Green assembly type piled anchor wall collaborative structure and design method and construction method thereof

Abstract

The invention discloses a green assembly type piled anchor wall collaborative structure and a design method and a construction method thereof, the green assembly type piled anchor wall collaborative structure comprises a plurality of slide-resistant piles which are vertically arranged, a counterfort type retaining wall is arranged above the slide-resistant piles, and a retaining wall heel slab at the bottom of the counterfort type retaining wall and the pile tops of the slide-resistant piles are rigidly anchored through an anchoring assembly; the anchor cable penetrates through the counterfort retaining wall and then is embedded into a side slope soil layer, active prestress is applied through tensioning, landslide thrust is shared, and the anchor cable is combined with the slide-resistant piles and the counterfort retaining wall to form a space stress system. The anchor cable prestress value is dynamically optimized through an algorithm, when the maximum value of the pile side stress of the pile-soil contact face exceeds a preset threshold value, dynamic operation is ended, and the optimal anchor cable prestress value and the width of the retaining wall heel slab are checked and determined. The problems that in the construction process of an existing piled anchor wall structure, environment resources are damaged, the construction period is long, and cost is high are solved.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering technology, and relates to a green prefabricated pile-anchor-wall collaborative structure and its design and construction methods. Background Technology

[0002] With the continuous improvement of my country's expressway network, expressway reconstruction and expansion projects have become an important means of improving transportation capacity. Especially in projects expanding from four lanes to six lanes, traditional widening schemes often employ land acquisition and new embankment construction. However, in areas near urban areas, ecological protection zones, or sections with complex property rights, there are often insurmountable constraints such as land acquisition restrictions and land use boundaries. Against this backdrop, how to implement safe and efficient roadbed widening within the slope range has become a key technical challenge restricting project implementation. Therefore, green prefabricated pile-anchor walls, as an important retaining structure, have been widely used in remediation projects due to their advantages such as high stability, small construction space occupation, high economy, and strong adaptability. However, existing structural technologies and calculation methods still have many shortcomings. The main problems are:

[0003] 1. Traditional gravity retaining walls require large-scale excavation, occupy a large area, are prone to damaging slope stability, and have a long construction cycle for cast-in-place concrete, resulting in serious mud pollution. They are difficult to meet the requirements for rapid construction in renovation and expansion projects and cause environmental damage.

[0004] 2. Most existing calculations are based on a single support structure and do not consider the coordinated design stress of multi-structure support systems. They cannot calculate the limit state of stress of multi-structure support systems, which leads to the use of more materials during construction, resulting in material waste and increased costs.

[0005] 3. The single support structure has insufficient anti-sliding capacity and low mechanical efficiency. In addition, the traditional slope protection technology occupies a large area and does not fully consider or directly ignore the resistance of the soil in the passive zone in front of the pile. This results in the pile body having to independently bear all the landslide thrust, which leads to the forced increase in the cross-sectional size of the pile body. This results in a significant increase in the amount of support work or a large increase in the construction land, causing a waste of land resources. Summary of the Invention

[0006] To address the aforementioned issues, this invention provides a green prefabricated pile-anchor-wall collaborative structure, which enhances the overall structural stability and node bearing capacity, providing reliable technical support for engineering implementation under complex geological conditions.

[0007] The second objective of this invention is to provide a design method for a green prefabricated pile-anchor-wall collaborative structure.

[0008] The third objective of this invention is to provide a construction method for a green prefabricated pile-anchor-wall collaborative structure, which solves the problems of environmental and resource damage, long construction period and high cost in the construction of existing pile-anchor-wall structures.

[0009] The technical solution adopted in this invention is a green prefabricated pile-anchor-wall collaborative structure, which includes multiple vertically arranged anti-slide piles. A buttress-type retaining wall is provided above the anti-slide piles. The retaining wall heel plate at the bottom of the buttress-type retaining wall is rigidly anchored to the pile top of the anti-slide pile through an anchoring component.

[0010] After passing through the buttress retaining wall, the anchor cable is embedded in the slope soil layer. Active prestress is applied through tensioning to share the landslide thrust. It forms a spatial force system with the anti-slide pile and the buttress retaining wall.

