Reinforcement structure at the joint between the ground wall and the enclosure and construction method of the reinforcement structure

Abstract

The present application provides a reinforcement structure and a construction method of the reinforcement structure at the joint between the diaphragm wall and the retaining structure, which relates to the technical field of building construction. The reinforcement structure at the joint between the diaphragm wall and the retaining structure includes a diaphragm wall, a retaining structure, a first reinforcement member, and a second reinforcement member. The retaining structure includes a bored cast-in-place pile and a waterproof curtain. The bored cast-in-place pile is connected to the diaphragm wall, and a first reinforcement member is provided on the outer side of the joint. The waterproof curtain is located on the outer side of the bored cast-in-place pile. A plurality of first triangular parts are formed between the bored cast-in-place pile and the waterproof curtain, and a second reinforcement member is provided at a part of the plurality of first triangular parts close to the joint. The reinforcement structure at the joint between the diaphragm wall and the retaining structure can prevent water leakage and eliminate water leakage accidents. Even if a danger of foundation pit water leakage occurs, the occurrence of leakage and the possibility of leakage expansion can be effectively avoided, the difficulty of plugging is greatly reduced, and the safety risk of foundation pit construction is reduced. Therefore, a large amount of plugging treatment costs can be saved, and good economic and social benefits are achieved.

Description

Technical Field

[0001] This application relates to the technical field of building construction, and more particularly, to a reinforcement structure at the joint between a diaphragm wall and a retaining structure and a construction method of the reinforcement structure. Background Art

[0002] The combined retaining structure of diaphragm walls, cast-in-place bored piles and cut-off walls is used in foundation pit projects such as urban subways and building construction. Diaphragm walls (referred to as "diaphragm walls" for short) have the characteristics of water interception, seepage prevention, and load-bearing. However, due to the technological characteristics of cast-in-place bored piles (non-interlocking piles) not having functions such as water interception and seepage prevention, when cast-in-place bored piles are selected as the retaining structure, a cut-off wall needs to be constructed additionally on the outside. Usually, the construction process is to construct jet grouting piles outside the cast-in-place bored piles as the cut-off wall to achieve the water-stopping effect.

[0003] Under certain specific poor geological conditions such as fine silt sand layer geology and excessive reinforcement depth, the pile-forming effect of high-pressure jet grouting piles is not ideal, and their theoretical pile diameters cannot be guaranteed. The jet grouting piles do not interlock with each other, and the overlap is insufficient, resulting in the formation of seepage channels inside the jet grouting pile cut-off wall reinforcement, thus causing seepage and leakage accidents. Summary of the Invention

[0004] An object of this application is to provide a reinforcement structure at the joint between a diaphragm wall and a retaining structure, which can improve the problem of water seepage between the diaphragm wall and the retaining structure.

[0005] Another object of this application is to provide a construction method of the reinforcement structure, which can be used to construct the reinforcement structure at the joint between the diaphragm wall and the retaining structure to improve the existing problems.

[0006] The embodiments of this application are implemented as follows:

[0007] The embodiments of this application provide a reinforcement structure at the joint between a diaphragm wall and a retaining structure, including: a diaphragm wall, a retaining structure, a first reinforcement member, and a second reinforcement member;

[0008] The retaining structure includes a cast-in-place bored pile and a cut-off wall. The cast-in-place bored pile is connected to the diaphragm wall, and the first reinforcement member is provided outside the joint. The cut-off wall is located outside the cast-in-place bored pile. A plurality of first triangular parts are formed between the cast-in-place bored pile and the cut-off wall, and the second reinforcement member is provided at a part of the plurality of first triangular parts close to the joint.

[0009] A protection can be formed between the diaphragm wall and the retaining structure, and the first reinforcement member can play a certain role in blocking water. By providing the second reinforcement member at the first triangular parts formed between the cast-in-place bored pile and the cut-off wall, the water leakage can be further prevented, and the seepage and leakage accidents can be eliminated.

[0010] In addition, the reinforcement structure at the joint between the diaphragm wall and the retaining structure provided by the embodiments of the present application may further have the following additional technical features:

[0011] In an alternative embodiment of the present application, both the first reinforcement member and the second reinforcement member are jet grouting piles.

[0012] The technology of jet grouting piles is mature, which can effectively play a reinforcement role at key positions and prevent water leakage.

[0013] In an alternative embodiment of the present application, the second reinforcement members are provided at a plurality of the first triangular portions within 8 meters near the joint.

