Production method and construction method of assembly type high-strength toughness composite prefabricated stand column pile

Abstract

The invention discloses a production method and a construction method of an assembly type high-strength toughness composite prefabricated stand column pile, and belongs to the technical field of foundation pit supporting. According to the stand column pile production method and the stand column pile construction method, the stand column pile is mainly composed of the foundation pile section, the bottom plate section, the stand column section and the supporting section, the foundation pile section, the bottom plate section, the stand column section and the supporting section of the stand column pile are manufactured through the prefabrication production method, and efficient construction of the stand column pile can be achieved through the field assembly technology of all the pile sections; the strength and toughness reinforcing design of each pile section is combined, so that the upright pile can be constructed by adopting a static pressure process, the construction efficiency is obviously improved, and the construction process is simpler; meanwhile, the foundation pile sections and the stand column sections are assembled and connected through the bottom plate sections, the stand column sections are assembled and connected through the supporting sections, the connection strength is higher, field operation is convenient, due to the fact that the strength and toughness of the stand column pile are improved, brittle failure of the stand column pile in the construction process is avoided, and 100% recycling of the stand column sections of the stand column pile is achieved.

Description

Technical Field

[0001] The invention relates to a column pile for deep foundation pit support and a production and construction method thereof, and more specifically, to a production method and a construction method of an assembled high-strength and toughness composite prefabricated column pile. Background Art

[0002] With the acceleration of urbanization and the deepening of underground space development, deep foundation pit projects play a vital role in projects such as high-rise buildings, subway tunnels, and underground integrated pipe corridors. At the same time, deep foundation pit projects also face multiple challenges such as complex stratum adaptation, green construction, and intelligent construction. As the key vertical load-bearing components in the foundation pit support system, the performance of column piles directly determines the stability of the foundation pit, construction efficiency, and the impact on the surrounding environment. However, there are many problems in the practical application of traditional column pile technology, and it is urgent to achieve breakthroughs through technological innovation to meet the needs of modern engineering construction for high efficiency, environmental protection, economy, and sustainable development.

[0003] Traditional column pile technologies mainly include cast-in-place piles, steel pipe piles, rigid composite piles and prefabricated piles. These column piles have many limitations in construction technology, such as:

[0004] Cast-in-place piles are a common form of column piles, which are formed by drilling holes on site and pouring concrete. Although they have a high bearing capacity, they have a long construction period and are greatly affected by geological conditions. They are prone to problems such as hole collapse and diameter shrinkage. In addition, a large amount of mud will be generated during the construction of cast-in-place piles, which will pollute the environment, and the piles cannot be recycled, which does not conform to the concept of green construction.

[0005] Steel pipe piles have the advantages of fast construction speed, high bearing capacity, and strong anti-deformation ability, but their cost is high and their pull-out resistance is relatively poor. During the recycling process, steel pipe piles usually need to be cut, resulting in serious material waste and making it difficult to meet the requirements of sustainable development.

[0006] The rigid composite piles are reinforced by inserting steel pipes or steel lattice columns inside the piles, but the core problem is that the connection reliability between the prefabricated piles and the steel structure is insufficient. The construction process is complicated, the strength and durability of the connection nodes are difficult to guarantee, and brittle failure is prone to occur under complex geological conditions.

[0007] Precast piles (such as prestressed concrete square piles) have gradually attracted attention due to their advantages such as factory production, fast construction speed and controllable quality. However, traditional precast piles lack toughness and are prone to brittle failure under complex geological conditions. In addition, the design of mechanical connectors between pile sections has the risk of stress concentration, which affects its long-term stability.

[0008] Although some progress has been made in column pile technology in recent years, there are still many unresolved issues, such as:

[0009] High strength and high toughness requirements: Under complex geological conditions, column piles need to have compression resistance, bending resistance and impact resistance to avoid brittle failure. However, in the existing technology, it is difficult to achieve both high strength and high toughness of column piles, especially in deep foundation pits and complex geological environments, where traditional materials and structural forms can no longer meet engineering requirements.

[0010] Recyclability and economy: Most traditional column piles cannot be recycled, which not only causes material waste but also increases project costs. Although some recycling technologies have made certain progress, their recycling process is complex, the operation is difficult, and the adaptability is not high, making it difficult to be widely used in actual projects.

[0011] Optimization of connection nodes: The foundation section of the column pile usually adopts cast-in-place piles or pipe piles. The insufficient strength of the connection node has always been a key problem restricting its performance improvement. In the existing technology, the connection between the pile sections mostly adopts mechanical connectors, which has the risk of stress concentration and affects the long-term stability of the column pile.

[0012] Intelligent construction and monitoring: Although the application of intelligent monitoring technology in column piles is gradually increasing, its system integration cost is high, and the reuse and maintenance costs of sensors cannot be ignored. In addition, in the existing technology, the integration of intelligent construction and monitoring systems is low, making it difficult to achieve full automation and intelligent control of the construction process.

[0013] In summary, the traditional column pile technology has many problems in terms of construction cycle, material recyclability, connection stiffness, environmental impact and intelligent construction. Although the existing improved technology has made some progress, it still cannot fully meet the needs of modern engineering construction for high efficiency, environmental protection, economy and sustainable development. Therefore, the development of an assembled column pile technology with high strength, high toughness, recyclability, connection reliability and intelligent construction has become a technical problem that needs to be solved urgently, and it is also a key direction to promote technological progress in the field of foundation pit support engineering. Summary of the invention

[0014] 1. Technical problem to be solved by the invention

[0015] The purpose of the present invention is to overcome the shortcomings of the existing column pile technology, such as long construction period, poor recyclability, low connection strength, and poor pile body strength and toughness, and to provide an assembled high-strength and toughness composite prefabricated column pile production method and construction method. The technical scheme of the present invention is adopted to manufacture the foundation pile segment, bottom plate segment, column segment and support segment of the column pile through a prefabrication production method, and the efficient construction of the column pile can be achieved through the on-site assembly process of each pile segment. Combined with the strength and toughness enhancement design of each pile segment, the column pile can be constructed by a static pressure process, the construction efficiency is significantly improved, and the construction process is simpler. At the same time, the foundation pile segment and the column segment are assembled and connected through the bottom plate segment, and the column segments are assembled and connected through the support segment, the connection strength is higher, and the on-site operation is convenient. Moreover, due to the improvement of the strength and toughness of the column pile, the brittle damage of the column pile during the construction process is avoided, and the column segment of the column pile is 100% recycled.

[0016] 2. Technical solution

[0017] In order to achieve the above object, the technical solution provided by the present invention is:

[0018] A method for producing an assembled high-strength and toughness composite prefabricated column pile of the present invention comprises the following steps:

[0019] S1. Column pile design: According to the engineering drawings and related materials, the column pile design drawings are prepared; the column pile includes a foundation pile section, a bottom plate section, a column section and a support section, wherein:

[0020] The foundation pile section is a prefabricated square pile, including a steel cage, a pile end steel plate welded part and square pile concrete;

[0021] The bottom plate section comprises a rectangular steel frame and bottom plate section concrete filled in the rectangular steel frame, and a bottom plate section bidirectional steel bar connector for connecting with the steel bar structure in the cast-in-place foundation pit bottom plate in two directions is pre-embedded in the bottom plate section;

[0022] The column section includes an outer steel structure layer and an inner grid structure located inside the outer steel structure layer, and the outer steel structure layer and the inner grid structure are connected as a whole by pouring high-strength concrete;

[0023] The support section includes a support steel frame and support section concrete filled in the support steel frame, and a support section bidirectional steel bar connector for connecting with the steel bar structure in the cast-in-place support beam in two directions is pre-embedded in the support section;

[0024] S2. Prefabricated parts production: According to the design drawings of the column piles, the components of the foundation pile section, bottom plate section, column section and support section are manufactured respectively;

[0025] S3. Assembly and production: Install the components of each pile segment into the corresponding mold, pour concrete separately, and obtain prefabricated foundation pile segments, bottom plate segments, column segments and support segments after solidification.

