belong to the scope of this application.

[0023] The orientation or positional relationship therein is based on the relationship shown in the drawings, and is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to this application. In this application, the up and down of Figure 1 are the front and rear orientations, and the left and right of Figure 1 are the left and right orientations.

[0024] This application provides a pre-embedded freezing pipe water stop joint system for the diaphragm wall joint. As Figure 1 shown, it includes a special-shaped water stop steel plate 6, a freezing device, a pre-embedded steel reinforcement cage 5 and concrete;

[0025] The special-shaped water stop steel plate 6 is fixed at the diaphragm wall joint. The middle part of the special-shaped water stop steel plate 6 is a main steel plate 16 with an X-shaped cross-section; straight steel plates 17 are provided on the front and rear sides of the main steel plate 16, and the straight steel plates 17 are perpendicular to the guide wall 8; L-shaped steel plates 18 are provided on the left and right sides of the main steel plate 16, with the L-shaped inner angles facing the main steel plate 16. The L-shaped sides of the left L-shaped steel plate 18 and the right L-shaped steel plate 18 are opposite to each other and there is a gap between them. Grooves are respectively formed between the left and right L-shaped steel plates 18 and the main steel plate 16;

[0026] Reinforcement cages 5 are provided both inside and outside the trough body. Inside the reinforcement cage 5 in the trough body, freezing pipes 12 are provided, and the freezing pipes 12 are connected to a refrigeration device.

[0027] The surrounding of the special-shaped water-stop steel plate 6 is filled with concrete, including the gap between the left L-shaped steel plate 18 and the right L-shaped steel plate 18 which is also filled with concrete.

[0028] In some embodiments, the freezing pipes are embedded in the reinforcement cage, and the freezing pipes replace some longitudinal bars of the reinforcement cage.

[0029] One end of the straight steel plate 17 and the L-shaped steel plate 18 are respectively connected to an X-shaped end of the main steel plate 16; the straight steel plate 17 and the L-shaped steel plate 18 are perpendicular to each other.

[0030] The front straight steel plate 17 and the rear straight steel plate 17 of the main steel plate 16 are symmetrical, and the left L-shaped steel plate 18 and the right L-shaped steel plate 18 are symmetrical.

[0031] The freezing pipes 12 are connected to the refrigeration device. The refrigeration device consists of a liquid nitrogen distributor 3, a liquid nitrogen storage tank 2, a liquid nitrogen tank truck 1 and a connecting pipe 4, as Figure 3 shown. The lower ends of the freezing pipes 12 are connected through the connecting pipe 4 to adjacent freezing pipes 12 to form a group. For a group of adjacent freezing pipes 12 connected in communication, the top of one freezing pipe 12 is a liquid inlet 10, which is connected to the refrigeration device to introduce refrigerating liquid (introduce liquid nitrogen), and the top of the other freezing pipe 12 is a gas outlet 9 (vent nitrogen), as Figure 2 shown.

[0032] As a preferred solution, there are four groups of freezing pipes 12, which are respectively arranged at the four inner corners of the trough body.

[0033] In some embodiments, the special-shaped water-stop steel plate 6 is prefabricated in a factory. The factory uses cold-rolled steel plates or hot-rolled steel plates with a thickness greater than 1.5 mm for blanking, then assembles them, and finally continuously welds both sides between the various components to form a special-shaped water-stop steel plate 6 with a forming section length of 10 meters, and transports it to the construction site for on-site welding according to the specific construction depth requirements.

[0034] In some embodiments, the freezing pipes 12 can be made of low-carbon seamless steel pipes; the bottoms of two adjacent low-carbon seamless steel pipes are connected into a passage through a bent pipe 13.

[0035] In some embodiments, the liquid nitrogen distributor 3 is made of austenitic stainless steel. The connecting pipe 4 of the refrigeration device is selected to have a diameter matching the diameter of the embedded freezing pipe 12 so as to control the flow rate of liquid nitrogen flowing into the freezing pipe 12 when introducing liquid nitrogen. The height of the liquid nitrogen storage tank 2 is greater than that of the liquid nitrogen distributor 3. The freezing pipe 12 is connected to the liquid nitrogen distributor 3 through the connecting pipe 4 to form a passage.

[0036] In some embodiments, a steel reinforcement cage 5 is respectively provided between two straight steel plates 17 on the front side of the main body steel plate 16 and between two straight steel plates 17 on the rear side.

[0037] The specific construction steps of this application are as follows:

[0038] (1) Determine the construction position of the diaphragm wall 7 according to the requirements of the construction scope, and then construct the guide wall 8 according to the position of the diaphragm wall 7;

[0039] (2) Determine the joint position according to the specifications and design construction requirements, and use a grooving machine to excavate a steel plate groove for placing the special-shaped water-stop steel plate 6;

[0040] (3) Use a crane to place the welded special-shaped water-stop steel plate 6 into the dug groove; the middle part of the special-shaped water-stop steel plate 6 is a main body steel plate 16 with an X-shaped cross-section; straight steel plates 17 are respectively provided on the front and rear sides of the main body steel plate 16, and the straight steel plates 17 are perpendicular to the guide wall 8; L-shaped steel plates 18 are respectively provided on the left and right sides of the main body steel plate 16, the L-shaped inner angles face the main body steel plate 16, the L-shaped sides of the left L-shaped steel plate 18 and the right L-shaped steel plate 18 are opposite to each other and there is a gap therebetween, and groove bodies are respectively formed between the left and right L-shaped steel plates 18 and the main body steel plate 16;