[0014] Based on experimental comparisons carried out under poor geological conditions and summary of on-site actual construction experience, it is found that when the reinforcement area is 8 meters, the maximum benefit can be obtained by comprehensively considering the probability of leakage and the cost required for reinforcement.

[0015] In an alternative embodiment of the present application, the jet grouting pile serving as the second reinforcement member has a reinforcement point, and the reinforcement point is located outside the center point of the center line connecting two adjacent bored cast-in-place piles.

[0016] Setting the jet grouting pile at this position can ensure the firmness of the jet grouting pile and prevent water leakage.

[0017] In an alternative embodiment of the present application, the reinforcement point is 200 mm away from the center point of the center line connecting two adjacent bored cast-in-place piles.

[0018] Under this spacing, the formed jet grouting pile can have a good biting degree with the cut-off wall, ensuring the water stop effect.

[0019] In an alternative embodiment of the present application, the cut-off wall is a TRD cut-off wall.

[0020] In an alternative embodiment of the present application, a second triangular portion is formed between the joint of the bored cast-in-place pile and the diaphragm wall and the TRD cut-off wall, and the second reinforcement member is provided at the second triangular portion.

[0021] Further setting the second reinforcement member at this position can further prevent water leakage from occurring.

[0022] The embodiments of the present application provide a method for constructing a reinforcement structure, which is used to construct the reinforcement structure at the joint between the diaphragm wall and the retaining structure described in any one of the above, and the method includes:

[0023] After the diaphragm wall and the retaining structure are formed, jet grouting is performed outside the joint between the bored cast-in-place pile and the diaphragm wall to form the first reinforcement member, and jet grouting is performed at the first triangular portion between the pile joint of the bored cast-in-place pile and the cut-off wall to form the second reinforcement member.

[0024] This method can complete the construction of the reinforcement structure at the joint between the diaphragm wall and the retaining structure, making the protection between the underground continuous wall and the retaining structure reliable and avoiding water leakage accidents.

[0025] In an alternative embodiment of the present application, a triple-tube jet grouting pile is used to jet and form the second reinforcement member.

[0026] In an alternative embodiment of the present application, the second reinforcement member and the cut-off wall are overlapped by 100 mm.

[0027] Such an overlapping amount is sufficient to ensure that the first triangular part can be filled densely, playing a role in preventing water leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 Schematic diagram before the first reinforcement member and the second reinforcement member are provided for the underground continuous wall and the retaining structure;

[0030] Figure 2 For Figure 1 Partial enlarged view of part A;

[0031] Figure 3 For Figure 1 Partial enlarged view of part B;

[0032] Figure 4 For Figure 1 Schematic diagram after the second reinforcement member is provided;

[0033] Figure 5 For Figure 4 Partial enlarged view of part C.

[0034] Reference numerals: 10 - underground continuous wall; 21 - bored cast-in-place pile; 22 - cut-off wall; 30 - first reinforcement member; 40 - second reinforcement member; 101 - first triangular part; 102 - second triangular part. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Apparently, the described embodiments are some, but not all, of the embodiments of this application. Components of the embodiments of this application usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0036] Therefore, the detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of this application that is claimed, but merely represents selected embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts fall within the scope of protection of this application.

[0037] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0038] In the description of this application, it should be noted that the orientation or positional relationship indicated by terms such as "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product is usually placed during use. This is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. In addition, terms such as "first", "second", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance.

[0039] In the description of this application, it should also be noted that unless otherwise clearly specified and limited, the terms "arranged", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0040] Embodiment

[0041] Please refer to Figures 1 to 5 , the embodiment of this application provides a reinforcement structure at the joint between the diaphragm wall and the retaining structure, including: a diaphragm wall 10, a retaining structure, a first reinforcement member 30, and a second reinforcement member 40.

[0042] Among them, the enclosure includes bored cast-in-place piles 21 and a water-stop curtain 22. The bored cast-in-place piles 21 are connected to the diaphragm wall 10, and a first reinforcement member 30 is provided on the outer side of the joint. The water-stop curtain 22 is located on the outer side of the bored cast-in-place piles 21. A plurality of first triangular parts 101 are formed between the bored cast-in-place piles 21 and the water-stop curtain 22. A second reinforcement member 40 is provided in the part of the plurality of first triangular parts 101 close to the joint.