[0026] Furthermore, in step S2, the pile end steel plate welded parts of the foundation pile segment include a pile end end plate, a pile end connecting angle steel and a pile end gusset plate, the four pile end connecting angle steels are respectively welded and fixed at the four corners of the pile end end plate, and the pile end gusset plate is welded and fixed between adjacent pile end connecting angle steels; in step S3, a group of pile end steel plate welded parts are respectively provided at both ends of the steel cage, and the manufactured foundation pile segment is one of a prefabricated solid square pile, a prefabricated hollow square pile, a prestressed prefabricated solid square pile and a prestressed prefabricated hollow square pile.

[0027] Furthermore, in step S2, the rectangular steel frame of the bottom plate section includes a bottom end plate, a bottom plate section angle steel, a top end plate and a bottom plate section connecting plate, the bottom end plate and the top end plate are fixedly connected by four bottom plate section angle steels, and the four bottom plate section angle steels are connected in turn by the bottom plate section connecting plates; the upper and lower ends of the four bottom plate section angle steels are respectively provided with bottom plate section connecting plates for connecting the foundation pile section and the column section; an inner water stop plate is pre-embedded on the inner side of the rectangular steel frame, and an outer water stop plate and a plurality of bolts are welded to the outer side of the bottom plate section angle steel for a second time after excavation of the foundation pit.

[0028] Furthermore, in step S2, the inner grid structure includes an inner fiber grid, a steel grid and an outer fiber grid, the steel grid is connected by main bars and stirrups, and the inner fiber grid and the outer fiber grid are both made of FRP high-strength fiber mesh; in step S3, the outer fiber grid is located on the outside of the steel grid, and the inner fiber grid is located on the inside of the steel grid.

[0029] Furthermore, in step S2, the outer steel structure layer includes a bottom cover plate, a column section angle steel, a top cover plate, a bottom gusset plate, a top gusset plate and a middle gusset plate, and the bottom cover plate and the top cover plate are connected to form a rectangular frame structure through four column section angle steels, the lower ends of the four column section angle steels are connected in sequence through the bottom gusset plate, and the upper ends are connected in sequence through the top gusset plate, and a number of middle gusset plates are arranged in sequence from top to bottom between the four column section angle steels; in step S3, polypropylene fiber reinforcement material is added to the high-strength concrete.

[0030] Furthermore, in step S3, a foundation pit section monitoring sensor and a wireless communication module are also built into the column section, and the foundation pit section monitoring sensor is communicatively connected with the background monitoring system via the wireless communication module.

[0031] Furthermore, in step S2, a pneumatic fragmentation device is also provided in the supporting steel frame, and the pneumatic fragmentation device has an outer lead pipe and a cover detachably installed at the end of the outer lead pipe, and a liquid carbon dioxide infusion channel, a positive electrode connecting pipe and a negative electrode connecting pipe are respectively provided in the outer lead pipe; in step S3, the outer lead pipe is led outward from one side of the supporting section concrete.

[0032] Furthermore, in step S2, the supporting steel frame includes a lower end plate, a supporting segment angle steel, an upper end plate and a supporting segment connecting plate, the lower end plate and the upper end plate are fixedly connected by four supporting segment angle steels, and the four supporting segment angle steels are connected in turn by supporting segment connecting plates; the upper and lower ends of the four supporting segment angle steels are also respectively provided with supporting segment connecting plates for connecting the column segments.

[0033] The present invention provides a method for constructing column piles prepared by a method for producing assembled high-strength and toughness composite prefabricated column piles, comprising the following steps:

[0034] S1. Equipment debugging: Install the static pile driver according to the construction position of the column pile, and debug the static pile driver to ensure the normal operation of the hydraulic system, electrical system and travel system of the static pile driver; install the pile driver on the static pile driver, and debug the pile driver to ensure that the pile driver can smoothly press the column pile into the designed elevation; remove the pile driver after debugging;

[0035] S2. Construction of foundation pile sections: Use a static pile driver to press the foundation pile sections into the designed elevation. The pile driving speed is controlled at 0.5-1.0 m / min, and the verticality deviation of the foundation pile sections is controlled within 0.5%;

[0036] S3, segmented connection and pile driving: First, connect the column segment through the bottom plate segment at the top of the foundation pile segment, and use a static pile driver to drive the first column segment into the designed elevation; then connect the remaining column segments through the support segment in turn, and use a static pile driver to drive the column segment into the designed elevation in segments; the pile driving speed of the column segment is controlled at 0.5-1.0 m / min;

[0037] S4. Pile driving with pile driver: install the pile driver on the static pile driver and connect it with the last column section. Use the pile driver and the static pile driver to press the last column section into the designed elevation. At this time, the foundation pile section is located in the bottom stratum of the foundation pit, and the column section is located in the foundation pit.

[0038] S5. Connection of foundation pit support beams: After the column piles are driven, the foundation pit soil is excavated, and the support beams are connected to the corresponding support sections layer by layer from top to bottom to support the foundation pit;

[0039] S6. Construction of foundation pit floor: After excavating to the bottom of the foundation pit, start the construction of the foundation pit floor, and connect the foundation pit floor and the floor section together; then construct the main structure in the foundation pit layer by layer from bottom to top.

[0040] Furthermore, after the main structure construction in the foundation pit is completed, the support dismantling and recovery step S7 is entered; in the support dismantling and recovery step S7, the column section is first dismantled, and then the support section and the support beam are dismantled; the recovered and repaired column section is designed and reused according to the design requirements of the next project.

[0041] 3. Beneficial effects

[0042] Compared with the existing known technologies, the technical solution provided by the present invention has the following significant effects:

[0043] (1) The present invention provides a method for producing an assembled high-strength and toughness composite prefabricated column pile, which includes the steps of column pile design, prefabricated parts production and assembly production. The column pile is mainly composed of a foundation pile section, a bottom plate section, a column section and a support section. The foundation pile section, the bottom plate section, the column section and the support section are produced by the prefabrication production method, and the efficient construction of the column pile can be achieved through the on-site assembly process of each pile section; the bottom plate section includes a rectangular steel frame and bottom plate section concrete filled in the rectangular steel frame, the column section includes an outer steel structure layer and an inner grid structure located inside the outer steel structure layer, the outer steel structure layer and the inner grid structure are connected as a whole by high-strength concrete pouring, the support section includes a support steel frame and support section concrete filled in the support steel frame, and the strength and toughness enhancement design of each pile section are combined to enable the column pile to be Static pressure construction can be adopted, construction efficiency is significantly improved, and the construction process is simpler; at the same time, the foundation pile section and the column section are assembled and connected through the bottom plate section, and the column sections are assembled and connected through the support section, the connection strength is higher, and the on-site operation is convenient, and due to the improvement of the strength and toughness of the column piles, the brittle failure of the column piles during the construction process is avoided, and the column sections of the column piles are 100% recycled; in addition, a bottom plate section bidirectional steel bar connector for connecting to the steel bar structure in the cast-in-place foundation pit bottom plate in two directions is pre-embedded in the bottom plate section, and a support section bidirectional steel bar connector for connecting to the steel bar structure in the cast-in-place support beam in two directions is pre-embedded in the support section, which can improve the connection firmness between the foundation pit bottom plate and the column piles, and between the foundation pit support beam and the column piles, and ensure the stability of the deep foundation pit support.

