Waterproof structure at interface between temporary lattice column and bottom plate of foundation pit
Patent Information
- Application Number
- CN202610997836.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-06
- Publication Date
- 2026-08-07
AI Technical Summary
[0006]针对现有技术中，格构柱与底板接口处防水措施单一、缺乏系统层次设计、防水可靠性不足的问题，开创性地将后浇带超前止水思路应用到格构柱与底板接口的防水构造，提供一种从底部至上部多层次防水体系的基坑临时格构柱与底板接口处防水结构
（1）多道设防，防水可靠性高。本发明自下而上设置了底部防水层+密封胶→内外止水钢板+遇水膨胀止水条→钢板止水带→后浇膨胀混凝土→预埋注浆管等多道防水措施，形成“以防为主、多道设防、注浆补救”的完整防水体系。显著提高了格构柱与底板接口处的防水可靠性，即使某一道防水措施因施工缺陷或材料老化失效，后续防水措施仍能发挥作用，并为后期维护提供了注浆补救条件，具有良好的应用效果和推广价值，显著提高了防水可靠性。
Smart Images
Figure CN122522745A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of waterproofing construction technology in building engineering. Specifically, it relates to a waterproofing structure at the interface between a temporary lattice column and the foundation slab in a foundation pit, particularly suitable for waterproofing the portion of the temporary lattice column penetrating the foundation slab in deep foundation pit projects. Background Technology
[0002] In deep foundation pit construction, temporary lattice columns are often installed as vertical load-bearing components of the horizontal support system to meet the needs of foundation pit support. These lattice columns must penetrate the foundation slab and can only be removed after the foundation pit is backfilled. However, the part where the lattice columns penetrate the foundation slab is a weak link in the slab's waterproofing system: on the one hand, the angle steel and gusset plates of the lattice columns obstruct the passage of the slab's reinforcing steel bars, easily leading to the cutting off of the steel bars and affecting the structural performance of the slab; on the other hand, the "vertical joint" formed at the interface between the concrete and the steel column is a weak point in the self-waterproofing of the slab concrete. In addition, the lattice columns penetrating the slab's waterproof membrane prevent it from forming a whole, thus affecting the slab's waterproofing performance. In actual construction, the quality of waterproofing construction at the intersection of the lattice columns and the slab is difficult to guarantee, and water seepage and leakage often occur after construction.
[0003] Currently, for waterproofing issues at the penetration points of lattice columns into the base slab, existing technologies primarily address waterproofing by welding steel rings to the lattice column, supplemented by measures such as water-swellable waterstop strips and waterproof sealant. For example, one existing technology discloses a scheme involving installing a waterstop steel plate, a barrier steel plate, a water-swellable waterstop strip, and a cement-based penetrating crystalline waterproof coating layer at the penetration point of the lattice column. Another technology addresses this by laying waterproof membrane on the base slab cushion layer, applying waterproof sealant at the junction of the lattice column and the waterproof membrane, and attaching a water-swellable waterstop strip to the outside of the lattice column. Yet another existing technology employs a basin-type waterstop steel plate welded and fixed to the perimeter of a temporary lattice column, facilitating the compaction of the concrete beneath the base slab and reducing the gap between the waterstop steel plate and the underlying concrete.
[0004] However, the existing technical solutions mentioned above have the following shortcomings: First, the waterproofing measures are relatively simple, and it is difficult to form a multi-layered defense system by relying solely on water-stop steel plates and water-stop strips. Once a certain link fails, the overall waterproofing function is lost. Second, there is a lack of systematic waterproofing structural design for the vertical layers from the bottom waterproofing layer to the upper concrete at the interface between the lattice column and the base plate. Third, the mature practice of the advanced water-stop node of the post-pouring strip has not been fully adopted and applied to the interface of the lattice column to form a systematic waterproof protection.
[0005] The core idea of "advanced waterproofing" for post-cast strips is to pre-install an independent, permanent waterproof structure under the base slab while pouring the concrete on both sides of the post-cast strip, which has been proven to be effective in waterproofing. However, there is currently no publicly available technical solution for applying the systematic, layered waterproofing concept of advanced waterproofing of post-cast strips to the interface between temporary lattice columns and the base slab. Summary of the Invention
[0006] To address the issues of existing technologies, such as the lack of a systematic and hierarchical design and insufficient waterproofing reliability at the interface between lattice columns and the base slab, this paper innovatively applies the concept of pre-sealing with post-cast strips to the waterproofing structure of the interface between lattice columns and the base slab, providing a multi-layered waterproofing system from bottom to top for the temporary lattice column and base slab interface in the foundation pit.