[0011] Furthermore, the anchoring assembly includes:

[0012] A perforated steel plate is pre-embedded in the top of the anti-slide pile, and bolts are pre-embedded in the holes of the perforated steel plate.

[0013] An embedded steel plate is placed inside the retaining wall heel plate. The embedded steel plate has the same structure as the perforated steel plate.

[0014] When installing a buttress retaining wall, align the holes in the pre-embedded steel plate with the bolts, and apply pre-tightening force by installing nuts to complete the connection of the anchoring components.

[0015] Furthermore, the retaining wall panels, retaining wall buttresses, and retaining wall heel plates of the buttress-type retaining wall are prefabricated in the factory; the steel cage of the anti-slide pile is prefabricated in the factory.

[0016] A green prefabricated pile-anchor-wall collaborative structure design method includes the following steps:

[0017] S1, Establish initial parameters and geometric model;

[0018] S2, the actual tension of the prestressed anchor cable is determined based on the coupled deformation of the anti-slide pile, the buttress retaining wall and the prestressed anchor cable;

[0019] S3, determine the internal forces of the anti-slide pile in the loaded section;

[0020] S4. Based on the subgrade coefficient method, a calculation model is established for pile displacement, pile side stress, and pile internal forces in the anchorage section. The distance from the top of the anchorage section to the point of pile rotation is calculated based on the continuity condition that the internal forces in the loaded section and the anchorage section are equal at the sliding surface. The angle of rotation of a buttress retaining wall under the thrust of a landslide. and the width of the retaining wall heel plate ;

[0021] S5 uses an algorithm to dynamically optimize the prestress value of the anchor cable. When the maximum value of the pile side stress at the pile-soil contact surface exceeds the preset threshold, the dynamic calculation ends, and the optimal prestress value of the anchor cable and the width of the retaining wall heel plate are verified and determined.

[0022] Furthermore, S2 includes the following steps:

[0023] S21, Determine the flexibility coefficient of the prestressed anchor cable. :

[0024]

[0025] in, The length of the free section of the anchor cable; The number of anchor cable bundles per hole; The cross-sectional area of ​​each anchor cable bundle; The elastic modulus of the anchor cable;

[0026] S22, Determine the tensile force generated by the deformation of the prestressed anchor cable. :

[0027]

[0028] in, The distance from the sliding surface to the center of pile rotation. This is the distance from the anchor point to the sliding surface; Indicates the corner of a buttress retaining wall;

[0029] S23, Actual tensile force For prestressed anchor cables Tensile force generated by deformation sum.

[0030] Furthermore, S3 includes the following steps:

[0031] S31, Establish the internal force equations for any cross section of the anti-slide pile under load:

[0032]

[0033]

[0034] in, This indicates the shear force in the loaded section of the anti-slide pile; The distributed load of the anti-slide pile is indicated by a triangular distribution. This indicates the horizontal distributed load on the buttress retaining wall, which is distributed in a rectangular uniform load pattern. This refers to the length of the loaded section of the anti-slide pile; This represents the distance from the top of the pile to any cross-section of the pile body; This indicates the actual tensile force of the prestressed anchor cable; This represents the bending moment of the loaded section of the anti-slide pile (1). This indicates the distance from the anchor point to the sliding surface;

[0035] S32, substitute the actual load-bearing section length of the anti-slide pile into the above formula to calculate the shear force and bending moment of the pile body at the sliding surface.