[0044] (2) The present invention provides a method for producing an assembled high-strength and toughness composite prefabricated column pile, wherein the pile end steel plate welded parts of the foundation pile section include a pile end plate, a pile end connecting angle steel and a pile end gusset plate. Compared with the existing prefabricated square piles, a pile end gusset plate design is added to ensure the connection reliability between the foundation pile section and the upper column section.

[0045] (3) The present invention provides a method for producing assembled high-strength and toughness composite prefabricated column piles, wherein the rectangular steel frame of the bottom plate section includes a bottom end plate, a bottom plate section angle steel, a top end plate and a bottom plate section gusset plate, thereby ensuring the structural strength of the bottom plate section; at the same time, an inner water stop plate is pre-buried on the inner side of the rectangular steel frame, and an outer water stop plate and a plurality of bolts are welded to the outer side of the bottom plate section angle steel for a second time after excavation of the foundation pit, thereby solving the water stop problem between the column pile and the bottom plate and the connection reliability problem between the column pile and the bottom plate, and utilizing the foundation pile section to form an effective support for the bottom plate.

[0046] (4) The present invention provides a method for producing an assembled high-strength and toughness composite prefabricated column pile, wherein the inner grid structure of the column section includes an inner fiber grid, a steel grid and an outer fiber grid, the steel grid is formed by connecting main bars and stirrups, and the inner fiber grid and the outer fiber grid are both made of FRP high-strength fiber mesh. The use of the inner and outer fiber grids and the steel grid can further improve the strength and toughness of the column section, and the column section is composited from the inside to the outside through four structural layers, which can reduce the overall steel consumption. While improving the structural strength, toughness and tensile strength of the column pile, the production cost is reduced, so that the column pile has both compression resistance, bending resistance and impact resistance.

[0047] (5) The present invention provides a method for producing an assembled high-strength and toughness composite prefabricated column pile, wherein the outer steel structure layer of the column section includes a bottom cover plate, a column section angle steel, a top cover plate, a bottom gusset plate, a top gusset plate and a middle gusset plate. Compared with the traditional steel lattice column, the column section uses high-strength concrete to cast and connect the outer steel structure layer and the inner grid structure as one, so that the amount of steel used in the outer steel structure layer can be less, thereby reducing the steel use cost of the column section; in addition, polypropylene fiber reinforcement material is added to the high-strength concrete, which can improve the anti-cracking and impact and wear resistance of the concrete, increase the toughness of the concrete, and increase the service life of the column section, thereby meeting the requirements for repeated recycling of the column section.

[0048] (6) The present invention provides a method for producing assembled high-strength and tough composite prefabricated column piles, wherein a foundation pit section monitoring sensor and a wireless communication module are built into the column section. The foundation pit section monitoring sensor is connected to the background monitoring system through the wireless communication module to provide data support for intelligent construction, which is conducive to intelligent control of foundation pit deformation.

[0049] (7) The present invention provides a method for producing assembled high-strength and tough composite prefabricated column piles, wherein a pneumatic crushing device is also provided in the supporting steel frame, which can effectively and conveniently break and remove the supporting section during the dismantling stage, making the dismantling of the supporting beam simple and convenient, while the steel structure of the supporting section can still be recycled for a second time.

[0050] (8) The present invention provides a method for constructing assembled high-strength and tough composite prefabricated column piles, which includes the steps of equipment debugging, foundation pile segment construction, segmented connection and pile driving, pile driving by a pile driver, foundation pit support beam connection and foundation pit bottom plate construction. The foundation pile segment, bottom plate segment and each column segment are segmented and pressed into the foundation pit by a static pile driver, and finally the column pile is pressed into the designed elevation with the help of a pile driver. The entire construction process is simpler and more efficient, with less construction noise and pollution, and the construction depth is not limited in principle. It can be used for foundation pit support with a deeper depth, and has a wider range of applications.

[0051] (9) The present invention provides a method for constructing assembled high-strength and tough composite prefabricated column piles. After the main structure construction in the foundation pit is completed, the method enters the support removal and recovery stage. When the support section is removed, a pneumatic crushing device can be used to break and remove the support section, which facilitates the rapid removal of the cast-in-place support beam, reduces the difficulty of support removal, and improves the support removal efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is a flow chart of a method for producing an assembled high-strength and toughness composite prefabricated column pile according to the present invention;

[0053] Figure 2 It is a schematic diagram of the assembly structure of an assembled high-strength and toughness composite prefabricated column pile of the present invention;

[0054] Figure 3 It is a schematic diagram of the structure and casting of the foundation pile section in the present invention;

[0055] Figure 4 It is a perspective structural schematic diagram of a hollow foundation pile segment in the present invention;

[0056] Figure 5 It is a schematic diagram of the structure and casting of the bottom plate section in the present invention;

[0057] Figure 6 It is a schematic diagram of the structure and casting of the column section in the present invention;

[0058] Figure 7 It is a perspective structural schematic diagram of the hollow column section in the present invention;

[0059] Figure 8 It is a schematic diagram of the cross-sectional structure of the hollow column section in the present invention;

[0060] Fig. 9 It is a schematic diagram of the structure and casting of the support section in the present invention;

[0061] Fig.10 It is a partial enlarged structural schematic diagram of the outer lead pipe of the pneumatic fragmentation device in the present invention;

[0062] Fig.11It is a schematic diagram of the internal cross-sectional structure of the outer lead pipe of the pneumatic fragmentation device in the present invention;

[0063] Fig.12 The present invention is a flow chart of a method for constructing an assembled high-strength and toughness composite prefabricated column pile.

[0064] Explanation of the symbols in the schematic diagram:

[0065] 1. Foundation pile section; 1-1. Steel cage; 1-2. Pile end steel plate weldment; 1-2-1. Pile end plate; 1-2-2. Pile end connecting angle steel; 1-2-3. Pile end plate; 1-3. Square pile concrete;

[0066] 2. Bottom plate section; 2-1. Rectangular steel frame; 2-1-1. Bottom end plate; 2-1-2. Bottom plate section angle steel; 2-1-3. Top end plate; 2-1-4. Bottom plate section gusset plate; 2-1-5. Inner water stop plate; 2-1-6. Bottom plate section connecting plate; 2-2. Bottom plate section two-way steel bar connector; 2-3. Bottom plate section concrete; 2-4. Outer water stop plate; 2-5. Bolts;

[0067] 3. Column section; 3-1. Outer steel structure layer; 3-1-1. Bottom cover plate; 3-1-2. Column section angle steel; 3-1-3. Top cover plate; 3-1-4. Bottom gusset plate; 3-1-5. Top gusset plate; 3-1-6. Middle gusset plate; 3-2. Inner grid structure; 3-2-1. Inner fiber grid; 3-2-2. Steel grid; 3-2-3. Outer fiber grid; 3-3. High-strength concrete;

[0068] 4. Support section; 4-1. Support steel frame; 4-1-1. Lower end plate; 4-1-2. Support section angle steel; 4-1-3. Upper end plate; 4-1-4. Support section gusset plate; 4-1-5. Support section connecting plate; 4-2. Support section two-way steel bar connector; 4-3. Support section concrete; 4-4. Pneumatic fragmentation device; 4-4-1. External lead pipe; 4-4-1a. Liquid carbon dioxide perfusion channel; 4-4-1b. Positive terminal; 4-4-1c. Negative terminal; 4-4-2. Cover. DETAILED DESCRIPTION

[0069] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings and embodiments.