[0007] To achieve the above objectives, the technical solution provided by this invention is as follows: A waterproof structure at the interface between a temporary lattice column and the base slab in a foundation pit includes: a bottom waterproof layer, a fine stone concrete protective layer, a pre-cast concrete base slab, an inner water-stop steel plate and an outer water-stop steel plate, a steel plate water-stop strip, post-cast expansive concrete, and a grouting pipe. The bottom waterproof layer is set on the concrete pad, and sealant is provided at the intersection of the bottom waterproof layer and the lattice column; The fine aggregate concrete protective layer is set on the bottom waterproof layer; The pre-cast concrete base slab is set on the fine stone concrete protective layer, and a post-cast strip area is reserved around the lattice column; At the intersection of the first-poured concrete base slab and the lattice column, the inner water-stop steel plate and the outer water-stop steel plate are respectively installed on the inner and outer sides of the lattice column. Water-swellable water-stop strips are provided at the intersection of the inner water-stop steel plate and the outer water-stop steel plate with the lattice column. The post-cast expansive concrete is used to fill the post-cast strip area around the lattice column; The steel plate waterstop is installed at the junction of the post-cast expansive concrete and the pre-cast concrete base plate. The steel plate waterstop extends along the junction and is embedded in the post-cast expansive concrete and pre-cast concrete base plates located on both sides of the junction. The grouting pipe is pre-embedded at the edge of the post-cast strip, with the lower end of the grouting pipe extending to the lower part of the tongue and groove of the post-cast expansive concrete or to the side wall, and the upper end of the pre-embedded grouting pipe extending above the top surface of the post-cast expansive concrete.
[0008] The preferred technical solution is that the middle part of the steel plate waterstop is located at the center of the interface between the pre-cast concrete base plate and the post-cast expansive concrete, with half of the steel plate waterstop embedded in the pre-cast concrete base plate and the other half embedded in the post-cast expansive concrete.
[0009] A further preferred technical solution is that the interface between the pre-cast concrete base slab and the post-cast expansive concrete is set as a tongue-and-groove structure, and the steel plate waterstop is located in the middle of the tongue-and-groove structure.
[0010] This further optimized scheme can increase the length of the seepage path.
[0011] A further preferred technical solution is that the steel plate waterstop is a galvanized steel plate waterstop with a width of not less than 200mm and a thickness of not less than 3mm, and is arranged along the entire length of the interface.
[0012] A further improved technical solution includes: a cement-based penetrating crystalline waterproof coating layer; the cement-based penetrating crystalline waterproof coating layer is disposed inside the lattice column, and the cement-based penetrating crystalline waterproof coating layer is applied from the upper surface of the post-cast expansive concrete to the elevation of the inner waterstop steel plate.
[0013] Adding a cement-based penetrating crystalline waterproof coating layer inside the lattice column further enhances its waterproofing effect.
[0014] A further preferred technical solution is that the inner and outer water-stop steel plates are annular steel plates, which are fully welded together along the inner and outer circumferences of the lattice column, respectively; the inner and outer water-stop steel plates are arranged parallel to each other at the middle position of the thickness of the pre-cast concrete base plate, and the vertical distance between the inner and outer water-stop steel plates is not less than 100mm.
[0015] A further preferred technical solution is that the circumferential weld of the outer waterstop steel plate and the circumferential weld of the inner waterstop steel plate are staggered in the circumferential direction of the pile body, and the staggered angle is not less than 30°.
[0016] This preferred solution can prevent weak points in the weld from being on the same vertical line.
[0017] A further preferred technical solution is that the outer waterstop steel plate is welded to the contact point between the reinforcing steel bars of the pre-cast concrete base slab and the lattice column.
[0018] When the outer waterstop steel plate is welded to the contact point between the reinforcing steel of the pre-cast concrete base slab and the lattice column, the outer waterstop steel plate can also serve as a force transmission steel plate, which not only enhances the waterproof effect but also solves the structural stress problem caused by the lattice column cutting off the base slab reinforcing steel, thus achieving multiple uses for one plate.
