Construction auxiliary structure for ultra-deep hollow pile diaphragm wall

Abstract

The utility model belongs to the technical field of building construction, and relates to a construction auxiliary structure for an ultra-deep hollow pile diaphragm wall, which comprises a groove body and a reinforcement cage assembly, the reinforcement cage assembly is positioned in the groove body, and the reinforcement cage assembly is formed by sequentially and fixedly connecting an extended hollow pile retaining wall section and a reinforcement cage body section from top to bottom; and the height of the extended hollow pile protection wall section is matched with the depth of the hollow pile section of the groove body. The underground diaphragm wall can solve the problem of underground diaphragm wall construction required by application scenes of ultra-deep hollow piles and complex soil layers.

Description

Technical Field

[0001] The utility model relates to the technical field of building construction, and specifically relates to a construction auxiliary structure for ultra-deep hollow pile ground-connected walls. Background Art

[0002] With the rapid development of urban construction, the construction of underground buildings is increasing day by day. As an important supporting structure of underground buildings, the requirements for the depth, quality and construction speed of underground continuous walls are also increasing.

[0003] Patent document number CN117344714A discloses an underground continuous wall construction process, and its technical solution is as follows: an underground continuous wall construction process, comprising the following steps in sequence: 1) preliminary preparation work, leveling the site; 2) building a guide wall; 3) excavating an underground continuous wall trench; 3.1) using a hydraulic grab trenching machine to excavate the soil layer segment; 3.2) using a pile driver with round and square hammers to excavate the rock layer segment; 4) hanging and placing a steel cage; 5) pouring underwater concrete; the underwater concrete includes cement, coarse and fine aggregates, a water reducer and a retarder; wherein the retarder is sodium sulfonate modified nano-silica particles. However, when the above-mentioned construction process is used for the application scenario of ultra-deep hollow piles, the following usage problems are prone to occur: ultra-deep hollow piles often need to be constructed extremely deep underground, and the soil layers involved may be very complex, including high-strength rock layers, sand layers, clay layers, etc. However, the hydraulic grab bucket trench wall machine and pile driver with round and square hammers used in this process may encounter difficulties when dealing with geological or high-strength rock formations that are prone to collapse. Secondly, this construction process also has certain limitations for the application requirements of complex soil layers. Complex soil layers may include soft soils, soils with high water content, etc., and construction in these soil layers requires consideration of more engineering and technical issues. Although the method of pouring underwater concrete is used in the process, when dealing with complex soil layers, problems such as cement slurry leakage and uneven curing may occur, affecting the overall quality and stability of the wall. In particular, the retarder is sodium sulfonate modified nano-silica particles, which has limited ability to solve the permeability and stability problems that may exist in complex soil layers.

[0004] At present, the design form of ground-anchored wall in China is rarely used in empty pile scenarios, and ground-anchored wall with empty piles over 10m is even rarer, lacking mature engineering technology and experience. With the development of the times, it is of great significance to develop an underground continuous wall construction method that can be applied to ultra-deep empty pile application scenarios. Utility Model Content

[0005] In order to overcome the defects of the prior art, the technical problem to be solved by the utility model is to propose a construction auxiliary structure for ultra-deep hollow pile ground-anchored walls to solve the ground-anchored wall construction problems required by application scenarios of ultra-deep hollow piles and complex soil layers.

[0006] To achieve this purpose, the utility model adopts the following technical solutions:

[0007] A construction auxiliary structure for an ultra-deep hollow pile ground-connected wall comprises a trough body and a steel cage assembly. The steel cage assembly is located in the trough body and is formed by fixing an extended hollow pile wall section and a steel cage body section in sequence up and down. The height of the extended hollow pile wall section matches the depth of the hollow pile section of the trough body.

[0008] An optimal technical solution of the utility model is that guide walls are arranged at the top of the trough body, and the guide walls are arranged opposite to each other.

[0009] The preferred technical solution of the utility model is that the guide wall is in an inverted "L" shape.

[0010] An optimal technical solution of the utility model is that the length of the lower extension section of the guide wall is 1-2m.