[0070] [Example]

[0071] Combination Figure 1 and Figure 2 As shown, a method for producing an assembled high-strength and toughness composite prefabricated column pile in this embodiment comprises the following steps:

[0072] S1. Column pile design: Prepare column pile design drawings based on engineering drawings and related materials; the above engineering drawings and related materials include but are not limited to:

[0073] Engineering geological survey report: A detailed description of the geological conditions of the area where the foundation pit is located, including soil layer distribution, groundwater level, foundation bearing capacity and other parameters. This information is crucial to determine the design parameters of the column piles, such as the structural form, length, and diameter. For example, in a soft soil foundation, the column piles need to have higher compression and pullout resistance to prevent deformation and leakage of the foundation pit.

[0074] Foundation pit support design drawings: clarify the shape, size, depth of the foundation pit, and the type and layout of the support structure. As a key component in the foundation pit support system, the position, number and spacing of the column piles need to be closely coordinated with the foundation pit support design. For example, in large deep foundation pit projects, the column piles are usually evenly arranged at a certain spacing to ensure the overall stability of the foundation pit.

[0075] Building structure design drawings: Understand the building's structural form, load distribution, and bearing requirements for column piles. Column piles need to bear the vertical load of the superstructure and transfer it to the foundation. Therefore, the load parameters in the building structure design drawings are an important basis for column pile design. For example, for high-rise buildings, column piles need to have a higher bearing capacity to meet the safety requirements of the building.

[0076] Construction organization design documents: including construction schedule, construction process selection, construction equipment configuration, etc. These documents help determine the production schedule and construction sequence of column piles to ensure the coordination between production and construction.

[0077] By collecting and analyzing the above engineering drawings and related materials, designers can fully understand the engineering requirements and site conditions, and provide an accurate basis for the design of column piles. The design drawings of column piles should include the structural form of column piles, the size parameters of column piles, the design of connection nodes, the layout of embedded parts and construction details, etc. Figure 2 As shown, the assembled high-strength and toughness composite prefabricated column pile of this embodiment includes a foundation pile section 1, a bottom plate section 2, a column section 3 and a support section 4, wherein:

[0078] The foundation pile section 1 is a prefabricated square pile, including a steel cage 1-1, a pile end steel plate welded part 1-2 and square pile concrete 1-3;

[0079] The bottom plate section 2 includes a rectangular steel frame 2-1 and a bottom plate section concrete 2-3 filled in the rectangular steel frame 2-1. A bottom plate section bidirectional steel bar connector 2-2 for connecting with the steel bar structure in the cast-in-place foundation pit bottom plate in two directions is pre-embedded in the bottom plate section 2;

[0080] The column section 3 includes an outer steel structure layer 3-1 and an inner grid structure 3-2 located inside the outer steel structure layer 3-1, and the outer steel structure layer 3-1 and the inner grid structure 3-2 are connected as a whole by pouring high-strength concrete 3-3;

[0081] The support section 4 includes a support steel frame 4-1 and support section concrete 4-3 filled in the support steel frame 4-1. A support section bidirectional steel bar connector 4-2 is pre-embedded in the support section 4 for connecting to the steel bar structure in the cast-in-place support beam in two directions.

[0082] Each pile section of the column pile can be designed separately. The relevant design drawings are an important basis for the production and construction of the column piles. Their accuracy and completeness are directly related to the quality and safety of the project.

[0083] S2. Prefabricated parts production: According to the design drawings of the column piles, the pile segment components of the foundation pile segment 1, the bottom plate segment 2, the column segment 3 and the support segment 4 are manufactured respectively. Before starting production, sufficient production preparation is required, including raw material procurement, production equipment commissioning, personnel training, etc. Through sufficient production preparation, a good foundation can be provided for the production of column piles, ensuring the smooth progress of the production process and the stability of product quality.

[0084] S3, assembly and production: install the components of each pile segment into the corresponding mold, pour concrete respectively, and after curing, obtain the prefabricated foundation pile segment 1, bottom plate segment 2, column segment 3 and support segment 4. The inner surface of the mold needs to be smooth and flat to ensure the appearance quality of the column pile.

[0085] The assembled high-strength and toughness composite prefabricated column pile production method of this embodiment uses a prefabrication production method to manufacture the foundation pile segment 1, bottom plate segment 2, column segment 3 and support segment 4 of the column pile, and can achieve efficient construction of the column pile through the on-site assembly process of each pile segment. Combined with the strength and toughness enhancement design of each pile segment, the column pile can be constructed using a static pressure process, the construction efficiency is significantly improved, and the construction process is simpler; at the same time, the foundation pile segment 1 and the column segment 3 are assembled and connected through the bottom plate segment 2, and the column segments 3 are assembled and connected through the support segment 4, the connection strength is higher, and the on-site operation is convenient, and due to the improvement of the strength and toughness of the column pile, the brittle failure of the column pile during the construction process is avoided, and 100% recycling of the column segments of the column pile is achieved. In addition, a bottom plate section bidirectional steel bar connector 2-2 is pre-embedded in the bottom plate section 2 for connecting to the steel bar structure in the cast-in-place foundation pit bottom plate in two directions, and a support section bidirectional steel bar connector 4-2 is pre-embedded in the support section 4 for connecting to the steel bar structure in the cast-in-place support beam in two directions. This can improve the connection firmness between the foundation pit bottom plate and the column piles, and between the foundation pit support beam and the column piles, thereby ensuring the stability of the deep foundation pit support.

[0086] like Figure 3 As shown, in the above step S2, the pile end steel plate welded parts 1-2 of the foundation pile segment 1 include a pile end end plate 1-2-1, a pile end connecting angle steel 1-2-2 and a pile end gusset plate 1-2-3, the four pile end connecting angle steels 1-2-2 are respectively welded and fixed at the four corners of the pile end end plate 1-2-1, and the pile end gusset plate 1-2-3 is welded and fixed between adjacent pile end connecting angle steels 1-2-2. Compared with the existing prefabricated square piles, the pile end gusset plate design is added to ensure the connection reliability between the foundation pile segment 1 and the upper column segment 3. In step S3, a set of pile end steel plate welded parts 1-2 is provided at each end of the steel cage 1-1, and the manufactured foundation pile segment 1 is one of a prefabricated solid square pile, a prefabricated hollow square pile, a prestressed prefabricated solid square pile and a prestressed prefabricated hollow square pile. Figure 4 The figure shows a hollow foundation pile segment 1. The length and width of the pile end connection angle steel 1-2-2 of the pile end steel plate weldment 1-2 can be appropriately increased, and connection screw holes can be reserved thereon to facilitate connection with the bottom plate segment 2. Of course, the foundation pile segment 1 and the bottom plate segment 2 can also be connected by welding.