[0019] A further preferred technical solution is that the bottom waterproof layer is a waterproof membrane, which is turned up at the penetration point of the lattice column and bonded to the side wall of the lattice column with the sealant; the sealant is polyurethane sealant or silicone sealant.
[0020] A more preferred technical solution is that there are multiple grouting pipes, which are arranged at intervals along the edge of the post-cast strip, with a spacing of 0.3 to 0.5 m between adjacent grouting pipes.
[0021] This invention innovatively applies the concept of pre-sealing with post-cast strips to the waterproofing structure of the interface between the lattice column and the base slab. Compared with the prior art, the waterproofing structure at the interface between the temporary lattice column and the base slab in the foundation pit of this invention has the following beneficial effects: (1) Multiple layers of protection ensure high waterproofing reliability. This invention employs multiple waterproofing measures from bottom to top, including a bottom waterproofing layer + sealant → inner and outer water-stop steel plates + water-swellable water-stop strips → steel plate water-stop belt → post-cast expansive concrete → pre-embedded grouting pipes, forming a complete waterproofing system of "prevention as the main focus, multiple layers of protection, and grouting as a remedy." This significantly improves the waterproofing reliability at the interface between the lattice column and the base plate. Even if one waterproofing measure fails due to construction defects or material aging, subsequent waterproofing measures can still function, providing conditions for grouting remedies for later maintenance. It has good application effects and promotional value, significantly improving waterproofing reliability.
[0022] (2) Drawing on the concept of advanced waterproofing of post-cast strips, this invention has a strong systematic approach. The invention systematically transplants the layered waterproofing concept of advanced waterproofing of post-cast strip nodes to the interface of lattice columns. From the bottom waterproofing layer and sealant sealing, to the inner and outer water-stop steel plates and steel plate water-stop strips in the middle, and then to the upper expansive concrete and grouting system, a complete vertical waterproofing layer is formed.
[0023] (3) Combining internal and external elements for tight water stoppage. By simultaneously installing water-stop steel plates inside and outside the lattice column, two-way water stoppage of the lattice column is achieved. The steel plate water-stop strip is set at the interface between the pre-cast concrete base slab and the post-cast expansive concrete, effectively blocking the water seepage channel at the joint between the old and new concrete, making up for the shortcomings of the existing technology that only considers water stoppage in one direction.
[0024] (4) High feasibility of construction. The waterproof structure at each level adopts mature materials and processes, which facilitates on-site construction and quality control. The pre-embedded grouting pipes provide conditions for later maintenance, enabling active grouting and sealing after leakage occurs, which greatly reduces the cost of later leak sealing. Attached Figure Description
[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0026] Figure 1 This is a vertical cross-sectional schematic diagram of the waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit of the present invention.
[0027] Figure 2 for Figure 1 The schematic diagram of section AA shows the planar arrangement of the lattice column, the water-stop steel plate, and the water-swellable water-stop strip.
[0028] Figure 3 for Figure 1 The BB section diagram is a magnified view of the interface between the post-cast expansive concrete and the pre-cast concrete base slab, showing the location of the steel plate waterstop and grouting pipe.
[0029] Attached reference numerals: 1. Concrete pad; 2. Bottom waterproof layer; 3. Sealant; 4. Fine aggregate concrete protective layer; 5. Pre-cast concrete base slab; 6. Inner waterstop steel plate; 7. Outer waterstop steel plate; 8. Water-swellable waterstop strip; 9. Steel plate waterstop strip; 10. Post-cast expansive concrete; 11. Grouting pipe; 12. Lattice column; 121. Lattice column steel column; 122. Lattice column gusset plate; 13. Cement-based penetrating crystalline waterproof coating layer. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.
[0032] like Figures 1 to 3 As shown, the waterproof structure at the interface between the temporary lattice column and the foundation slab in this embodiment is suitable for waterproofing the joint where the temporary lattice column penetrates the foundation slab in deep foundation pit engineering. The waterproof structure, from bottom to top, includes a bottom waterproof layer 2, a fine aggregate concrete protective layer 4, a pre-cast concrete slab 5, an inner water-stop steel plate 6 and an outer water-stop steel plate 7, a steel plate water-stop strip 9, post-cast expansive concrete 10, and a grouting pipe 11.