[0036] Furthermore, S4 includes the following steps:

[0037] S41, Calculation of internal forces in the anchorage section pile body based on the subgrade coefficient method;

[0038]

[0039]

[0040] This represents the shear force of the pile body at any cross section of the anchorage segment of the anti-slide pile. This represents the bending moment of the pile body at any cross section of the anti-slide pile anchorage section; This indicates the calculated width of the anti-slide pile; Indicates the subgrade coefficient at the slip surface; This represents the proportionality coefficient of the subgrade coefficient below the slip surface as it varies with depth. Indicates the corner of a buttress retaining wall; The distance from the sliding surface to the center of pile rotation. This refers to the length of the anchorage section of the anti-slide pile; This indicates the shear force of the pile body at the slip surface; Indicates the bending moment of the pile body at the slip surface;

[0041] S42, Calculate the pile displacement in the anchorage section. :

[0042]

[0043] S43, Calculate the pile side stress in the anchorage section. :

[0044]

[0045] S44, by establishing the equality of shear force and bending moment at the sliding surface in the loaded section and the anchored section, and then establishing the resultant force of the buttress retaining wall. Thus, the solution is obtained. , and .

[0046] Furthermore, S5 includes: determining the maximum value and location of the pile side stress in the anchorage section, calculating the ultimate bearing capacity of the pile side at that location, and determining whether the following condition is met: the maximum value of the pile side stress in the anchorage section ≥ 95% of the ultimate bearing capacity of the pile side. If this condition is not met, the prestress of the prestressed anchor cable is reduced. The dynamic calculation ends when the condition is met.

[0047] A construction method for a green prefabricated pile-anchor-wall collaborative structure includes the following steps:

[0048] Step 1, Anti-slide pile construction: Accurately measure the pile position according to the design, drill the hole, hoist the prefabricated steel cage into the hole, pre-embed the perforated steel plate on the top of the pile and weld it to the steel cage, pour concrete, and after the concrete strength reaches the design requirements, clean the top of the pile to expose the pre-embedded perforated steel plate, and pre-embed bolts in the hole of the perforated steel plate.

[0049] Step 2: Tie the lower layer of steel reinforcement mesh for the retaining wall heel plate, then place the upper layer of steel reinforcement mesh, and then tie the vertical steel reinforcement of the retaining wall panel and retaining wall buttress, and insert them into the retaining wall heel plate; the retaining wall buttress steel reinforcement is firmly connected to the retaining wall panel and retaining wall heel plate steel reinforcement to form an integral skeleton, and the pre-embedded steel plate is installed on the retaining wall heel plate steel reinforcement skeleton; the buttress retaining wall formwork is installed and poured.

[0050] Step 3: Hoist the prefabricated buttress retaining wall as a whole onto the anti-slide pile. Align the holes of the pre-embedded steel plate on the heel plate of the retaining wall with the pre-embedded bolts at the top of the anti-slide pile, insert the bolts, install nuts, and apply pre-tightening force.

[0051] Step 4: Measure and drill the borehole, insert the anchor cable into the borehole, and embed the anchor cable into the slope soil layer; use pure cement grouting, fill the borehole with grout in one go through the grouting pipe until it overflows from the borehole opening; pour a concrete base at the anchor cable borehole opening of the retaining wall, tension and lock it, apply an anti-corrosion layer to the exposed part of the anchor head and the end of the anchor cable, and seal the entire anchor head and concrete base.

[0052] The beneficial effects of this invention are:

[0053] 1. This invention constructs a green prefabricated pile-anchor-wall collaborative structure. Through multiple mechanical interlocking and prestressed collaborative design, the overall stability of the structure and the load-bearing capacity of the nodes are significantly improved, providing a reliable technical guarantee for engineering implementation under complex geological conditions.

[0054] 2. This invention establishes a limit state calculation model for the coordinated stress distribution of piles, anchors, and walls, enabling multiple structures to simultaneously reach their ultimate bearing capacity. In terms of computational theory, based on the internal force calculation equations of rigid anti-slide piles, the prestress parameters of the anchor cables are dynamically optimized through an algorithm. When the maximum value of the pile-soil contact surface stress exceeds 95% of the soil's ultimate bearing capacity threshold, the dynamic calculation ends, and the optimal anchor cable prestress value and retaining wall heel width are checked and locked, achieving the structure's ultimate bearing capacity. This invention, by adopting a coordinated stress distribution mode, breaks through the traditional support structure form, significantly improving anti-slide capacity and achieving the conservation and efficient use of land resources. It overcomes the engineering problems of land resource waste, material redundancy, or insufficient bearing capacity caused by traditional static design paradigms.