[0011] The preferred technical solution of the utility model is that steel bar trusses are arranged between the extended empty pile wall protection sections.

[0012] An optimal technical solution of the utility model is that the verticality of the trough body is less than 1 / 300.

[0013] The preferred technical solution of the utility model is that the extended empty pile wall protection section is an I-shaped steel plate.

[0014] Beneficial effects of the utility model:

[0015] The utility model proposes a construction auxiliary structure for ultra-deep empty pile ground-connected walls. The steel cage assembly is located in the trough body, and is formed by extending the empty pile wall protection section and the steel cage body section, which are fixedly connected in sequence from top to bottom. The structural design of the utility model ensures the stability and reliability of the construction process in the ultra-deep empty pile scene. The height of the extended empty pile wall protection section matches the depth of the empty pile section of the trough body, ensuring the correct positioning and stable matching of the steel cage assembly during the construction process. Secondly, the technical solution fully considers the situation of complex soil layers. By using the extended empty pile wall protection section, it is possible to effectively cope with the changes in different soil layers and complex geological conditions, ensuring safety and stability during the construction process. This combination of the trough body and the steel cage assembly designed for complex soil layers completely isolates the sand layer, clay and other unfavorable soil layers at the empty pile position from the source, solves the risk of easy hole collapse at the empty pile part of the ground-connected wall, enables construction personnel to better adapt to various geological conditions, and improves construction efficiency and success rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 This is a schematic diagram of a construction auxiliary structure for an ultra-deep hollow pile ground-connected wall according to the utility model;

[0018] Figure 2 Schematic diagram of the steel cage assembly.

[0019] In the figure:

[0020] 1-Trough body; 11-Empty pile section; 12-Ground-connected wall section; 2-Reinforcement cage assembly; 21-Extended empty pile wall section; 22-Reinforcement cage body section; 23-Reinforcement truss; 3-Guide wall; 31-Lower extension section; 4-Ground. DETAILED DESCRIPTION

[0021] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0022] In this embodiment, a certain engineering project was undertaken, the foundation pit depth was 24.35 to 24.83m, and the retaining structure used a 1000mm thick underground continuous wall with I-beam joints. The ground-connected wall of this project is located at the junction of the large pit and the small pit. There are 13.8m ultra-deep empty piles in the ground-connected wall. During the trenching process, there are many sand layer collapse phenomena. After continuously improving the wall protection mud ratio and increasing the mud specific gravity, the trenching machine is able to protect the wall in the sand layer. However, new problems also arise at the same time. The increase in mud specific gravity makes the secondary hole cleaning more difficult, making it difficult to clean the slag and even causing slag inclusions, and increasing the difficulty of pouring concrete, affecting the construction quality and efficiency. The construction is difficult, and special construction auxiliary structures are required to complete the project.

[0023] like Figure 1-2As shown, for the above-mentioned application scenario, the construction auxiliary structure for the ultra-deep hollow pile ground-connected wall of this embodiment is adopted, including a trough 1 excavated on the ground 4 and a steel cage assembly 2, the trough 1 is composed of an empty pile section 11 and a ground-connected wall section 12, and the steel cage assembly 2 is located in the trough 1; the steel cage assembly 2 is formed by the extended empty pile wall section 21 and the steel cage body section 22 being fixedly connected in sequence up and down, and the height of the extended empty pile wall section 21 matches the depth of the empty pile section 11 of the trough 1. First, the structural design of the trough and the steel cage assembly mentioned in the technical solution of this embodiment fully considers the special needs of ultra-deep hollow pile construction. The steel cage assembly is located in the trough, and is formed by the extended empty pile wall section and the steel cage body section being fixedly connected in sequence up and down. This structural design ensures stability and reliability during the construction process. The height of the extended empty pile wall section matches the depth of the empty pile section of the trough, ensuring the correct positioning and stable connection of the steel cage assembly during construction. Secondly, the scheme fully considers the situation of complex soil layers. By using an extended hollow pile wall section, we can effectively cope with the changes in different soil layers and complex geological conditions, ensuring safety and stability during the construction process. This combination of trough and steel cage assemblies designed for complex soil layers enables construction personnel to better adapt to various geological conditions, improving construction efficiency and success rate. Finally, the innovation of this technical solution lies in its comprehensive consideration of multiple key factors in ultra-deep hollow pile construction, and the targeted design of the trough and steel cage assembly, thus solving problems that are difficult to deal with by traditional construction methods. By optimizing the structural design and construction process, the construction efficiency is improved, the construction risk is reduced, and an innovative solution is provided for ultra-deep hollow piles and engineering construction under complex soil layers.

