Post-grouting Larsen steel sheet pile composite structure and mounting method thereof
By using a post-grouting Larssen sheet pile composite structure, combined with the joint support and waterproof layer design of sheet piles, the problems of high flexibility and poor waterproof performance of traditional sheet pile support structures are solved, achieving high rigidity and waterproof effect, which is suitable for deep foundation pit projects.
Patent Information
- Application Number
- CN202511325648.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-17
- Publication Date
- 2025-11-04
AI Technical Summary
Traditional steel sheet pile support structures have high flexibility in deep foundation pit engineering, poor waterproof performance, and are difficult to meet the design and construction requirements of complex foundation pits. In addition, they have low design applicability, are difficult to adjust in a flexible manner, and have low reuse rate.
The structure adopts a post-grouting Larssen sheet pile composite structure. Through the joint support of the front and rear rows of sheet piles, combined with H-shaped connecting steel plates and reserved grouting pipes, waterproof material is injected to form a waterproof layer, which enhances the structural rigidity and waterproof performance.
It significantly improves the stiffness and waterproof performance of the support structure, controls the deformation of the foundation pit, simplifies construction, reduces costs, minimizes environmental impact, and adapts to the needs of complex projects.
Smart Images
Figure CN120889283A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of deep foundation pit engineering, and particularly relates to a post-grouting type Larsen steel sheet pile combined structure and a mounting method thereof. BACKGROUND
[0002] In recent years, with the continuous advancement of urbanization in China, the construction scale of urban high-rise buildings and underground projects is increasing, and deep, large, near and tight deep foundation pit projects are increasing (Zheng G, et al. Foundation pit engineering and underground engineering safety and environmental influence control [J]. Journal of Civil Engineering, 2016, 49(06): 1-24.). The rapid development of deep foundation pit engineering makes foundation pit support a current research hotspot. The foundation pit support structure is different from the general slope retaining structure and belongs to a temporary support measure. In order to save costs, the design safety factor is usually low. At the same time, the foundation pit engineering is greatly affected by the regional geological environment, making the foundation pit support system have great uncertainty and risk. When the foundation pit support structure is insufficient and the waterproof performance is poor, it will lead to the instability and collapse of the foundation pit and even cause damage to the adjacent buildings, endangering the safety of construction personnel and mechanical equipment. Therefore, it is an urgent requirement of engineering practice to carry out systematic research on the deep foundation pit support system.
[0003] At present, various support structure types are used in foundation pit engineering, which can be divided into two categories: pile (wall) type support system and gravity type support system, and can be divided into soil (water) retaining and support and tie two parts. For deep foundation pit engineering in different regions, the traditional support form is difficult to meet the complex requirements of deep foundation pit design and construction. Steel sheet pile support has been widely used in the field of foundation pit engineering due to its good working performance, convenient and fast construction, and green environmental protection and other advantages. However, the traditional steel sheet pile support has a large flexibility, and when the support or anchor system is improperly arranged, a large deformation will occur. In addition, the traditional steel sheet pile has poor waterproof performance and is prone to water leakage. Therefore, a new optimized scheme more suitable for modern foundation pit support needs to be proposed to meet the requirements of various complex factors. In practice, in order to reduce and control the displacement deformation of the steel sheet pile support structure, various new combined support forms are proposed, but the design of the steel sheet pile combined support at present is mostly based on a specific project and focuses on meeting the stability requirements of the foundation pit of the project. A systematic design method has not yet been formed, and there are disadvantages such as low applicability, difficult to flexibly adjust the design size, and low reuse rate.