[0055] 3. Compared to traditional gravity retaining walls, this invention utilizes a green prefabricated pile-anchor wall structure in a collaborative design, effectively making use of land area even with limited space resources. This maximizes land utilization under safety constraints and avoids the risks associated with large-scale excavation. For cast-in-place concrete retaining walls, the prefabricated structure of this invention allows for rapid assembly and installation, shortening the construction period and meeting the needs of renovation and expansion projects. It also overcomes the dust pollution and wastewater discharge problems associated with cast-in-place concrete curing, aligning with green and environmentally friendly construction principles. Attached Figure Description

[0056] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0057] Figure 1 This is a perspective view of the collaborative design of the green prefabricated pile-anchor wall structure according to an embodiment of the present invention.

[0058] Figure 2 This is a cross-sectional view of the collaborative design of the green prefabricated pile-anchor wall structure according to an embodiment of the present invention.

[0059] Figure 3 This is a diagram of the prestressed anchor cable structure of the green prefabricated pile-anchor wall structure according to an embodiment of the present invention.

[0060] In the diagram, 1. Anti-slide pile, 2. Retaining wall panel, 3. Retaining wall buttress, 4. Retaining wall heel plate, 6. Nut, 7. Embedded steel plate, 8. Bolt, 9. Perforated steel plate, 10. Anchor cable, 11. Anchor head, 12. Concrete base. Detailed Implementation

[0061] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0062] Example 1,

[0063] like Figure 1 As shown, this embodiment of the invention provides a green prefabricated pile-anchor-wall collaborative structure, including multiple anti-slide piles 1 arranged in parallel, a buttress-type retaining wall, and prestressed anchor cables.

[0064] The buttress retaining wall includes a retaining wall panel 2, a retaining wall buttress 3, and a retaining wall heel plate 4;

[0065] The prestressed anchor cable includes an anchor cable 10, a concrete base 12, and an anchor head 11. The anchor cable 10 includes an anchorage section and a free section. The anchorage section and the free section share the same set of steel strands and are physically connected through the continuous extension of the steel strands.

[0066] Construction method for anti-slide pile 1: Based on the design drawings, accurately measure the location of anti-slide pile 1 and set pile position marks. Drill the anti-slide pile 1 mechanically or manually, ensuring the depth and diameter meet design requirements. Prefabricate the reinforcing cage in the factory, ensuring the specifications and spacing of the reinforcing bars meet design requirements. Hoist the prefabricated reinforcing cage into the hole, and pre-embed a perforated steel plate 9 at the top of the anti-slide pile 1. The perforated steel plate 9 must be welded and fixed to the reinforcing cage to ensure accurate positioning. Pour the pile body concrete, requiring layered vibration during pouring to ensure pile quality. After the concrete strength reaches the design requirements, clean the pile top to expose the pre-embedded perforated steel plate 9.

[0067] Buttress retaining walls, such as Figure 2 , 3 As shown, the retaining wall heel plate 4 and the retaining wall pre-embedded system are important components of the collaborative design of green prefabricated pile-anchor wall structure, which can improve the stability of the structure.

[0068] The construction of the buttress retaining wall primarily employs mechanical excavation, supplemented by manual cleaning. The lower layer of reinforcing mesh for the retaining wall heel plate 4 is tied, followed by the upper layer. After the heel plate 4's reinforcing mesh is tied, the vertical reinforcing bars for the retaining wall panel 2 and buttress 3 are tied and inserted into the retaining wall heel plate 4. The buttress 3's reinforcing bars should be firmly connected to the retaining wall panel 2 and heel plate 4's reinforcing bars to form an integral framework. The embedded steel plate 7 is placed on the retaining wall heel plate 4's reinforcing bar framework and welded securely to the main reinforcing bars of the heel plate 4 and buttress 3, ensuring that the embedded steel plate 7 does not shift or tilt during concrete pouring. After welding, damp cotton yarn or foam rods are inserted into the bolt holes of the embedded steel plate 7 and sealed with tape to prevent concrete slurry from flowing into the holes and clogging them. Subsequently, the standardized steel formwork for the vertical and buttress walls is installed, and the buttress retaining wall concrete is poured, compacted using a vibrator. After the concrete pouring is completed, it is immediately covered and watered for curing after initial setting.