[0043] In terms of Figure 1 the perspective, the outer side is the upper side in the figure. It can be understood that the side facing the inside of the foundation pit is the inner side, and the side facing the outside of the foundation pit is the outer side.

[0044] Among them, the first triangular part 101 can be referred to Figure 2 as shown. The second triangular part 102 referred to below can be referred to Figure 3 . It should be understood that the triangular part does not mean that it must be a standard triangle. Generally speaking, if it is generally triangular in shape, it can be regarded as a triangular area.

[0045] In this embodiment, the water-stop curtain 22 is a TRD water-stop curtain, that is, the water-stop curtain 22 constructed by the TRD method (Trench cutting Re-mixing Deep wall method). Its technology is mature and reliable and is suitable for use as an enclosure structure.

[0046] In this embodiment, both the first reinforcement member 30 and the second reinforcement member 40 are jet grouting piles, and the reinforcement depth is the same as the depth of the water-stop curtain 22. The main technical parameters of the jet grouting piles in this embodiment can be referred to the following table:

[0047]

[0048] The jet grouting pile technology is mature and can effectively play a reinforcement role at key positions to prevent water leakage.

[0049] Within the range of 8 meters close to the joint ( Figure 4 the S area part shown in Figure 4 ), a second reinforcement member 40 is provided in each of the plurality of first triangular parts 101. Based on the experimental comparison carried out under poor geological conditions and the summary of on-site actual construction experience, it is found that when the reinforcement area is 8 meters, the maximum benefit can be obtained by comprehensively considering the probability of leakage and the cost required for reinforcement.

[0050] The jet grouting pile serving as the second reinforcement member 40 has reinforcement points, which are located outside the center point of the center line connecting two adjacent bored cast-in-place piles 21. Setting the jet grouting pile at this location can ensure the firmness of the jet grouting pile and prevent water leakage. Optionally, the reinforcement point is 200 mm away from the center point of the center line connecting two adjacent bored cast-in-place piles 21. Under this spacing, the formed jet grouting pile can have a good degree of interlocking with the cut-off wall 22, ensuring the water-stop effect.

[0051] Taking the jet grouting pile with a pile diameter of 800 mm as an example, the effective radius of the jet grouting pile is 400 mm, and the pile diameter of the bored cast-in-place pile 21 is 1000 mm. At this time, the distance between the center line connecting the two bored cast-in-place piles 21 and the TRD cut-off wall is 500 mm. Taking the center point of the center line connecting the two bored cast-in-place piles 21 as an example and offsetting 200 mm outward from the foundation pit, at this time, the jet grouting pile and the TRD cut-off wall interlock by 100 mm. Considering that the diameter of the jet grouting pile is small under adverse conditions, according to this reinforcement plan, this gap can still be closed and filled densely, and generally there is no pile body of the bored cast-in-place pile 21 at this part, and the drilling difficulty of the jet grouting pile is small. If the reinforcement point is offset too far outward from the foundation pit, considering that the diameter of the jet grouting pile is small under adverse conditions, there is a certain possibility that the jet grouting pile and the bored cast-in-place pile 21 cannot interlock, resulting in a seepage channel still existing after reinforcement.

[0052] Please combine Figure 3 and Figure 5 In this embodiment, a second triangular part 102 is formed between the joint of the bored cast-in-place pile 21 and the diaphragm wall 10 and the TRD cut-off wall, and the second triangular part 102 is provided with the second reinforcement member 40. It is found in practice that although there is the first reinforcement member 30 on the outside here, there may still be a possibility of water leakage due to reasons such as the construction environment and geological conditions. Therefore, further setting the second reinforcement member 40 at this location can further avoid the occurrence of water leakage. It can be understood that the second triangular part 102 can also be regarded as the first triangular part 101 between the bored cast-in-place pile 21 and the cut-off wall 22. Since this is an edge position and is close to the diaphragm wall 10, it is slightly different from the complete first triangular part 101, so it is described separately. It should be understood that within 8 meters near the joint, whether it is the first triangular part 101 or the second triangular part 102, a jet grouting pile is provided as the second reinforcement member 40, making it dense and without channels between the bored cast-in-place pile 21 and the cut-off wall 22, preventing the water outside the foundation pit from diffusing to adjacent pile joints through the gap between the bored cast-in-place pile 21 and the cut-off wall 22, effectively avoiding the occurrence of leakage and the possibility of leakage expansion, greatly reducing the difficulty of plugging and reducing the safety risk of foundation pit construction.