[0004] For different regions of deep foundation pit engineering, the traditional steel sheet pile support form is difficult to meet the complex foundation pit design and construction requirements, in order to solve this problem, domestic and foreign experts and scholars put forward a variety of combined steel sheet pile support form. A kind of HSW method pile foundation pit support structure is proposed by setting H type steel pile outside U type steel sheet pile (Li Renmin, etc. Large diameter circular steel sheet pile cofferdam construction technology [J]. Construction technology. 2013.). U type steel sheet pile mainly plays the role of retaining soil and water, H type steel pile can improve the overall rigidity of the support structure. Further research on the combined support structure of steel sheet pile and pipe pile is carried out, and the design calculation method of the structure is put forward (Li Xuefeng. Numerical simulation and application research of deep foundation pit support based on steel pipe and steel sheet pile combined support structure (PUC) [D]. Anhui University of Technology, 2019.), the reliability of the calculation method is verified based on the actual engineering monitoring data. The emergence of these new combined structure forms reflects the shortcomings of small rigidity of steel sheet pile support structure, but the steel sheet pile combined structure form combining foundation pit seepage prevention and support has not been reported. SUMMARY
[0005] In order to overcome the defects existing in the prior art, the purpose of the present application is to provide a post grouting type Larsen steel sheet pile combined structure and its installation method, which resists soil pressure by the combined support effect of steel sheet pile, and the coordinated action of rib plate can fully play the self stability performance of the soil around the structure, so that the support system has greater structural rigidity and can more effectively control the deformation of foundation pit; at the same time, the reserved grouting pipeline is filled with waterproof material along the pipeline after the steel sheet pile is driven in, a waterproof layer is formed at the connection of the steel sheet pile, and the purpose of water stop is realized; the problems of small rigidity, large deformation and poor seepage prevention of steel sheet pile are solved, and the advantages of large support rigidity and excellent seepage prevention are provided, which provides a new choice for deep foundation pit support engineering.
[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is:
[0007] A post grouting type Larsen steel sheet pile combined structure, comprising front row steel sheet pile 1, rear row steel sheet pile 2 and H type connecting steel sheet 3 connected between the front row steel sheet pile 1 and the rear row steel sheet pile 2; the front row steel sheet pile 1 and the rear row steel sheet pile 2 are both U type steel sheet, and a plurality of front row steel sheet piles 1 are connected in sequence to form a front row steel sheet pile wall 4 with the openings of the front row steel sheet piles 1 being opposite to each other; the front of the front row steel sheet pile wall 4 is a foundation pit free face, and the back of the front row steel sheet pile wall 4 and the convex surface of the front row steel pile 1 are both provided with a wing plate 7 on the concave surface of the front of the rear row steel sheet pile 2, and the H type connecting steel sheet 3 is clamped into the wing plate 7 to connect the front row steel sheet pile 1 and the rear row steel sheet pile 2; the back of the connection between adjacent front row steel sheet piles 1 is reserved with a grouting pipeline 5.
[0008] The front row steel sheet pile 1 and the rear row steel sheet pile 2 use U type steel sheet with narrow opening at the bottom and wide opening at the top.
[0009] The end of the two side ribs 8 of the front row of steel sheet piles 1 is turned outward to form a hook-shaped outward turning structure 9.
[0010] The front row of steel sheet piles 1 are buckled by the hook-shaped outward turning structure 9 of the end of the rib 8 of the front row of steel sheet piles 1 to form a front row of steel sheet pile wall 4.
[0011] The grouting pipe 5 is provided with a plurality of grouting holes 6.
[0012] A method for installing a rear grouting type Larsen steel sheet pile combined structure, specifically comprising the following steps:
[0013] Step 1: According to the layout design of the foundation pit, the front row of steel sheet piles 1 are driven in, the front row of steel sheet piles 1 are tightly buckled by the hook-shaped outward turning structure 9 of the end of the two side ribs 8 of the front row of steel sheet piles 1 between adjacent front row of steel sheet piles 1 to form a front row of steel sheet pile wall 4; the back of the connection between adjacent front row of steel sheet piles 1 is reserved for a grouting pipe 5;
[0014] Step 2: The position of the H-shaped connecting steel plate 3 reserved behind the convex surface of the front row of steel sheet piles 1 is then reserved, and then the rear row of steel sheet piles 2 are driven in;
[0015] Step 3: Then, the H-shaped connecting steel plate 3 is driven into the wing plate 7 provided on the convex surface of the front row of steel piles 1 and the concave surface of the rear row of steel sheet piles 2 to realize the connection between the front row of steel sheet piles 1 and the rear row of steel sheet piles 2;
[0016] Step 4: The waterproof material is grouted along the reserved grouting pipe 5 to form a waterproof and anti-seepage layer 10 at the connection between the two front row of steel sheet piles 1, thereby realizing the supporting function while preventing seepage and water.