[0069] The retaining wall heel plate 4 and the anti-slide pile 1 are connected by an anchoring assembly, which includes a perforated steel plate 9, a bolt 8, a pre-embedded steel plate 7, and a nut 6. The perforated steel plate 9 and the pre-embedded steel plate 7 have the same structure but are located in different positions. The pre-embedded steel plate 7 is inside the retaining wall heel plate 4, while the perforated steel plate 9 is pre-embedded at the top of the anti-slide pile 1.

[0070] like Figure 2As shown, according to the positions of the pre-embedded steel plate 7 and the bolt holes, bolts 8 are pre-embedded at the corresponding positions of the anti-slide pile 1. Then, the buttress retaining wall is hoisted and assembled. The bolts 8 are aligned with the holes of the pre-embedded steel plate 7 of the buttress retaining wall, the nuts 6 are installed, and the pre-tightening force is applied to complete the connection of the anchoring components, forming the retaining wall-pile structure.

[0071] like Figure 3 As shown, the construction method of the prestressed anchor cable system is as follows:

[0072] The first step is to measure and mark the borehole, set up a drilling platform, drill the borehole using the drilling rig, and mechanically send the anchor cable 10 into the hole. The anchor cable 10 is embedded in the slope soil layer, such as the rock layer, which can provide a better bearing layer for prestressing.

[0073] The second step involves using pure cement grouting, filling the hole with grout through the grouting pipe in one go until it overflows from the opening.

[0074] The third step is to build a concrete base 12 formwork at the anchor cable hole of the retaining wall. Before pouring concrete, put the steel bearing plate on the anchor cable 10, make it parallel to the top surface of the concrete base 12 formwork, and fix it firmly. When pouring concrete, it must be vibrated to ensure that it is well connected with the original structure and can reliably transmit the huge tensile force of the anchor cable. Tensioning can only be carried out after curing.

[0075] The fourth step is to install the anchor and jacks, using a graded over-tensioning method. After each level of loading, the elongation of the anchor cable 10 must be measured. After tensioning, the anchor cable 10 is clamped to lock it in place. Excess anchor cable 10 is then cut off. Epoxy resin is applied to the exposed part of the anchor head 11 and the end of the anchor cable 10. C30 fine stone concrete is then used to completely encapsulate the entire anchor head 11 and the concrete base 12, forming a permanent anti-corrosion protective layer.

[0076] By combining anti-slide piles, buttress-type retaining walls, and prestressed anchor cables, the anti-slide and anti-overturning stability of the structure can be significantly improved. This invention provides a green prefabricated anchor pile retaining wall structure that can withstand large landslide thrust, has a fast construction speed, and low cost, effectively addressing the shortcomings of existing technologies and providing a more scientific and efficient solution for landslide control projects.

[0077] Example 2,

[0078] This invention provides a design method for a green prefabricated pile-anchor-wall collaborative structure. The green prefabricated pile-anchor-wall collaborative design includes anti-slide piles 1, buttress-type retaining walls, and prestressed anchor cables 10, as shown below. Figure 1 The anti-slide pile 1 shown is installed at the front edge of the body. The sliding surface near the pile is nearly horizontal, the thickness of the sliding body is 10m, and the area above the sliding surface is severely weathered sandstone and mudstone with a unit weight of [missing information]. The internal friction angle is It lacks cohesion; below the slip surface lies severely weathered mudstone and shale, which can be considered as a relatively dense soil layer, with a unit weight of [missing information]. The internal friction angle is No cohesion. Subgrade coefficient at the slip surface. The proportionality coefficient of subgrade coefficient below slip surface with depth Assume the thrust at that point is... The pile body is made of reinforced concrete (C30). The initial selection of the comprehensive elastic modulus of reinforced concrete is... The pile geometry and layout parameters are as follows: pile length is The loaded section is The anchorage section is The spacing between piles is . The initial prestress of the anchor cable, This represents the actual tension of the anchor cable. The flexibility coefficient of the anchor cable. The rotation angle of the pile. This is the distance from the point of rotation of the pile to the top of the anchorage section. The distance from the anchor point to the sliding surface is given; calculate the internal forces within the anti-slide pile. The strip foundation is 3m long and 2m wide.