[0033] Specifically: The bottom waterproof layer 2 is laid on the concrete pad 1, and sealant 3 is applied at the intersection of the bottom waterproof layer 2 and the lattice column 12. Preferably, the bottom waterproof layer 2 is made of waterproof membrane. At the penetration point of the lattice column 12, the waterproof membrane is turned upwards and bonded to the side wall of the lattice column 12 with sealant 3 to form the first waterproof seal. The sealant 3 is preferably polyurethane sealant or silicone sealant, which has good adhesion and elasticity and can accommodate minor deformations between the lattice column 12 and the waterproof membrane.
[0034] A fine aggregate concrete protective layer 4 is poured on top of the bottom waterproof layer 2. Preferably, the thickness of the fine aggregate concrete protective layer 4 is generally 40-50mm, which is used to protect the bottom waterproof layer 2 from damage during subsequent construction.
[0035] The pre-cast concrete base slab 5 is poured on top of the fine stone concrete protective layer 4. The pre-cast concrete base slab 5 is part of the main structure of the base slab, and a post-cast strip area is reserved around the lattice column 12.
[0036] At the intersection of the first-poured concrete base slab 5 and the lattice column 12, an inner water-stop steel plate 6 and an outer water-stop steel plate 7 are respectively installed on the inner and outer sides of the lattice column 12. Water-swellable water-stop strips 8 are provided at the intersections of the inner and outer water-stop steel plates 6 and 7 with the lattice column 12. These strips expand upon contact with water, filling the tiny gaps between the inner and outer water-stop steel plates 6 and 7 and the lattice column 12, forming a second layer of waterproofing. The inner and outer water-stop steel plates 6 and 7 respectively block the seepage channels on the inner and outer sides of the lattice column 12, forming a double-layered water-stop barrier.
[0037] For the water-swellable sealing strip 8, preferably, a slow-expansion type water-swellable rubber strip is used.
[0038] For the inner water-stop steel plate 6 and the outer water-stop steel plate 7, preferably, both the inner water-stop steel plate 6 and the outer water-stop steel plate 7 are annular steel plates, which are fully welded together along the inner and outer circumference of the lattice column 12, respectively. The inner water-stop steel plate 6 and the outer water-stop steel plate 7 are arranged parallel to each other at the middle position of the thickness of the pre-cast concrete base plate 5, and the vertical distance between the inner water-stop steel plate 6 and the outer water-stop steel plate 7 is not less than 100mm.
[0039] In a further preferred embodiment, the circumferential weld of the outer waterstop steel plate 7 and the circumferential weld of the inner waterstop steel plate 6 are staggered around the pile body, with a staggered angle of not less than 30°, so as to avoid the weak links of the welds being on the same vertical line.
[0040] In a further preferred embodiment, the outer waterstop steel plate 7 is welded to the outside of the lattice column 12 and located at the contact point between the reinforcing steel of the pre-cast concrete base slab 5 and the lattice column 12. This allows the outer waterstop steel plate 7 to also serve as a force-transmitting steel plate. The force-transmitting steel plate and the outer waterstop steel plate 7 are combined into one, which not only solves the force transmission problem after the lattice column cuts off the base slab reinforcing steel, but also enhances the water-stopping effect, achieving a unity of structural stress and waterproofing function.
[0041] Post-cast expansive concrete 10 is used to fill the post-cast strip area around the lattice column 12. Preferably, micro-expansion concrete or shrinkage-compensating concrete is used, with the expansion rate controlled between 0.02% and 0.04%. The micro-expansion properties of the post-cast expansive concrete 10 can compensate for concrete shrinkage, making the interface between the new and old concrete tightly bonded and reducing shrinkage cracks.
[0042] The steel plate waterstop 9 is installed at the junction of the post-cast expansive concrete 10 and the pre-cast concrete base slab 5. The steel plate waterstop 9 extends along the junction and is embedded in the post-cast expansive concrete 10 and the pre-cast concrete base slab 5 on both sides of the junction, forming a third layer of waterproofing.
[0043] Preferably, the steel plate waterstop 9 is a galvanized steel plate waterstop with a width of not less than 200mm and a thickness of not less than 3mm, and is arranged along the entire length of the interface. The middle part of the steel plate waterstop 9 is located at the center of the interface between the pre-cast concrete base slab 5 and the post-cast expansive concrete 10, with half of it embedded in the pre-cast concrete base slab 5 and the other half embedded in the post-cast expansive concrete 10.