[0017] In the steps 1 to 3, the pile body of the front row of steel sheet piles 1 and the rear row of steel sheet piles 2 should be accurately positioned, and the perpendicularity of the pile body and the H-shaped connecting steel plate 3 should meet the requirements of pile driving.
[0018] The waterproof material includes water glass or cement slurry.
[0019] Compared with the prior art, the present application has the following beneficial effects:
[0020] (1) The rigidity is greatly improved: in actual engineering, the control ability of the steel sheet pile support on the deformation of the foundation pit is often limited by the bending rigidity of the structure; the present application resists the earth pressure by combined support, and the cooperative action of the ribs can fully utilize the self-stability of the soil around the structure, so that the supporting system has greater structural rigidity and can more effectively control the deformation of the foundation pit.
[0021] (2) Good waterproofness: the present application combines with the rear grouting type construction, and by pre-setting the grouting pipe, the waterproof material is grouted in the pipe after pile driving, which can greatly prevent water from seeping in.
[0022] (3) Construction is simple and fast: the post-grouting Larsen steel sheet pile composite structure, each component can be prefabricated in the factory, directly installed on site, convenient construction, greatly shorten the construction period, in the small construction space, tight construction period, complex construction environment project can show more advantages.
[0023] (4) Economic and practical: compared with the measures of increasing section height and increasing steel sheet pile wall thickness, the post-grouting Larsen steel sheet pile composite structure has low material cost and high efficiency, which can greatly improve the bending stiffness of the supporting structure while ensuring the economy of the project; rib support structure can also reduce earth excavation in engineering, has good durability and can be reused.
[0024] (5) The post-grouting Larsen steel sheet pile composite structure does not need to make a large amount of concrete on the construction site when installed and used, reducing the consumption of land resources and avoiding environmental pollution; and it does not need to occupy a large amount of construction space, the construction noise is greatly reduced, and the influence on the surrounding environment and the life of the surrounding residents is also greatly reduced.
[0025] In summary, the overall stiffness of the post-grouting Larsen steel sheet pile composite structure is greatly increased, and the ability of the structure to resist soil pressure and control the deformation of the foundation pit is further enhanced, so the application prospect in deep foundation pit engineering is promising. BRIEF DESCRIPTION OF DRAWINGS
[0026] Figure 1 The post-grouting Larsen steel sheet pile composite structure is shown in the figure.
[0027] Figure 2 The post-grouting Larsen steel sheet pile composite structure is shown in the figure.
[0028] Figure 3 The post-grouting Larsen steel sheet pile composite structure is shown in the figure.
[0029] Figure 4 The post-grouting Larsen steel sheet pile composite structure is shown in the figure.
[0030] Figure 5 The post-grouting Larsen steel sheet pile composite structure is shown in the figure.
[0031] Figure 6 The post-grouting Larsen steel sheet pile composite structure is shown in the figure.
[0032] Figure 7 The post-grouting Larsen steel sheet pile composite structure is shown in the figure.
[0033] Figure 8 The post-grouting Larsen steel sheet pile composite structure is shown in the figure. DETAILED DESCRIPTION
[0034] The application will be described in detail below with reference to the drawings and specific embodiments.