[0087] like Figure 5 As shown, in the above step S2, the rectangular steel frame 2-1 of the bottom plate section 2 includes a bottom end plate 2-1-1, a bottom plate section angle steel 2-1-2, a top end plate 2-1-3 and a bottom plate section gusset plate 2-1-4, the bottom end plate 2-1-1 and the top end plate 2-1-3 are fixedly connected by four bottom plate section angle steels 2-1-2, and the four bottom plate section angle steels 2-1-2 are connected in turn by the bottom plate section gusset plate 2-1-4. The bottom end plate 2-1-1, the bottom plate section angle steel 2-1-2, the top end plate 2-1-3 and the bottom plate section gusset plate 2-1-4 are all connected and fixed by welding technology. The upper and lower ends of the four bottom plate section angle steels 2-1-2 are also provided with bottom plate section connection plates 2-1-6 for connecting the foundation pile section 1 and the column section 3. The bottom plate section connection plates 2-1-6 can be angle steel structures, which can be connected with the bottom plate section angle steels 2-1-2 and the angle steels at the four corners of the foundation pile section 1 and the column section 3 through flat head bolts, so as to facilitate the rapid disassembly of the column section 3. In addition, an inner water stop plate 2-1-5 is also pre-buried on the inner side of the rectangular steel frame 2-1, and an outer water stop plate 2-4 and a plurality of studs 2-5 are welded to the outer side of the bottom plate section angle steel 2-1-2 for a second time after the foundation pit is excavated. The inner water stop plate 2-1-5 is pre-installed in the bottom plate section 2. Before the construction of the foundation pit bottom plate, the bottom plate section 2 is subjected to secondary welding construction, that is, the outer water stop plate 2-4 and the studs 2-5 are welded and fixed on the outer side of the bottom plate section 2. The outer water stop plate 2-4 and the studs 2-5 can be welded on the bottom plate section angle steel 2-1-2, which solves the water stopping problem between the column pile and the bottom plate and the connection reliability problem between the column pile and the bottom plate, and uses the foundation pile section 1 to form an effective support effect on the bottom plate.

[0088] like Figures 6 to 8As shown, in step S2, the column section 3 adopts a structural layer composite structure, and its inner grid structure 3-2 is located on the inner side of the outer steel structure layer 3-1, and the inner grid structure 3-2 includes an inner fiber grid 3-2-1, a steel grid 3-2-2 and an outer fiber grid 3-2-3, and the steel grid 3-2-2 is connected by main bars and stirrups, and the inner fiber grid 3-2-1 and the outer fiber grid 3-2-3 are both made of FRP high-strength fiber mesh; in step S3, the outer fiber grid 3-2-3 is located on the outside of the steel grid 3-2-2, and the inner fiber grid 3-2-1 is located on the inside of the steel grid 3-2-2. The steel bars used in the steel mesh 3-2-2 should have good welding performance and corrosion resistance to ensure the long-term stability of the column piles; the FRP high-strength fiber mesh has good tensile strength and corrosion resistance, and can effectively improve the toughness of the column piles; in order to ensure the close combination of the FRP high-strength fiber mesh and the steel mesh 3-2-2 (steel cage), it is necessary to set a special connector between the fiber mesh and the steel cage. The connector can be a metal tie or a special fiber reinforced plastic tie to fix the fiber mesh to the steel cage; when fixing, the spacing of the connectors should be uniform, usually not more than 300mm, to ensure that the fiber mesh does not shift during the concrete pouring process. Compared with the existing column pile lattice column, due to the limitation of its own structure, the steel lattice column itself cannot withstand high-pressure extrusion, especially under the condition of static pile holding pressure or top pressure, the steel lattice column is easily damaged by pressure, and in order to prevent the lattice column from brittle failure, the lattice column often needs to be made of thick steel plates and angle steels for welding. The lattice column uses a large amount of steel and has limited compressive and bending resistance. The column section 3 in this embodiment adopts a composite structure, and the inner grid structure 3-2 and high-strength concrete 3-3 enhance the strength of the outer steel structure layer 3-1, and at the same time form an integral column section 3, which jointly exerts compressive, bending and impact resistance. The use of inner and outer fiber grids and steel grids can further improve the strength and toughness of the column section, and the column section 3 is composed of four structural layers from the inside to the outside (inner fiber grid 3-2-1, steel grid 3-2-2, outer fiber grid 3-2-3 and outer steel structure layer 3-1), which can reduce the overall steel consumption, and reduce the production cost while improving the strength, toughness and tensile strength of the column pile structure, so that the column pile has both compression resistance, bending resistance and impact resistance. Further, if Figure 6As shown, in the above step S2, the outer steel structure layer 3-1 includes a bottom cover plate 3-1-1, a column section angle steel 3-1-2, a top cover plate 3-1-3, a bottom gusset plate 3-1-4, a top gusset plate 3-1-5 and a middle gusset plate 3-1-6. The bottom cover plate 3-1-1 and the top cover plate 3-1-3 are connected to form a rectangular frame structure through four column section angle steels 3-1-2. The lower ends of the four column section angle steels 3-1-2 are connected in sequence through the bottom gusset plate 3-1-4, and the upper ends are connected in sequence through the top gusset plate 3-1-5. A number of middle gusset plates 3-1-6 are also arranged in sequence from top to bottom between the four column section angle steels 3-1-2. The structure of the outer steel structure layer 3-1 is similar to that of the existing lattice column, except that the column section 3 uses high-strength concrete 3-3 to cast and connect the outer steel structure layer 3-1 and the inner grid structure 3-2 into one, and the size and thickness of the bottom cover plate 3-1-1, the column section angle steel 3-1-2, the top cover plate 3-1-3, the bottom gusset plate 3-1-4, the top gusset plate 3-1-5 and the middle gusset plate 3-1-6 can be designed to be smaller, and the gusset plate interval can be designed to be larger, so as to reduce the amount of steel used and reduce the steel use cost of the column section. In step S3, polypropylene fiber reinforcement material is added to the high-strength concrete 3-3, which can improve the anti-cracking and anti-abrasion properties of the concrete, increase the toughness of the concrete, and improve the service life of the column section 3, meeting the requirements for repeated recycling of the column section 3. The high-strength concrete 3-3 should have high compressive strength and impermeability, and the polypropylene fiber can improve the crack resistance and toughness of the concrete. During production, the amount of polypropylene fiber should be adjusted according to the design requirements, usually 0.1% to 0.2% of the concrete volume. The length and diameter of the polypropylene fiber should meet the design requirements to ensure its uniform distribution in the concrete; use special concrete mixing equipment to mix the high-strength concrete according to the designed mix ratio; pour the mixed high-strength concrete into the mold of the steel cage and FRP fiber grid. The pouring process should be layered pouring, and the thickness of each layer should not exceed 300mm to ensure the density of the concrete; during the pouring process, use a vibrating rod for vibration. When vibrating, avoid damaging the steel cage and fiber grid. The vibration time should be controlled until floating slurry appears on the concrete surface and there are no bubbles.

[0089] In this embodiment, the column section 3 is a solid or hollow prefabricated pile structure. Figure 7The structure diagram of the hollow column segment is shown. In addition, in step S3, the column segment 3 is also equipped with a foundation pit section monitoring sensor and a wireless communication module. The foundation pit section monitoring sensor communicates with the background monitoring system through the wireless communication module to provide data support for intelligent construction, which is conducive to intelligent control of foundation pit deformation. The foundation pit section monitoring sensor includes sensors such as stress monitors, displacement monitors and axial force detectors. Since the column segment 3 can be 100% recycled, the foundation pit section monitoring sensor and wireless communication module therein can be reused, reducing the sensor reuse and maintenance costs. Specifically, stress sensors can be arranged in the middle of the pile body and at the connection nodes to monitor the stress of the pile body during construction; displacement sensors can be arranged at the top and bottom of the pile to monitor the displacement changes of the pile body. The wireless communication module can use 5G or Internet of Things technology to transmit the data collected by the sensor to the background monitoring system in real time. Through the monitoring system, construction personnel can understand the stress, displacement and strain of the column pile in real time, thereby optimizing construction parameters and ensuring construction quality. Furthermore, the monitoring data can be analyzed to establish a dynamic model of the construction process. Through model analysis, possible problems in the construction process can be predicted and measures can be taken in advance to deal with them. In addition, the monitoring data can be compared with the construction specifications and design requirements to detect deviations in a timely manner and make adjustments. For example, when the displacement of the pile body exceeds the allowable value, the deviation can be corrected by adjusting the pile driving speed or adding support measures.