[0044] For the structure of the interface between the pre-cast concrete base slab 5 and the post-cast expansive concrete 10, preferably, the interface between the pre-cast concrete base slab 5 and the post-cast expansive concrete 10 is set as a tongue and groove structure, and the steel plate waterstop 9 is set in the middle of the tongue and groove structure to increase the length of the seepage path.
[0045] Multiple grouting pipes 11 are arranged circumferentially around the perimeter of the post-cast expansive concrete 10 and pre-embedded at the edge of the post-cast strip. The lower end of the grouting pipe 11 extends to the lower part of the tongue and groove joint or the side wall of the post-cast expansive concrete 10, and the upper end of the pre-embedded grouting pipe 11 extends above the top surface of the post-cast expansive concrete 10, serving as grouting ports. Preferably, the grouting pipes 11 are arranged at intervals along the edge of the post-cast strip, with a spacing of 0.3 to 0.5 meters between adjacent grouting pipes 11. After the post-cast expansive concrete 10 is poured, if leakage occurs at the interface between the old and new concrete, grouting material can be injected through the grouting pipes 11 to seal it, thereby achieving a "maintainable and remediable" waterproof design.
[0046] Furthermore, it also includes a cement-based penetrating crystalline waterproof coating layer 13. The cement-based penetrating crystalline waterproof coating layer 13 is applied inside the lattice column 12, extending from the upper surface of the post-cast expansive concrete 10 along the inner wall of the lattice column 12 to the elevation of the inner waterstop steel plate 6. Its penetrating and crystalline properties further densify the concrete interface inside the lattice column 12, providing auxiliary waterproofing.
[0047] The construction steps for this waterproof structure are as follows: Step S1: Lay the bottom waterproof layer 2 on the concrete pad 1, flip the waterproof membrane upward at the penetration part of the lattice column 12, and use sealant 3 to bond and seal the waterproof membrane to the side wall of the lattice column 12. Step S2: Pour a fine stone concrete protective layer 4 on the bottom waterproof layer 2; Step S3: Apply a cement-based penetrating crystalline waterproof coating layer 13 to the inside of the lattice column 12; Step S4: Weld the inner waterstop steel plate 6 and the outer waterstop steel plate 7 at the same horizontal height inside and outside the lattice column 12 respectively. The outer waterstop steel plate 7 is welded to the contact point between the reinforcing steel of the pre-cast concrete base slab 5 and the lattice column 12, so that the outer waterstop steel plate 7 can also serve as a force transmission steel plate. Install water-swellable waterstop strips 8 at the contact surfaces between the inner waterstop steel plate 6, the outer waterstop steel plate 7 and the lattice column 12. Step S5: Pre-install a steel plate waterstop 9 at the junction of the pre-cast concrete base slab 5 and the post-cast strip area, with half of the steel plate waterstop 9 embedded in the pre-cast concrete base slab 5. Step S6: Tie the reinforcing bars of the pre-cast concrete base slab 5, wherein the outer waterstop steel plate 7, which also serves as a force transmission steel plate, is welded or lapped to the reinforcing bars of the pre-cast concrete base slab 5 to ensure the continuity of structural stress. Step S7: Pour the pre-cast concrete base slab 5, reserve the post-cast strip area around the lattice column 12, and at the same time, pre-embed the grouting pipe 11 at the edge of the post-cast strip. The lower end of the grouting pipe 11 extends to the lower part of the tongue and groove of the post-cast expansive concrete 10 or the side wall. Step S8: After the pre-cast concrete base slab 5 reaches the design strength, pour the post-cast expansive concrete 10 in the post-cast strip area; Step S9: After the post-poured expansive concrete 10 has cured, check the waterproofing effect at the bottom slab interface. If there is leakage, inject grouting material through the pre-embedded grouting pipe 11 for later sealing.
[0048] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
[0049] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.
[0050] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0051] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.