[0079] (1) Calculate the ultimate bearing capacity of the buttress retaining wall foundation. Based on the assumption of rigid piles, solve the width L and rotation angle θ of the retaining wall heel plate 4 by combining the foundation bearing capacity formula and the foundation resultant force formula. Calculate the foundation bearing stress according to the rigid pile calculation and the anti-slide pile calculation according to the rigid pile calculation.

[0080] Ultimate bearing capacity of buttress retaining wall foundation :

[0081] (1)

[0082] in, , and This is the bearing capacity coefficient of the foundation, and its value depends on the internal friction angle of the soil. (Referring to a table...) , , ; Cohesive force (no cohesive force in this embodiment); Side load, side load ; For the width of the strip base, This indicates the unit weight of the severely weathered soil layer below the slip surface. .

[0083] Assuming the width of the retaining wall heel plate 4 of the buttress retaining wall is... The height of the buttress retaining wall is The distance from the sliding surface to the rotation center of the anti-slide pile is and corners The corner angles of the buttress retaining wall and the anti-slide piles are the same. .

[0084] Combined force of buttress retaining wall :

[0085] (2)

[0086] in, The foundation reaction coefficient is generally taken as... ; The corner of the retaining wall; It represents a variable in a definite integral.

[0087] Buttress retaining wall foundation resistance moment :

[0088] (3)

[0089] in, Let be the lever arm of the bending moment triangular distribution. .

[0090] Horizontal thrust of buttress retaining wall :

[0091] (4)

[0092] Horizontal distributed load of buttress retaining wall Based on rectangular uniformly distributed load distribution:

[0093] (5)

[0094] This indicates the height of the buttress retaining wall, which is also the load-bearing section. .

[0095] The thrust of each anti-slide pile :

[0096] (6)

[0097] in, For the thrust at the landslide site, Indicates the spacing between piles. .

[0098] Anti-slide pile distributed load Distributed in a triangular pattern:

[0099] (7)

[0100] Ultimate bearing capacity of buttress retaining wall foundation Equal to the resultant force of the foundation :

[0101] (8)

[0102] (2) Anchoring force calculation;

[0103] Assuming the prestress of the anchor cable 20% of the thrust, that is:

[0104] (9)

[0105] In equation (9) The resultant force of the buttress retaining wall is represented.

[0106] Flexibility coefficient :

[0107] (10)

[0108] in, This refers to the length of the free section of the anchor cable; The number of anchor cable bundles per hole; The cross-sectional area of ​​each anchor cable bundle; The elastic modulus of the anchor cable;

[0109] Tensile force generated by deformation :

[0110] (11)

[0111] in, The distance from the sliding surface to the center of pile rotation. This is the distance from the anchor point to the sliding surface; This indicates the angle at which the entire structure rotates after being subjected to the thrust of a landslide (i.e., the angle of rotation of the retaining wall).

[0112] Actual tensile force :

[0113] (12)

[0114] (3) Calculation of internal forces in the loaded section of the pile;

[0115] Shear force of anti-slide pile under load :

[0116] (13)

[0117] This indicates the distributed load on the anti-slide pile. This indicates the horizontally distributed load on the buttress retaining wall.

[0118] Bending moment of the load-bearing section of the anti-slide pile :

[0119] (14)

[0120] This indicates the distance from the anchor point to the sliding surface. .

[0121] This represents the distance from the top of the pile to any cross-section of the pile body, at the slip surface. ,Will Substituting into equations (13) and (14), we obtain the shear force and bending moment of the pile at the slip surface:

[0122] (15)

[0123] (16)

[0124] This indicates the shear force of the pile at the slip surface. This indicates the bending moment of the pile body at the slip surface.