[0090] Reference Fig. 9 As shown, in the above step S2, since the support section 4 and the support beam are cast in situ to form a support node, considering the difficulty of removing the support beam after casting, the support steel frame 4-1 is also provided with a pneumatic crushing device 4-4, which can effectively and conveniently break and remove the support section 4 during the support removal stage, making the removal of the support beam simple and convenient, and the steel structure of the support section 4 can still be recycled for a second time. Specifically, referring to Figure 10 to Figure 11As shown, the pneumatic fragmentation device 4-4 adopts the principle of gas explosion. The pneumatic fragmentation device 4-4 has an outer lead pipe 4-4-1 and a cover 4-4-2 detachably mounted at the end of the outer lead pipe 4-4-1. The outer lead pipe 4-4-1 is provided with a liquid carbon dioxide perfusion channel 4-4-1a, a positive electrode connecting pipe 4-4-1b and a negative electrode connecting pipe 4-4-1c. In step S3, the outer lead pipe 4-4-1 is led outward from one side of the support section concrete 4-3. During the pressing process, the outer lead pipe 4-4-1 is blocked by the cover 4-4-2 to prevent dirt and other contaminants from entering the outer lead pipe 4-4-1; when casting the support beam, according to the position of the support beam, an external hose can be used to seal the outer lead pipe 4-4-1, and the other end of the external hose extends out of the support beam to facilitate subsequent breaking operations; when dismantling the support, liquid carbon dioxide is injected into the pneumatic fragmentation device 4-4 through the liquid carbon dioxide injection channel 4-4-1a, and the power is turned on through the positive connecting pipe 4-4-1b and the negative connecting pipe 4-4-1c. The liquid carbon dioxide is converted into high-pressure carbon dioxide gas by heating with electrodes, thereby breaking the concrete of the support section 4 from the inside, facilitating the removal of the support beam and the recovery of the support steel frame in the support section 4. Fig. 9 As shown, the above-mentioned support steel frame 4-1 includes a lower end plate 4-1-1, a support section angle steel 4-1-2, an upper end plate 4-1-3 and a support section gusset plate 4-1-4. The lower end plate 4-1-1 and the upper end plate 4-1-3 are fixedly connected by four support section angle steels 4-1-2, and the four support section angle steels 4-1-2 are connected in turn by the support section gusset plate 4-1-4. The lower end plate 4-1-1, the support section angle steel 4-1-2, the upper end plate 4-1-3 and the support section gusset plate 4-1-4 can all be connected and fixed by welding technology. The upper and lower ends of the four support section angle steels 4-1-2 are also respectively provided with support section connecting plates 4-1-5 for connecting the column section 3. The support section connecting plate 4-1-5 can adopt an angle steel structure, which can be connected to the angle steels at the four corners of the column section 3 by flat head bolts, so as to facilitate the rapid disassembly of the column section 3. The length of the column section 3 can be determined according to the height of the underground floor, and the number of column sections 3 used can be determined according to the depth of the foundation pit or the number of underground floors. The upper and lower adjacent column sections 3 can be connected by the support section 4.

[0091] In addition, in the above-mentioned column pile production method, corresponding production equipment needs to be used in each production step, such as steel structure processing equipment, steel cage processing equipment, concrete mixing equipment, and molds and molding equipment, among which the steel structure processing equipment includes angle steel cutting machines, welding robots, drilling machines, etc. These equipment need to be debugged and calibrated to ensure processing accuracy and production efficiency. For example, the length error of the angle steel after cutting should not exceed ±2mm. The steel cage processing equipment includes steel bar bending machines, steel bar cutting machines, welding equipment, etc. These equipment need to be maintained and debugged to ensure the processing quality of the steel cage. For example, the steel bar cutting machine is used to cut the steel bar to the designed length. The end of the steel bar after cutting should be flat and free of burrs, and the length error should be controlled within ±5mm. The concrete mixing equipment needs to be trial-mixed according to the designed mix ratio, and the mixing time and mixing speed are adjusted to meet the performance requirements of high-strength concrete. The molds and molding equipment need to be cleaned, inspected and debugged to ensure the dimensional accuracy and molding quality of the mold.

[0092] After the above-mentioned column pile production is completed, the transportation stage begins. Before transportation, each section of the column pile should be protected to avoid damage to the column pile during transportation; and after the column pile is transported to the construction site, it should be inspected immediately, including the appearance quality, size deviation, fixing condition, etc. After transportation to the construction site, the construction stage begins.

[0093] The following combination Fig.12 , the construction method of the above-mentioned assembled high-strength and toughness composite prefabricated column piles is described in detail.

[0094] The column pile construction method prepared by the production method of an assembled high-strength and toughness composite prefabricated column pile in this embodiment comprises the following steps:

[0095] S1. Equipment debugging: Install the static pile driver according to the construction position of the column pile, and debug the static pile driver to ensure the normal operation of the hydraulic system, electrical system and travel system of the static pile driver; install the pile driver on the static pile driver, and debug the pile driver to ensure that the pile driver can smoothly press the column pile into the designed elevation; remove the pile driver after debugging. It should be noted that before construction, the construction site should be cleaned and leveled to ensure the flatness and stability of the construction site. The construction position of the column pile should be laid out, and the laying accuracy should be controlled within the allowable range. The static pile driver should be selected according to the diameter, length and design bearing capacity of the column pile, and its tonnage should meet the requirements for pressing the column pile, while considering the site conditions of the construction site. When installing the static pile driver, the level and stability of the equipment should be ensured. During the debugging of the static pile driver, a test pressure operation should be carried out to ensure that the equipment's pile pressing force and pile pressing speed meet the design requirements. The pile driver is a key tool for pressing the column pile into the designed elevation. According to the size and shape of the column pile, select a suitable pile driver; the material of the pile driver should have sufficient strength and rigidity to withstand the reaction force during the pile driving process.

[0096] S2. Construction of foundation pile segments: Foundation pile segment 1 is the key part connecting the column pile and the foundation pit bottom plate, and its construction quality directly affects the stability of the column pile. Before the construction of foundation pile segment 1, the installation position of the column pile should be laid out, and the laying accuracy should be controlled within the allowable range. Use a static pile driver to press foundation pile segment 1 into the designed elevation. During the pile driving process, the pile driving speed should be controlled to avoid damage or deflection of the column pile due to excessively fast pile driving speed. The pile driving speed should be controlled at 0.5-1.0 m / min. After the pile driving is completed, check the verticality of foundation pile segment 1, and the verticality deviation of foundation pile segment 1 should be controlled within 0.5%.

[0097] S3, segmented connection and pile driving: First, connect the column segment 3 through the bottom plate segment 2 at the top of the foundation pile segment 1, and use a static pile driver to press the first column segment 3 into the designed elevation; the connection between the foundation pile segment 1 and the bottom plate segment 2 can be welded or mechanically connected, and the connection between the bottom plate segment 2 and the column segment 3 can be bolted, and the firmness and reliability of the connection should be ensured during the connection; then connect the remaining column segments 3 through the support segment 4 in turn, and use a static pile driver to press the column segment 3 into the designed elevation in segments; the pile driving speed of the column segment 3 is controlled at 0.5 to 1.0 m / min. The construction of the support segment 4 should be carried out according to the design requirements of the foundation pit support beam, and the connection between the support segment 4 and the support beam can be made by cast-in-place concrete connection or mechanical connection.