Claims
1. A waterproof structure at the interface between a temporary lattice column and the base slab in a foundation pit, characterized in that, include: Bottom waterproof layer (2), fine stone concrete protective layer (4), pre-cast concrete base slab (5), inner water-stop steel plate (6) and outer water-stop steel plate (7), steel plate water-stop strip (9), post-cast expansive concrete (10) and grouting pipe (11). The bottom waterproof layer (2) is set on the concrete cushion layer (1), and a sealant (3) is set at the intersection of the bottom waterproof layer (2) and the lattice column (12). The fine stone concrete protective layer (4) is set on the bottom waterproof layer (2); The pre-cast concrete base plate (5) is set on the fine stone concrete protective layer (4), and a post-cast strip area is reserved around the lattice column (12); At the intersection of the first concrete base slab (5) and the lattice column (12), the inner water-stop steel plate (6) and the outer water-stop steel plate (7) are respectively installed on the inner and outer sides of the lattice column (12). Water-swellable water-stop strips (8) are provided at the intersection of the inner water-stop steel plate (6), the outer water-stop steel plate (7) and the lattice column (12). The post-cast expansive concrete (10) is filled in the post-cast strip area around the lattice column (12); The steel plate waterstop (9) is set at the junction of the post-cast expansive concrete (10) and the pre-cast concrete base plate (5). The steel plate waterstop (9) extends along the junction and is embedded in the post-cast expansive concrete (10) and the pre-cast concrete base plate (5) located on both sides of the junction. The grouting pipe (11) is embedded in the edge of the post-cast strip. The lower end of the grouting pipe (11) extends to the lower part of the tongue and groove of the post-cast expansive concrete (10) or the side wall. The upper end of the embedded grouting pipe (11) extends above the top surface of the post-cast expansive concrete (10).
2. The waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit as described in claim 1, characterized in that, The middle part of the steel plate waterstop (9) is located at the center of the interface between the pre-cast concrete base plate (5) and the post-cast expansive concrete (10). Half of the steel plate waterstop (9) is embedded in the pre-cast concrete base plate (5), and the other half is embedded in the post-cast expansive concrete (10).
3. The waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit as described in claim 2, characterized in that, The interface between the pre-cast concrete base plate (5) and the post-cast expansive concrete (10) is set as a tongue and groove structure, and the steel plate waterstop (9) is set in the middle of the tongue and groove structure.
4. The waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit as described in claim 3, characterized in that, The steel plate waterstop (9) is a galvanized steel plate waterstop with a width of not less than 200mm and a thickness of not less than 3mm, and is arranged along the entire length of the interface.
5. The waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit as described in any one of claims 1 to 4, characterized in that, Also includes: Cement-based penetrating crystalline waterproof coating layer (13); The cement-based penetrating crystalline waterproof coating layer (13) is set inside the lattice column (12), and the cement-based penetrating crystalline waterproof coating layer (13) is brushed from the upper surface of the post-cast expansive concrete (10) to the elevation of the inner waterstop steel plate (6).
6. The waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit as described in claim 5, characterized in that, The inner water-stop steel plate (6) and the outer water-stop steel plate (7) are ring-shaped steel plates, which are fully welded together along the inner and outer circumference of the lattice column (12), respectively. The inner water-stop steel plate (6) and the outer water-stop steel plate (7) are arranged parallel to each other at the middle position of the thickness of the pre-cast concrete base plate (5), and the vertical distance between the inner water-stop steel plate (6) and the outer water-stop steel plate (7) is not less than 100mm.
7. The waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit as described in claim 6, characterized in that, The circumferential weld of the outer waterstop steel plate (7) and the circumferential weld of the inner waterstop steel plate (6) are staggered in the circumferential direction of the pile body, and the staggered angle is not less than 30°.
8. The waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit as described in claim 7, characterized in that, The outer waterstop steel plate (7) is welded to the contact point between the reinforcing steel of the pre-cast concrete base plate (5) and the lattice column (12).
9. The waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit as described in claim 1, characterized in that, The bottom waterproof layer (2) is a waterproof membrane. The waterproof membrane is turned up at the penetration part of the lattice column (12) and bonded and sealed with the side wall of the lattice column (12) by the sealant (3). The sealant (3) is a polyurethane sealant or a silicone sealant.
10. The waterproof structure at the interface between the temporary lattice column and the bottom slab in the foundation pit as described in claim 1, characterized in that, The grouting pipes (11) are multiple and are arranged at intervals along the edge of the post-cast strip, with the spacing between adjacent grouting pipes (11) being 0.3 to 0.5 m.