A subway foundation pit dewatering well water stop device
By using a three-layer water-stop steel plate flange assembly in the subway foundation pit drainage well, combined with the design of rubber waterstop and pressure-sealed steel plate, the problems of waterproof membrane not being able to be tightly applied and the construction of welded flanges being complicated were solved, achieving a simple and efficient waterproof effect and ensuring the waterproof quality and construction progress of the subway foundation pit drainage well.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- THE THIRD CONSTR ENG CO LTD OF CHINA CONSTR SECOND ENG BUREAU
- Filing Date
- 2025-06-18
- Publication Date
- 2026-08-04
AI Technical Summary
Existing waterproofing methods for subway foundation pit drainage wells have problems such as the inability to tightly adhere and effectively connect waterproof membranes. Traditional welded flange construction is complex and affects the construction progress, and existing equipment is highly dependent on it, which can easily lead to sealing failure.
A three-layer water-stop steel plate flange assembly is adopted, including a rubber waterstop, a pressure-bonded steel plate, and a waterstop steel plate. The three-layer waterproof system is constructed by bolt connection. The combination of the rubber waterstop and the pressure-bonded steel plate design achieves a tight waterproof effect.
It simplifies construction operations, reduces construction costs, improves waterproofing performance, avoids sealing failures due to equipment malfunctions, and ensures construction progress and quality.
Smart Images
Figure CN224591476U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of subway foundation pit construction technology, specifically to a water-stopping device for a subway foundation pit drainage well. Background Technology
[0002] With the rapid development of subway construction, and the widespread use of in-pit dewatering wells in deep foundation pit construction, these wells, due to their construction characteristics, remain in place throughout the entire subway station structure construction process. This can lead to weaknesses in the waterproofing of the well edges. As subway construction standards continue to rise, waterproofing requirements are becoming increasingly stringent. Furthermore, Beijing's groundwater level has been rising steadily over the past decade. Whether the waterproofing method for the well edges can meet the specifications and design requirements is a crucial construction indicator for the main subway station structure and a key component of dewatering control. Therefore, controlling the construction process of waterproofing the subway foundation pit dewatering wells is extremely important. Effective waterproofing of the well edges, as a key aspect of the subway foundation slab structure construction quality, is a critical technique in subway dewatering.
[0003] There are two traditional construction methods. The first method involves wrapping waterproof membrane around the outside of the drain manhole steel pipe. This method has two drawbacks: firstly, the waterproof membrane cannot adhere tightly to the drain manhole pipe wall; secondly, the waterproof membrane cannot effectively bond and adhere to the concrete, creating a risk of leakage at the vertical concrete joints. The second method involves fabricating single or double flanges along the vertical drain manhole shaft, utilizing the effective bonding between reinforced concrete and the steel structure to achieve double-layer waterproofing. However, this method requires strict quality control and complex construction techniques, necessitating welding to achieve effective water-stopping. Welding affects both construction quality and progress. Therefore, a construction method that ensures waterproofing quality while being easy to operate is needed.
[0004] Chinese patent CN116537238A discloses a method for plugging a drainage well in a water-bearing environment. However, it uses a prefabricated flange, which has poor applicability. The construction steps are complicated, and it requires high construction accuracy and coordination. It is highly dependent on equipment. If the equipment fails or is operated improperly (such as the valve not being fully closed), the plugging may fail. Utility Model Content
[0005] The purpose of this utility model is to provide a water-stopping device for the drainage well of a subway foundation pit, so as to solve the problems mentioned in the background art.
[0006] To achieve the above objectives, this utility model provides a water-stopping device for a subway foundation pit drainage well, comprising: a drainage well shaft, wherein the drainage well shaft is provided with three layers of water-stopping steel plate flange assemblies from bottom to top, each layer of water-stopping steel plate flange assembly comprising: a rubber water-stop strip, the rubber water-stop strip being annular and sleeved on the outside of the drainage well shaft shaft; a pressure-bonded steel plate, the pressure-bonded steel plate being fitted and disposed on the outside of the rubber water-stop strip, the pressure-bonded steel plate being a vertically arranged semi-circular structure; a water-stopping steel plate, the water-stopping steel plate being a horizontally arranged semi-circular structure, and two water-stopping steel plates being joined together to form an annular shape and fixed on the outside of the two pressure-bonded steel plates; and angle steel connecting plates, two sets of angle steel connecting plates being disposed at the splicing position of the two water-stopping steel plates, each set of angle steel connecting plates being fixedly connected by bolts.
[0007] In a preferred embodiment, the intermediate layer water-stop steel plate flange assembly is located in the middle of the station floor concrete structure, and the upper layer water-stop steel plate flange assembly and the lower layer water-stop steel plate flange assembly are respectively located 300mm above and below the intermediate layer water-stop steel plate flange assembly.
[0008] In a preferred embodiment, the three layers of waterstop steel plates are staggered in their splicing positions, and the included angle between the splicing positions of two adjacent layers of waterstop steel plates is 30°.