[0125] (4) Shear force of the pile body in the anchorage section at the slip surface and pile bending moment calculate:

[0126] (17)

[0127] (18)

[0128] Indicates the calculated width of the pile ( rice, (Where the width of the strip base is given). This represents the subgrade coefficient at the slip surface. ; This represents the proportionality coefficient of the subgrade coefficient below the slip surface as a function of depth. .

[0129] An equation is established by making the shear force and bending moment equal at the sliding surface in both the loaded section and the anchored section:

[0130] (19)

[0131] (20)

[0132] Solving equations (8), (19), and (20) simultaneously, we get... , , Based on the solved width L of the retaining wall heel plate 4, the construction width of the retaining wall heel plate 4 during construction can be determined. This reduces the use of more materials during construction, thus avoiding material waste and increased costs, while ensuring safety.

[0133] (5) Calculate the pile displacement, pile side stress, pile shear force, and pile bending moment at any cross section of the anchorage section;

[0134] ① Pile body displacement :

[0135] (twenty one)

[0136] ②Pile side stress :

[0137] (twenty two)

[0138] make ,have to This means that the lateral compressive stress is the greatest at that location.

[0139] ③Pile shear force:

[0140] Substituting into the above simultaneous equations, the result is... , , Calculations yielded ;

[0141] (twenty three)

[0142] make ,have to That is, the maximum shear force is at the center of rotation of the pile; let , received the order ; This represents the shear force of the pile body at any cross section of the anchorage segment of the anti-slide pile.

[0143] ④ Bending moment of the pile body:

[0144] Substituting into the above simultaneous equations, the result is... , , Calculations yielded ;

[0145] (twenty four)

[0146] make ,have to That is, at the point where the shear force is zero; This represents the bending moment of the pile body at any cross section of the anti-slide pile anchorage segment.

[0147] The calculation results of pile displacement, internal force and side stress of the anchorage section calculated according to rigid pile are shown in Table 1.

[0148] Table 1 Calculation results of pile displacement, internal force and side stress in the anchorage section (rigid pile)

[0149]

[0150] (6) Foundation strength verification;

[0151] As shown in Table 1, in The maximum value of the pile side stress is taken at the location. ultimate bearing capacity of pile side for:

[0152] (25)

[0153] internal friction angle of severely weathered soil layers below the slip surface ; This indicates the weight of the denser soil layer above the slip surface, due to... If it does not reach the expected 95%, then reduce... The value of , take The calculation steps are the same as above, and the results are shown in Table 2.

[0154] Table 2 Calculation results of pile displacement, internal force and side stress in the anchorage section when the prestress is 12% of the thrust (rigid pile)

[0155]

[0156] At this point, the maximum stress on the pile side is taken at the bottom of the column. At this time, we obtain The requirements are met.

[0157] The calculation results show that by dynamically optimizing the anchor cable prestress value through the algorithm, when the maximum value of the pile side stress at the pile-soil contact surface exceeds 95% of the soil ultimate bearing capacity threshold, the dynamic calculation ends, and the optimal anchor cable prestress value and retaining wall heel plate width are checked and locked to reach the ultimate bearing capacity state of the structure.

[0158] This invention systematically solves the problems of environmental damage, long construction periods, and high costs associated with existing technologies through three core strategies: prefabricated green construction, optimized synergistic stress design, and mechanical connections. By employing a prefabricated structure, the steel cages of the anti-slide piles and the buttress retaining walls (including retaining wall panels, buttresses, and heel plates) are prefabricated in the factory and transported to the site for assembly, achieving green construction. This method avoids the mud pollution, dust, and wastewater discharge caused by traditional cast-in-place concrete construction. Secondly, the optimized structural design reduces land excavation and occupation. This invention adopts a synergistic support system of "anti-slide piles + buttress retaining walls + prestressed anchor cables." Compared to traditional gravity retaining walls, this composite structure occupies less land and has higher stability. It avoids the large-scale excavation required for gravity retaining walls, effectively solving the problem of "wasting land resources." This invention significantly shortens the construction period by transforming on-site operations into factory prefabrication and rapid on-site assembly. This model eliminates the lengthy on-site concrete curing time, enabling rapid construction. This invention effectively controls the total project cost by optimizing the design to save materials and land costs. Material costs can be saved through collaborative design and calculation.