[0041] (4) Place the steel reinforcement cage 5 around the special-shaped water-stop steel plate 6 and pour concrete into it. Since the poured concrete increases the contact area with the soil and is also in closer contact with the soil after solidification, the frictional force between the special-shaped water-stop steel plate 6 and both sides is increased, avoiding the displacement of the joint when excavating both sides of the special-shaped water-stop steel plate 6 at the same time, and providing construction conditions for the simultaneous construction of multiple groove sections in the next step;

[0042] (5) Carry out the simultaneous construction of multiple groove sections to shorten the construction time. After the groove section excavation is completed, place the matching steel reinforcement cage 5 into each groove section through a crane, and the steel reinforcement cage 5 extends into the special-shaped water-stop steel plate 6. The freezing pipes 12 are arranged at the four corners of the groove bodies respectively formed between the L-shaped steel plates 18 and the main body steel plate 16; pour concrete into the steel reinforcement cage 5 through a conduit. This step is carried out simultaneously for each groove section. When the concrete solidifies and hardens, the previous construction is completed;

[0043] (6) After the construction is completed, the reinforced concrete extends from the gap between the L-shaped steel plates 18 into the special-shaped water-stop steel plate 6, forming a water-stop joint structure that buckles the reinforced concrete on the special-shaped water-stop steel plate 6, avoiding water seepage from the gap structurally, and this structure can greatly enhance the integrity between the diaphragm walls;

[0044] (7) When the structural water stop fails and leakage occurs, the freezing pipes 12 arranged in the special-shaped water stop steel plate 6 are enabled. The liquid nitrogen tank truck 1 can transport liquid nitrogen at -200 °C to the construction site and store it in the liquid nitrogen storage tank 2. Then, it passes through the connecting pipe 4 and the liquid nitrogen distributor 3 and is introduced into the freezing pipes 12 embedded at the joint gap. The liquid nitrogen quickly vaporizes and takes away the surrounding heat, forming a freezing water stop curtain at the gap. The vaporized nitrogen gas is discharged into the atmosphere through the air outlet 9 at about -50 °C to achieve the effect of water stop in a short time.

[0045] The above is only a preferred embodiment of the present application and does not impose any form of limitation on the present application. Any person skilled in the art, without departing from the scope of the technical solution of the present application and based on the technical essence of the present application, any simple modification, equivalent replacement, and improvement made to the above embodiments shall still fall within the protection scope of the technical solution of the present application.

Claims

1. A system of pre-buried freezing pipe water stop joints for underground continuous wall joints, characterized in that: It includes a special-shaped waterstop steel plate and a steel cage; the special-shaped waterstop steel plate is fixed at the joint of the continuous wall, and the middle part of the special-shaped waterstop steel plate is a main steel plate with an X-shaped cross-section; the front and rear sides of the main steel plate are respectively provided with straight steel plates, and the straight steel plates are perpendicular to the guide wall; the left and right sides of the main steel plate are respectively provided with L-shaped steel plates, and the L-shaped inner angles face the main steel plate, the left L-shaped steel plate and the right L-shaped steel plate have L-shaped edges opposite to each other and a gap is provided between them, and the left and right L-shaped steel plates respectively form a trough body with the main steel plate; steel cages are provided inside and outside the trough body, and freezing pipes are provided in the steel cages in the trough body; the special-shaped waterstop steel plate is filled with concrete.

2. The underground continuous wall joint pre-embedded freezing pipe water stop joint system according to claim 1 is characterized by: One end of the straight steel plate and the L-shaped steel plate is respectively connected to an X-shaped end of the main steel plate.

3. The underground continuous wall joint pre-embedded freezing pipe water stop joint system according to claim 1 is characterized by: The straight steel plate and the L-shaped steel plate are perpendicular to each other.

4. The underground continuous wall joint pre-embedded freezing pipe water stop joint system according to claim 1, characterized in that: The front straight steel plate of the main body steel plate is symmetrical with the rear straight steel plate, and the left L-shaped steel plate is symmetrical with the right L-shaped steel plate.

5. The underground continuous wall joint pre-embedded freezing pipe water stop joint system according to claim 1, characterized in that: The lower end of the freezing pipe is connected to the adjacent freezing pipes through a connecting pipe to form a group, and the freezing pipe is connected to a refrigeration device.

6. The underground continuous wall joint pre-embedded freezing pipe water stop joint system according to claim 5, characterized in that: The freezing pipes are in four groups and are arranged at four inner corners of the tank body respectively.

7. The underground continuous wall joint pre-embedded freezing pipe water stop joint system according to claim 1, characterized in that: The main steel plate is welded with the straight steel plate and the L-shaped steel plate to form an integrated structure.

8. The underground continuous wall joint pre-embedded freezing pipe water stop joint system according to claim 1, characterized in that: Steel reinforcement cages are respectively arranged between the two straight steel plates on the front side of the main steel plate and between the two straight steel plates on the rear side.

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