[0024] Furthermore, a guide wall 3 is provided at the top of the trough body 1, and the guide wall 3 is relatively arranged. The setting of the guide wall can enhance the stability of the trough body, especially in the construction of ultra-deep hollow piles, because the stability of the structure is crucial due to the pressure of the soil layer and the influence of other external forces. The relative setting of the guide wall can effectively improve the overall rigidity and anti-overturning ability of the trough body, and reduce the instability caused by the change of the soil layer during the construction process. The setting of the guide wall can help ensure the accurate positioning and firm connection of the trough body, thereby improving the construction efficiency. In the construction steps such as the installation of the steel cage assembly, the stability and accuracy of the trough body are crucial to the smooth progress of the process. The relative setting of the guide wall can provide reliable support for the construction, reduce the number of adjustments and corrections, and save construction time and labor costs.

[0025] Preferably, the guide wall 3 is in an inverted "L" shape. The inverted "L" shaped guide wall provides a larger support area relative to the upright guide wall under the same size. This design can more effectively disperse the pressure of the soil layer on the top of the trough body, enhance the support effect, reduce the deformation and displacement of the trough body, and thus ensure the safety and stability of the construction. In addition, the inverted "L" shaped guide wall design can make better use of space, especially in limited construction space, this design can provide a larger support area, while occupying relatively small space. This is very important for ultra-deep hollow pile construction in the city center or narrow construction site, which can maximize the optimization of the construction layout and improve the construction efficiency. Further, the length of the lower extension section 31 of the guide wall 3 is 1-2m. The lengthening of the lower extension section of the guide wall increases the support depth of the guide wall, which can better withstand the pressure of the deep soil. This is particularly important for ultra-deep hollow pile construction, because the increase in construction depth will increase the effect of soil pressure, and the lengthening of the lower extension section of the guide wall can effectively cope with this challenge and ensure the stability and safety of the trough structure. 1.3m is used in this embodiment.

[0026] Preferably, a steel truss 23 is provided between the extended hollow pile wall sections 21. The provision of the steel truss can increase the connection strength between the extended hollow pile wall sections, thereby improving the stability of the overall structure. Through the reinforcement of the steel truss, the influence of soil pressure and other external loads on the trough structure can be effectively resisted, the deformation and displacement of the structure can be reduced, and the safety and stability of the construction process can be ensured. The provision of the steel truss can increase the anti-extrusion capacity of the trough, especially in the construction of ultra-deep hollow piles, since the pressure of the soil layer may be large, it is particularly important to strengthen the anti-extrusion capacity of the trough structure. The provision of the steel truss can effectively increase the rigidity and bearing capacity of the trough, reduce the influence of soil pressure on the structure, and improve the safety of the construction process.

[0027] Preferably, the length ratio of the extended hollow pile wall section 21 and the steel cage body section 22 is controlled to be (1-1.5):1 in the construction design. By controlling the length ratio of the extended hollow pile wall section and the steel cage body section within the range of (1-1.5):1, the stability and bearing capacity of the structure can be effectively balanced. The extended hollow pile wall section is mainly used to support the soil layer and resist soil pressure, while the steel cage body section is mainly used to bear the load transfer of the pile foundation. By reasonably controlling the length ratio of the two, the structure can maintain stability while meeting the bearing capacity requirements, thereby improving the safety and reliability of ultra-deep hollow pile construction.

[0028] Preferably, the verticality of the tank body 1 is less than 1 / 300. Controlling the verticality of the tank body can ensure that the structure maintains an accurate position and a stable state during the construction process. When the verticality of the tank body meets the requirements, it can ensure that the verticality and horizontality of the ultra-deep hollow pile structure after construction meet the design requirements, reducing the instability and safety hazards caused by structural deflection or tilt.