[0035] As Figures 1 to 8 A post-grouting Larsen steel sheet pile combined structure, comprising front row steel sheet piles 1, rear row steel sheet piles 2 and H-shaped connecting steel sheets 3 connected between the front row steel sheet piles 1 and the rear row steel sheet piles 2. Figure 7 The front row steel sheet piles 1 and the rear row steel sheet piles 2 are both U-shaped steel sheets. Figure 6 The openings of the front row steel sheet piles 1 are connected in order of one positive and one negative to form a front row steel sheet pile wall 4. Figure 1 The front of the front row steel sheet pile wall 4 is a pit free surface, and the rear of the front row steel sheet pile wall 4 and the convex surface of the front row steel pile 1 are both provided with wing plates 7 on the concave surface of the front of the rear row steel sheet piles 2. Figure 4 , Figure 8 The H-shaped connecting steel sheets 3 are clamped into the wing plates 7 at both ends to connect the front row steel sheet piles 1 and the rear row steel sheet piles 2. Figure 3 .
[0036] The front row steel sheet piles 1 and the rear row steel sheet piles 2 use U-shaped steel sheets with narrow openings at the bottom. Figure 6
[0037] The end of the rib plate 8 of the front row steel sheet pile 1 is turned outward to form a hook-shaped outward turning structure 9. Figure 3 .
[0038] The plurality of front row steel sheet piles 1 are connected by the hook-shaped outward turning structure 9 of the end of the rib plate 8 of the front row steel sheet pile 1 to form the front row steel sheet pile wall 4.
[0039] The grouting pipe 5 is provided with a plurality of grouting holes 6 for pouring waterproof material into the outside. Figure 2 , Figure 5 .
[0040] A mounting method of a post-grouting Larsen steel sheet pile combined structure, specifically comprising the following steps:
[0041] Step 1: According to the pit arrangement design, the front row steel sheet piles 1 are driven in, the hook-shaped outward turning structure 9 of the end of the rib plate 8 of the front row steel sheet pile 1 is tightly connected between adjacent front row steel sheet piles 1 to form a front row steel sheet pile wall 4, and the back of the connection between adjacent front row steel sheet piles 1 is reserved with a grouting pipe 5.
[0042] Step 2: The position of the H-shaped connecting steel sheet 3 is reserved behind the convex surface of the front row steel sheet pile 1, and then the rear row steel sheet pile 2 is driven in.
[0043] Step 3, then, the convex surface of the front row of steel piles 1 and the concave surface of the rear row of steel piles 2 are arranged in the wing plate 7, and the H-shaped connecting steel plate 3 is punched, so that the front row of steel piles 1 and the rear row of steel piles 2 are connected;
[0044] Step 4, the waterproof material is poured along the reserved grouting pipe 5, and the waterproof and anti-seepage layer 10 is formed at the connecting part between the two front rows of steel piles 1, so that the supporting function is realized while the waterproof and anti-seepage are realized.
[0045] In the piling of steps 1 to 3, the pile body of the front row of steel piles 1 and the rear row of steel piles 2 should be accurately positioned, and the verticality of the pile body and the H-shaped connecting steel plate 3 should meet the piling requirements.
[0046] In the piling of steps 1 to 3, the pile body of the front row of steel piles 1 and the rear row of steel piles 2 should be accurately positioned, and the verticality of the pile body and the H-shaped connecting steel plate 3 should meet the piling requirements.
[0047] In the piling of steps 1 to 3, the pile body of the front row of steel piles 1 and the rear row of steel piles 2 should be accurately positioned, and the verticality of the pile body and the H-shaped connecting steel plate 3 should meet the piling requirements.
[0048] The waterproof material includes water glass or cement slurry.
[0049] The structure of the application resists earth pressure by combined supporting effect, and the cooperation of the rib plate can fully exert the self-stability performance of the soil around the structure, so that the supporting system has greater structural rigidity and can more effectively control the deformation of the foundation pit. At the same time, the grouting pipe is reserved, and after the steel piles are punched, the waterproof material (water glass or cement slurry) is poured along the pipe to form a waterproof layer at the connecting part of the two steel piles, so as to realize the purpose of anti-seepage and water stop.