[0098] S4. Pile delivery with pile driver: Install the pile driver on the static pile driver and connect it to the last column section 3. Use the pile driver and the static pile driver to press the last column section 3 into the designed elevation. At this time, the foundation pile section 1 is located in the bottom stratum of the foundation pit, and the column section 3 is located in the foundation pit. During the pile delivery process, the pile delivery speed should be controlled to avoid damage or deflection of the column pile due to excessively fast pile delivery speed. The pile delivery speed is generally controlled at 0.5 to 1.0 m / min. After the pile delivery is completed, check the verticality of the column pile, and the verticality deviation should not exceed 0.5%; measure the pressed depth of the column pile, and the pressed depth should meet the design requirements.

[0099] S5. Connection of foundation pit support beams: After the column piles are driven, the foundation pit soil is excavated, and the support beams are connected to the corresponding support segments 4 layer by layer from top to bottom to support the foundation pit. During construction, the foundation pit soil is excavated layer by layer, and support beams are constructed in each layer in turn to support the foundation pit until the excavation soil reaches the base. When using cast-in-place support beams, the steel bars in the support beams are inserted into the support segment bidirectional steel bar connectors 4-2 of the support segment 4 for connection.

[0100] S6. Construction of the foundation pit floor: After excavating to the bottom of the foundation pit, the construction of the foundation pit floor begins, and the foundation pit floor is connected to the floor section 2; then the main structure in the foundation pit is constructed layer by layer from bottom to top. During construction, the outer water stop plate 2-4 and studs 2-5 are welded on the floor section 2, and the floor is fixed with the studs 2-5, and the steel bars of the floor are inserted into the two-way steel bar connector 2-2 of the floor section for connection.

[0101] The above-mentioned assembled high-strength and toughness composite prefabricated column pile construction method makes the entire construction process simpler and more efficient, with low construction noise and less pollution, and the construction depth is not limited in principle. It can be used for deeper foundation pit support and has a wider range of applications.

[0102] After the construction of the main structure in the foundation pit is completed, the support removal and recovery step S7 is entered. In the support removal and recovery step S7, the column segment 3 is first dismantled, and then the support segment 4 and the support beam are dismantled; the recovered and repaired column segment 3 is designed and reused according to the design requirements of the next project. When using a cast-in-place support beam, a pneumatic crushing device 4-4 is pre-installed in the support segment 4. When dismantling the support, the pneumatic crushing device 4-4 is used to break the support segment 4, which facilitates the rapid dismantling of the cast-in-place support beam, reduces the difficulty of dismantling the support, and improves the efficiency of dismantling the support. During the dismantling process, special dismantling tools should be used to avoid damage to the column segment 3; during dismantling, it should be carried out section by section from top to bottom, and the dismantled column segment 3 should be cleaned and stored in time. During the reuse process, the quality of the column segment 3 should be strictly inspected to ensure that it meets the requirements for reuse.

[0103] The production method and construction method of the assembled high-strength and tough composite prefabricated column pile of the present invention not only have significant technical advantages, but also perform well in terms of economic and environmental benefits. By optimizing the design and construction process, the column pile can significantly reduce the construction cost and reduce the impact on the environment.

[0104] The economic advantages are as follows:

[0105] 1. Reduce material costs: The use of high-strength and high-toughness composite materials reduces the use of traditional materials. For example, by using FRP fiber grids and high-strength concrete, the use of steel and ordinary concrete is reduced, reducing material costs. The recyclable design of the column segment allows the material to be reused many times, further reducing the overall cost of the project. For example, the dismantled column segment can be repaired and reprocessed and used in the next project, reducing material waste.

[0106] 2. Improve construction efficiency: The factory production and on-site assembly construction of prefabricated column piles significantly shorten the construction period. Compared with traditional cast-in-place piles, the construction speed of prefabricated column piles is increased by 30% to 50%, reducing the rental cost of construction equipment and labor costs. The application of intelligent construction equipment and monitoring technology improves construction accuracy and quality, and reduces rework and repair costs during construction.

[0107] 3. Long-term economic benefits: The high strength and high toughness design of the column pile significantly extends its service life under complex geological conditions, reducing the cost of repair and replacement due to pile damage. The recyclable design of the column pile allows the material to be reused many times, reducing the long-term operating costs of the project.

[0108] The environmental benefits are as follows:

[0109] 1. Reduce construction pollution: The factory production of prefabricated column piles reduces noise, dust and wastewater emissions at the construction site. Compared with traditional cast-in-place piles, prefabricated column piles produce almost no mud pollution during construction, reducing damage to the environment. The application of intelligent construction equipment and monitoring technology reduces energy consumption and waste emissions during construction. For example, by optimizing the pile driving force and pile driving speed, the energy consumption of the equipment is reduced.

[0110] 2. Recyclability of materials: The recyclable design of the column piles allows the materials to be reused many times, reducing the generation of construction waste. For example, the column piles after demolition can be repaired and reprocessed and used in the next project, reducing the exploitation of natural resources. The high strength and high toughness design of the column piles make them more durable during use and reduce the waste of materials caused by damage to the pile body.

[0111] 3. Green construction: The design and construction of prefabricated high-strength and tough composite prefabricated column piles fully embodies the concept of green construction. By optimizing the design and construction process, the impact on the environment is reduced, meeting the requirements of sustainable development. The application of intelligent construction and monitoring technology of column piles further improves the environmental protection level of the construction process and provides technical support for green construction.

[0112] In summary, the production method and construction method of the assembled high-strength and toughness composite prefabricated column pile of the present invention is an assembled column pile technology that combines high strength, high toughness, recyclability, connection reliability and intelligent construction, which has significant technical advantages, economic and environmental benefits. By optimizing the design and construction process, the column pile can significantly improve the construction efficiency, reduce the construction cost, and reduce the impact on the environment; effectively solve the problems of the long construction period of traditional column piles, non-recyclable materials, and insufficient connection stiffness, while meeting the requirements of green construction and intelligent construction.

Claims

1. A method for producing assembled high-strength and tough composite prefabricated column piles, characterized in that: The following steps are involved: S1. Column pile design: According to the engineering drawings and related materials, the column pile design drawings are prepared; the column pile includes a foundation pile section (1), a bottom plate section (2), a column section (3) and a support section (4), wherein: The foundation pile section (1) is a prefabricated square pile, comprising a steel cage (1-1), a pile end steel plate welded part (1-2) and square pile concrete (1-3); The bottom plate section (2) comprises a rectangular steel frame (2-1) and bottom plate section concrete (2-3) filled in the rectangular steel frame (2-1); a bottom plate section bidirectional steel bar connector (2-2) for connecting to a steel bar structure in a cast-in-place foundation pit bottom plate in two directions is pre-embedded in the bottom plate section (2); The column section (3) comprises an outer steel structure layer (3-1) and an inner grid structure (3-2) located inside the outer steel structure layer (3-1), and the outer steel structure layer (3-1) and the inner grid structure (3-2) are connected as a whole by pouring high-strength concrete (3-3); The support section (4) comprises a support steel frame (4-1) and support section concrete (4-3) filled in the support steel frame (4-1); a support section bidirectional steel bar connector (4-2) for connecting to a steel bar structure in a cast-in-place support beam in two directions is pre-embedded in the support section (4); S2, prefabricated parts production: according to the column pile design drawings, the pile segment components of the foundation pile segment (1), the bottom plate segment (2), the column segment (3) and the support segment (4) are manufactured respectively; S3, assembly and production: installing the components of each pile segment into the corresponding mold, pouring concrete respectively, and obtaining the prefabricated foundation pile segment (1), bottom plate segment (2), column segment (3) and support segment (4) after solidification.