[0009] In a preferred embodiment, the rubber waterstop is a 10mm thick and 50mm wide annular waterstop strip, which is bonded to the outside of the drainage well shaft with waterproof adhesive within its width range. The pressure plate is a 4mm thick and 40mm wide steel plate, with the upper end of the pressure plate lower than the upper end of the rubber waterstop.
[0010] In a preferred embodiment, the water-stop steel plate is a 4mm thick, 100mm wide semi-circular steel plate, and the water-stop steel plate is welded perpendicularly to the adhesive-bonded steel plate.
[0011] In a preferred embodiment, each set of angle steel connecting plates includes two L-shaped angle steels, which are symmetrically arranged at both ends of two waterstop steel plates. The vertical part of the L-shaped angle steels is provided with multiple bolt holes, and the vertical parts of the two L-shaped angle steels in each set of angle steel connecting plates are attached to each other and fastened by bolts.
[0012] Compared with the prior art, the beneficial effects of this utility model are:
[0013] This utility model, based on the construction characteristics of subway drainage wells, features a three-layer water-stop steel plate flange assembly installed from bottom to top within the well shaft. Each layer includes a rubber waterstop strip, a pressure-bonded steel plate, a waterstop steel plate, and an angle steel connecting plate. By combining the waterstop steel plate with the rubber waterstop strip, the joint between the drainage well and the concrete is effectively waterproofed, creating a three-layer waterproof system that effectively waterproofs the joint. This invention is simple to operate, easy to assemble and disassemble, inexpensive, and uses bolted mechanical fastening, ensuring stability and reliability against loosening. Attached Figure Description
[0014] Figure 1 This is a three-dimensional structural diagram of the water-stopping device for the drainage well of the subway foundation pit according to this utility model.
[0015] Figure 2 This is a schematic diagram of the overall structure of the waterproofing construction of the drainage well according to this utility model;
[0016] Figure 3 This is an elevation view of the water-stopping device for the drainage well of the subway foundation pit according to this utility model;
[0017] Figure 4 This is a top view of the water-stop steel plate flange assembly of this utility model;
[0018] Figure 5 This is a cross-sectional view of the water-stop steel plate flange assembly of this utility model.
[0019] Explanation of reference numerals in the attached figures:
[0020] 1. Drainage well shaft; 11. Water-stop steel plate flange assembly; 2. Rubber waterstop strip; 3. Press-bonded steel plate; 4. Water-stop steel plate; 5. Angle steel connecting plate; 6. Bolt; 7. Station floor concrete structural layer; 8. Station floor concrete waterproof protective layer; 9. Station floor concrete cushion layer. Detailed Implementation
[0021] The technical solutions in the embodiments of this utility model will be clearly and completely described below. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.
[0022] Example 1
[0023] like Figures 1 to 5As shown, the preferred embodiment of the subway foundation pit drainage well water-stopping device of this utility model includes: a drainage well cylinder 1, and a three-layer water-stopping steel plate flange assembly 11 arranged from bottom to top on the drainage well cylinder 1. Each layer of water-stopping steel plate flange assembly 11 includes: a rubber water-stopping strip 2, a pressure-bonded steel plate 3, a water-stopping steel plate 4, and an angle steel connecting plate 5. The rubber water-stopping strip 2 is circular and is sleeved on the outside of the drainage well cylinder 1. The pressure-bonded steel plate 3 is attached to the outside of the rubber water-stopping strip 2. The water-stopping steel plate 4 is horizontally arranged and has a semi-circular structure. The pressure-bonded steel plate 3 is a vertically arranged semi-circular steel plate. The water-stopping steel plate 4 is pre-welded vertically onto the pressure-bonded steel plate 3. The two water-stopping steel plates 4 and the two pressure-bonded steel plates 3 are assembled into a circular flange structure, so that its inner diameter is slightly smaller than the outer diameter of the rubber water-stopping strip 2. Two sets of angle steel connecting plates 5 are fixedly installed at the splicing position of two water-stop steel plates 4. Each set of angle steel connecting plates 5 is fixedly connected by bolts 6. The rubber water-stop strip 2 is squeezed by tightening the bolts 6, and the tightness and compression are 2-4mm to achieve a dense waterproof effect.
[0024] The drainage well shaft 1 is a φ280×4mm thick steel pipe shaft. During the construction of the main structure of the subway station, the drainage well shaft 1 is exposed to the concrete structure layer 7 of the station's bottom slab to ensure continuous dewatering during the construction of the main structure. Three waterproof layers are installed within 1000mm of the concrete structure of the station's bottom slab. The middle layer water-stop steel plate flange assembly is located in the middle of the concrete structure of the station's bottom slab. The upper and lower water-stop steel plate flange assemblies are located 300mm above and below the middle layer water-stop steel plate flange assembly, respectively.
[0025] Furthermore, the three layers of waterstop steel plates 4 are staggered in their splicing positions, and the included angle between the splicing positions of two adjacent layers of waterstop steel plates 4 is 30°.