[0029] Preferably, the bottom sediment thickness of the trough body 1 is not more than 100 mm. Controlling the bottom sediment thickness of the trough body can improve the quality and stability of the project. A thinner sediment layer can better ensure the close connection between the filling layer and the foundation soil layer, reduce the settlement and deformation of the filling layer, and ensure the stability and reliability of the ultra-deep hollow pile structure. In this embodiment, the bottom sediment thickness of the trough body 1 is about 70 mm.

[0030] Preferably, the distance between the extended empty pile wall protection section 21 and the side wall of the trough body 1 is less than 200 mm. Controlling the distance between the extended empty pile wall protection section and the side wall of the trough body can enhance the stability of the structure. A smaller distance can ensure better contact between the extended empty pile wall protection section and the side wall of the trough body, increase the bearing capacity and overall rigidity of the structure, reduce the deformation and displacement of the structure, and improve the safety and reliability of the construction process. Controlling the distance between the extended empty pile wall protection section and the side wall of the trough body can optimize the distribution of soil pressure and reduce the uneven effect of soil pressure on the structure. A smaller distance can reduce the area where soil pressure is concentrated on the side wall of the trough body, reduce the stress concentration of the structure, reduce the risk of structural damage, and increase the service life of the structure, which is conducive to the subsequent recycling of the extended empty pile wall protection section.

[0031] Preferably, the extended empty pile wall protection section 21 is an I-beam. In addition to the I-beam, the extended empty pile wall protection section can also adopt a plug box and other structures. However, as a material for extending the empty pile wall protection section, the I-beam has the characteristics of light weight and simple structure, is easy to process and transport, and is convenient for on-site construction and installation. This can not only reduce the labor cost and time cost of construction, but also improve the efficiency and speed of construction, thereby reducing the risk and uncertainty of construction. Moreover, the I-beam can also be recycled. Specifically, according to the excavation progress of the project, the position of the ground-connected wall is laid out, the excavator driver is briefed and a special person is sent to supervise on site to ensure the integrity of the I-beam. The position of the I-beam is positioned and checked, wherein the recycled I-beam can also be used as a bottom plate force transmission rod after secondary processing, which can effectively reduce the consumption of resources and the impact on the environment, and meet the requirements of sustainable development.

[0032] The present invention is described by preferred embodiments, and those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. The present invention is not limited to the specific embodiments disclosed herein, and other embodiments falling within the claims of this application are within the scope of protection of the present invention.

Claims

1. A construction auxiliary structure for ultra-deep hollow pile ground-connected wall, characterized by: It comprises a tank body (1) and a steel cage assembly (2), wherein the steel cage assembly (2) is located inside the tank body (1); The steel cage assembly (2) is formed by sequentially and fixedly connecting an extended hollow pile wall protection section (21) and a steel cage body section (22) up and down, and the height of the extended hollow pile wall protection section (21) matches the depth of the hollow pile section (11) of the trough body (1).

2. The construction auxiliary structure for ultra-deep hollow pile ground-connected wall according to claim 1 is characterized in that: A guide wall (3) is arranged at the top end of the trough body (1), and the guide walls (3) are arranged opposite to each other.

3. The construction auxiliary structure for ultra-deep hollow pile ground-connected wall according to claim 2 is characterized in that: The guide wall (3) is in an inverted "L" shape.

4. The construction auxiliary structure for ultra-deep hollow pile ground-connected wall according to claim 3 is characterized in that: The length of the lower extension section (31) of the guide wall (3) is 1-2 m.

5. The construction auxiliary structure for ultra-deep hollow pile ground-connected wall according to claim 1 is characterized in that: A steel bar truss (23) is arranged between the extended hollow pile wall protection sections (21).

6. The construction auxiliary structure for ultra-deep hollow pile ground-connected wall according to claim 1 is characterized by: The verticality of the tank body (1) is less than 1 / 300.

7. The construction auxiliary structure for ultra-deep hollow pile ground-connected wall according to claim 1 is characterized by: The extended hollow pile wall protection section (21) is an I-shaped steel plate.

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