[0050] The front row of steel piles 1 in the application plays a main role in supporting and retaining soil, and the rear row of steel piles 2 and the H-shaped connecting steel plate 3 form a rear pulling effect on the front row of steel piles 1, fully exerting the self-stability performance between the rear soil and the piles, changing the cantilever beam support into a form of "cantilever beam support + pull rod" support, which can achieve a larger supporting effect with smaller cost. At the same time, the post-grouting technology realizes the anti-seepage of the steel piles, so that the steel piles themselves form a strict anti-seepage system, saving cost. From the principle, the application conforms to the principle of mechanics and has good effect.
Claims
1. A post-grouted Larssen sheet pile composite structure, comprising a front row of sheet piles (1), a rear row of sheet piles (2), and an H-shaped connecting steel plate (3) connecting the front row of sheet piles (1) and the rear row of sheet piles (2); characterized in that, Both the front row sheet piles (1) and the rear row sheet piles (2) are made of U-shaped steel plates. The openings of multiple front row sheet piles (1) are connected sequentially in opposite directions to form a front row sheet pile wall (4). The front of the front row sheet pile wall (4) is the open surface of the foundation pit. The rear of the front row sheet pile wall (4) and the convex surface of the front row sheet piles 1 and the concave surface of the rear row sheet piles (2) are provided with wing plates (7). The two ends of the H-shaped connecting steel plate (3) are inserted into the wing plates (7) to connect the front row sheet piles (1) and the rear row sheet piles (2). Grouting pipes (5) are reserved on the back of the connection of adjacent front row sheet piles (1).
2. The post-grouting Larssen sheet pile composite structure according to claim 1, characterized in that, The front row of sheet piles (1) and the rear row of sheet piles (2) use U-shaped steel plates with narrow bottoms and wide openings.
3. The post-grouting Larssen sheet pile composite structure according to claim 1, characterized in that, The ends of the two side ribs (8) of the front sheet pile (1) are turned outward to form a hook-shaped outward structure (9).
4. The post-grouting Larssen sheet pile composite structure according to claim 1, characterized in that, The multiple front-row sheet piles (1) are connected by hook-shaped outward-turning structures (9) at the ends of the ribs (8) of the front-row sheet piles (1) to form a front-row sheet pile wall (4).
5. A post-grouted Larssen sheet pile composite structure according to claim 1, characterized in that, The grouting pipe (5) is provided with multiple grouting holes (6).
6. An installation method for a post-grouted Larssen sheet pile composite structure according to any one of claims 1 to 5, characterized in that, Specifically, the following steps are included: Step 1: According to the foundation pit layout design, drive in the front row of steel sheet piles (1). The adjacent front row of steel sheet piles (1) are tightly connected by the hook-shaped outward-turning structure (9) at the ends of the ribs (8) on both sides of the front row of steel sheet piles (1) to form a front row of steel sheet pile wall (4). A grouting pipe (5) is reserved on the back of the connection between the adjacent front row of steel sheet piles (1). Step 2: Reserve the position of H-shaped connecting steel plate (3) behind the convex surface of the front row of sheet piles 1, and then drive in the rear row of sheet piles (2); Step 3: Then, H-shaped connecting steel plates (3) are driven into the wing plates (7) set on the convex surface of the front row steel piles (1) and the concave surface of the rear row steel sheet piles (2) to realize the connection between the front row steel sheet piles (1) and the rear row steel sheet piles (2). Step 4: Waterproof material is injected along the reserved grouting pipe (5) to form a waterproof and seepage-proof layer (10) at the connection between the two front row steel sheet piles (1), thereby achieving the support function while preventing seepage and waterproofing.
7. The installation method of the post-grouting Larssen sheet pile composite structure according to claim 6, characterized in that, During the piling process in steps 1 to 3, it should be ensured that the front row of sheet piles (1) and the rear row of sheet piles (2) are accurately positioned and that the verticality of the piles and the H-shaped connecting steel plates (3) meets the piling requirements.
8. The installation method of the post-grouting Larssen sheet pile composite structure according to claim 6, characterized in that, The waterproofing material includes water glass or cement slurry.