2. The method for producing assembled high-strength and toughness composite prefabricated column piles according to claim 1 is characterized in that: In step S2, the pile end steel plate welded parts (1-2) of the foundation pile segment (1) include a pile end end plate (1-2-1), a pile end connecting angle steel (1-2-2) and a pile end gusset plate (1-2-3), the four pile end connecting angle steels (1-2-2) are respectively welded and fixed at the four corners of the pile end end plate (1-2-1), and the pile end gusset plate (1-2-3) is welded and fixed between adjacent pile end connecting angle steels (1-2-2); in step S3, a group of pile end steel plate welded parts (1-2) are respectively provided at both ends of the steel cage (1-1), and the manufactured foundation pile segment (1) is one of a prefabricated solid square pile, a prefabricated hollow square pile, a prestressed prefabricated solid square pile and a prestressed prefabricated hollow square pile.

3. The method for producing assembled high-strength and toughness composite prefabricated column piles according to claim 1 is characterized in that: In step S2, the rectangular steel frame (2-1) of the bottom plate segment (2) includes a bottom end plate (2-1-1), a bottom plate segment angle steel (2-1-2), a top end plate (2-1-3) and a bottom plate segment gusset plate (2-1-4), wherein the bottom end plate (2-1-1) and the top end plate (2-1-3) are fixedly connected by four bottom plate segment angle steels (2-1-2), and the four bottom plate segment angle steels (2-1-2) are fixedly connected by bottom plate segment gusset plates (2-1-4) in sequence. The four bottom plate section angle steels (2-1-2) are connected with each other by a plate (2-1-4); the upper and lower ends of the four bottom plate section angle steels (2-1-2) are respectively provided with bottom plate section connecting plates (2-1-6) for connecting the foundation pile section (1) and the column section (3); the inner side of the rectangular steel frame (2-1) is also pre-buried with an inner water stop plate (2-1-5); the outer side of the bottom plate section angle steel (2-1-2) is also welded with an outer water stop plate (2-4) and a plurality of bolts (2-5) for a second time after the foundation pit is excavated.

4. The method for producing assembled high-strength and toughness composite prefabricated column piles according to claim 1 is characterized in that: In step S2, the inner grid structure (3-2) includes an inner fiber grid (3-2-1), a steel grid (3-2-2) and an outer fiber grid (3-2-3), the steel grid (3-2-2) is connected by main bars and stirrups, and the inner fiber grid (3-2-1) and the outer fiber grid (3-2-3) are both made of FRP high-strength fiber mesh; in step S3, the outer fiber grid (3-2-3) is located on the outside of the steel grid (3-2-2), and the inner fiber grid (3-2-1) is located on the inside of the steel grid (3-2-2).

5. The method for producing assembled high-strength and toughness composite prefabricated column piles according to claim 4 is characterized in that: In step S2, the outer steel structure layer (3-1) includes a bottom cover plate (3-1-1), a column section angle steel (3-1-2), a top cover plate (3-1-3), a bottom gusset plate (3-1-4), a top gusset plate (3-1-5) and a middle gusset plate (3-1-6); the bottom cover plate (3-1-1) and the top cover plate (3-1-3) are connected to form a rectangular frame structure through four column section angle steels (3-1-2); the lower ends of the four column section angle steels (3-1-2) are connected in sequence through the bottom gusset plate (3-1-4), and the upper ends are connected in sequence through the top gusset plate (3-1-5); and a plurality of middle gusset plates (3-1-6) are arranged in sequence from top to bottom between the four column section angle steels (3-1-2); in step S3, polypropylene fiber reinforcement material is added to the high-strength concrete (3-3).

6. The method for producing assembled high-strength and toughness composite prefabricated column piles according to claim 4 is characterized in that: In step S3, a foundation pit section monitoring sensor and a wireless communication module are also built into the column section (3), and the foundation pit section monitoring sensor is connected to the background monitoring system through the wireless communication module.

7. The method for producing assembled high-strength and toughness composite prefabricated column piles according to claim 1 is characterized in that: In step S2, a pneumatic fragmentation device (4-4) is further provided in the supporting steel frame (4-1), wherein the pneumatic fragmentation device (4-4) comprises an outer lead pipe (4-4-1) and a cover (4-4-2) detachably mounted at the end of the outer lead pipe (4-4-1), wherein the outer lead pipe (4-4-1) is respectively provided with a liquid carbon dioxide infusion channel (4-4-1a), a positive electrode connecting pipe (4-4-1b) and a negative electrode connecting pipe (4-4-1c); in step S3, the outer lead pipe (4-4-1) is led outward from one side of the supporting section concrete (4-3).

8. The method for producing assembled high-strength and toughness composite prefabricated column piles according to claim 7 is characterized in that: In step S2, the support steel frame (4-1) includes a lower end plate (4-1-1), a support section angle steel (4-1-2), an upper end plate (4-1-3) and a support section gusset plate (4-1-4); the lower end plate (4-1-1) and the upper end plate (4-1-3) are fixedly connected by four support section angle steels (4-1-2); the four support section angle steels (4-1-2) are connected to each other in turn by support section gusset plates (4-1-4); the upper and lower ends of the four support section angle steels (4-1-2) are also respectively provided with support section connecting plates (4-1-5) for connecting the column section (3).

9. A method for constructing column piles prepared by the method for producing assembled high-strength and toughness composite prefabricated column piles according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Equipment debugging: Install the static pile driver according to the construction position of the column pile, and debug the static pile driver to ensure the normal operation of the hydraulic system, electrical system and travel system of the static pile driver; install the pile driver on the static pile driver, and debug the pile driver to ensure that the pile driver can smoothly press the column pile into the designed elevation; After the pile driver is debugged, it is removed; S2. Construction of foundation pile segment: Use a static pile driver to press the foundation pile segment (1) into the designed elevation, control the pile driving speed at 0.5-1.0 m / min, and control the verticality deviation of the foundation pile segment (1) within 0.5%; S3, segmented connection and pile driving: first, the column segment (3) is connected to the top of the foundation pile segment (1) through the bottom plate segment (2), and the first column segment (3) is driven into the designed elevation using a static pile driver; then, the remaining column segments (3) are connected in sequence through the support segment (4), and the column segments (3) are driven into the designed elevation in segments using a static pile driver; the pile driving speed of the column segment (3) is controlled at 0.5 to 1.0 m / min; S4, pile driving with a pile driver: the pile driver is installed on the static pile driver and connected to the last column section (3), and the last column section (3) is pressed into the designed elevation by the pile driver and the static pile driver. At this time, the foundation pile section (1) is located in the base stratum of the foundation pit, and the column section (3) is located in the foundation pit; S5. Connection of foundation pit support beams: after the column piles are driven, the foundation pit soil is excavated, and the support beams are connected to the corresponding support sections (4) layer by layer from top to bottom to support the foundation pit; S6. Construction of foundation pit floor: After excavating to the bottom of the foundation pit, the construction of the foundation pit floor begins, and the foundation pit floor is connected to the floor section (2); then the main structure in the foundation pit is constructed layer by layer from bottom to top.

10. The method for constructing assembled high-strength and toughness composite prefabricated column piles according to claim 9, characterized in that: After the main structure construction in the foundation pit is completed, the support dismantling and recovery step S7 is entered; in the support dismantling and recovery step S7, the column section (3) is first dismantled, and then the support section (4) and the support beam are dismantled; the recovered and repaired column section (3) is designed and reused according to the design requirements of the next project.

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