[0026] In this embodiment, the rubber waterstop 2 is a 10mm thick, 50mm wide annular waterstop strip, which is adhered to the outside of the drainage well shaft 1 within its width using waterproof adhesive. The pressure plate 3 is a 4mm thick, 40mm wide steel plate, with its upper end lower than the upper end of the rubber waterstop 2. The waterstop steel plate 4 is a 4mm thick, 100mm wide semi-circular steel plate, which is welded perpendicularly to the pressure plate 3. Each set of angle steel connecting plates 5 includes two 40mm×40mm×4mm L-shaped angle steels, which are symmetrically arranged on the two end planes of the two waterstop steel plates 4, and are welded using double-sided welds. The vertical part of the L-shaped angle steel has multiple bolt holes, and the vertical parts of the two L-shaped angle steels in each set of angle steel connecting plates 5 are attached to each other and fastened with bolts 6.
[0027] Example 2
[0028] The construction process of this utility model is described below:
[0029] The first step is to place the rubber waterstop 2 on the outside of the drainage well shaft 1, apply waterproof adhesive to the outside, attach the waterproof adhesive strip, and apply adhesive a second time to the edge seam.
[0030] The second step is to vertically weld the waterstop steel plate 4 onto the upper part of the pressure-bonded steel plate 3, and weld the angle steel connecting plate 5 to the end of the waterstop steel plate 4. The two semi-circular waterstop steel plates 4 and the two semi-circular pressure-bonded steel plates 3 are combined to form a circular flange structure, which is then set on the outside of the rubber waterstop 2.
[0031] The third step involves using two sets of angle steel connecting plates 5 and M10 bolts 6 to secure the circular flange structure to the outside of the rubber waterstop 2. Tightening the reinforcing M10 bolts ensures that the outside of the rubber waterstop 2 is compacted by the pressure steel plate 3, reducing the compression by 2-4mm, thereby firmly pressing the overall waterstop steel plate flange assembly 11 against the drainage well shaft 1.
[0032] Fourth step, repeat the above steps, install three layers of water-stop steel plate flange assembly within 1000mm of the concrete structure of the station floor slab, the splicing positions of the three layers of water-stop steel plates 4 are staggered, and the included angle between the splicing positions of two adjacent layers of water-stop steel plates 4 is 30°.
[0033] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A subway foundation pit dewatering well water stop device, characterized in that: include: The drainage well shaft (1) is provided with three layers of water-stop steel plate flange assemblies from bottom to top. Each layer of water-stop steel plate flange assembly includes: Rubber waterstop (2), the rubber waterstop (2) is annular, and the rubber waterstop (2) is sleeved on the outside of the well barrel (1) of the drainage well; The adhesive-bonded steel plate (3) is attached to the outside of the rubber waterstop (2). The adhesive-bonded steel plate (3) is a vertically arranged semi-circular structure. Water-stop steel plate (4), the water-stop steel plate (4) is a horizontally set semi-circular ring structure, and two water-stop steel plates (4) are spliced into a ring shape and fixed on the outside of two pressure-bonded steel plates (3); Angle steel connecting plate (5), two sets of the angle steel connecting plates (5) are set at the splicing position of two water-stop steel plates (4), and each set of angle steel connecting plates (5) is fixedly connected by bolts (6).
2. The subway foundation pit dewatering well water stop device according to claim 1, characterized in that: The intermediate layer water-stop steel plate flange assembly is located in the middle of the station's bottom concrete structure, while the upper layer water-stop steel plate flange assembly and the lower layer water-stop steel plate flange assembly are located 300mm above and below the intermediate layer water-stop steel plate flange assembly, respectively.
3. The subway foundation dewatering well sealing device according to claim 2, characterized in that: The three layers of waterstop steel plates (4) are arranged in a staggered manner, and the angle between the joint positions of two adjacent layers of waterstop steel plates (4) is 30°.
4. The subway foundation dewatering well water stop device according to claim 2, characterized in that: The rubber waterstop (2) is a 10mm thick and 50mm wide circular waterstop strip. It is attached to the outside of the drainage well shaft (1) with waterproof adhesive within the width range. The pressure plate (3) is a 4mm thick and 40mm wide steel plate. The upper end of the pressure plate (3) is lower than the upper end of the rubber waterstop (2).
5. The subway foundation dewatering well sealing device according to claim 4, characterized in that: The water-stop steel plate (4) is a semi-circular steel plate with a thickness of 4mm and a width of 100mm. The water-stop steel plate (4) is welded perpendicularly to the adhesive steel plate (3).
6. The subway foundation dewatering well sealing device according to claim 5, characterized in that: Each set of angle steel connecting plates (5) includes two L-shaped angle steels. The two L-shaped angle steels are symmetrically arranged at both ends of the two water-stop steel plates (4). The vertical part of the L-shaped angle steel is provided with multiple bolt holes. The vertical parts of the two L-shaped angle steels in each set of angle steel connecting plates (5) are attached to each other and fastened by bolts (6).