[0053] The embodiment of the present application provides a reinforcement structure construction method for constructing a reinforcement structure at the joint of the diaphragm wall and the retaining structure. The method includes:

[0054] After the diaphragm wall 10 and the retaining structure are formed, jet grouting is carried out on the outer side of the joint between the bored cast-in-place pile 21 and the diaphragm wall 10 to form the first reinforcement member 30 (reference can be made to the structure shown in Figure 4 ). Jet grouting is carried out in the first triangular part 101 between the pile joint of the bored cast-in-place pile 21 and the water-stop curtain 22 to form the second reinforcement member 40 (reference can be made to the structure shown in Figure 4 ). Of course, additional second reinforcement members 40 can also be formed by jet grouting in the second triangular part 102 at the same time, as shown in Figure 5 .

[0055] This method can complete the construction of the reinforcement structure at the joint between the diaphragm wall and the retaining structure, making the protection between the diaphragm wall and the retaining structure reliable and avoiding water leakage accidents.

[0056] Among them, a triple-tube jet grouting pile is used to jet grout to form the second reinforcement member 40. Optionally, the second reinforcement member 40 is overlapped with the water-stop curtain 22 by 100 mm. Such an overlapping amount is sufficient to ensure that the first triangular part 101 can be filled densely, playing a role in preventing water leakage.

[0057] To sum up, the reinforcement structure at the joint between the diaphragm wall and the retaining structure of the present application can rely on the diaphragm wall 10 and the retaining structure to form a protection, and the first reinforcement member 30 can play a certain role in blocking water. The second reinforcement member 40 is arranged in the first triangular part 101 formed by the bored cast-in-place pile 21 and the water-stop curtain 22, which can further prevent water leakage and eliminate water leakage accidents. Even if a water leakage risk occurs in the foundation pit due to other reasons, this reinforcement structure can effectively avoid the occurrence of leakage and the possibility of leakage expansion, greatly reducing the difficulty of plugging and reducing the safety risk of foundation pit construction. Thus, a large amount of plugging treatment costs can be saved, and good economic and social benefits are achieved.

[0058] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A reinforcement structure at the joint between a diaphragm wall and a retaining structure, characterized in that, it includes: a diaphragm wall, a retaining structure, a first reinforcement member and a second reinforcement member; The retaining structure includes a bored cast-in-place pile and a water-stop curtain. The bored cast-in-place pile is connected to the diaphragm wall, and the first reinforcement member is provided on the outer side of the joint. The water-stop curtain is located on the outer side of the bored cast-in-place pile. A plurality of first triangular parts are formed between the bored cast-in-place pile and the water-stop curtain, and the second reinforcement member is provided at a part of the plurality of first triangular parts close to the joint; Both the first reinforcement member and the second reinforcement member are jet grouting piles; The second reinforcement member is provided at a plurality of the first triangular parts within 8 meters close to the joint; The water-stop curtain is a TRD water-stop curtain; A second triangular part is formed between the joint of the bored cast-in-place pile and the diaphragm wall and the TRD water-stop curtain, and the second reinforcement member is provided at the second triangular part.

2. The reinforcement structure at the joint between a diaphragm wall and a retaining structure according to claim 1, characterized in that, The jet grouting pile as the second reinforcement member has a reinforcement point, and the reinforcement point is outside the center point of the center line connecting two adjacent bored cast-in-place piles.

3. The reinforcement structure at the joint between a diaphragm wall and a retaining structure according to claim 2, characterized in that, The reinforcement point is 200 mm away from the center point of the center line connecting two adjacent bored cast-in-place piles.

4. A method for constructing a reinforcement structure, which is used to construct the reinforcement structure at the joint between a diaphragm wall and a retaining structure according to any one of claims 1-3, characterized in that, the method includes: After the diaphragm wall and the retaining structure are formed, jet grouting is carried out on the outer side of the joint between the bored cast-in-place pile and the diaphragm wall to form the first reinforcement member, and jet grouting is carried out at the first triangular part between the pile joint of the bored cast-in-place pile and the water-stop curtain to form the second reinforcement member.

5. The method for constructing a reinforcement structure according to claim 4, characterized in that, A triple-tube jet grouting pile is used to jet grout to form the second reinforcement member.

6. The method for constructing a reinforcement structure according to claim 4, characterized in that, The second reinforcement member and the water-stop curtain are overlapped by 100 mm.

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