[0159] This invention utilizes an algorithm to dynamically optimize the prestress of anchor cables, enabling the anti-slide piles, retaining walls, and anchor cables to simultaneously reach their ultimate bearing capacity. Traditional single-structure designs are often overly conservative, leading to material redundancy and waste. The collaborative calculation model of this invention can accurately calculate the optimal stress parameters of each component, such as locking the optimal prestress value of the anchor cables and the width of the retaining wall heel plate. This avoids material waste caused by design redundancy, directly reducing the amount of steel reinforcement and concrete used, thereby saving material costs.

[0160] In this embodiment of the invention, the bolted connection between the top of the anti-slide pile and the heel plate is to achieve a rigid collaborative design system between the cantilever anti-slide pile and the buttress retaining wall. This mechanically integrates the anti-slide pile and the buttress retaining wall into a rigid whole, jointly bearing and transmitting enormous horizontal thrust and overturning moment. The connection position directly determines the difference in the structural mechanics model. Based on the rigid connection between the anti-slide pile and the buttress retaining wall, a prestressed anchor cable system is introduced. The anchor cables form a spatial prestressed system through the central duct of the anti-slide pile and the internal channel of the retaining wall, working together with the bolted connection to achieve a performance breakthrough.

[0161] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A green prefabricated pile-anchor-wall collaborative structure, comprising multiple vertically arranged anti-slide piles (1), characterized in that, A buttress wall is provided above the anti-slide pile (1), and the buttress wall heel plate (4) at the bottom of the buttress wall is rigidly anchored to the top of the anti-slide pile (1) through an anchoring component. After passing through the buttress wall, the anchor cable (10) is embedded in the slope soil layer. Active prestress is applied by tensioning to share the landslide thrust. It forms a spatial force system with the anti-slide pile (1) and the buttress wall.

2. The green prefabricated pile-anchor-wall collaborative structure according to claim 1, characterized in that, The anchoring assembly includes: A perforated steel plate (9) is embedded in the top of the anti-slide pile (1), and bolts (8) are embedded in the holes of the perforated steel plate (9). An embedded steel plate (7) is placed inside the retaining wall heel plate (4). The embedded steel plate (7) has the same structure as the perforated steel plate (9). When installing the buttress retaining wall, align the holes of the pre-embedded steel plate (7) with the bolts (8), and apply pre-tightening force by installing the nuts (6) to complete the connection of the anchoring components.

3. The green prefabricated pile-anchor-wall collaborative structure according to claim 1, characterized in that, The retaining wall panel (2), retaining wall buttress (3) and retaining wall heel plate (4) of the buttress-type retaining wall are prefabricated in the factory; the steel cage of the anti-slide pile (1) is prefabricated in the factory.

4. The green prefabricated pile-anchor-wall collaborative structure design method as described in claim 1, characterized in that, Includes the following steps: S1, Establish initial parameters and geometric model; S2, the actual tension of the prestressed anchor cable (10) is determined based on the coupled deformation of the anti-slide pile (1), the buttress retaining wall and the prestressed anchor cable (10); S3, determine the internal forces of the load-bearing section of the anti-slide pile (1); S4. Based on the subgrade coefficient method, a calculation model is established for pile displacement, pile side stress, and pile internal forces in the anchorage section. The distance from the top of the anchorage section to the point of pile rotation is calculated based on the continuity condition that the internal forces in the loaded section and the anchorage section are equal at the sliding surface. The angle of rotation of a buttress retaining wall under the thrust of a landslide. and the width of the retaining wall heel plate ; S5 uses an algorithm to dynamically optimize the prestress value of the anchor cable. When the maximum value of the pile side stress at the pile-soil contact surface exceeds the preset threshold, the dynamic calculation ends, and the optimal prestress value of the anchor cable and the width of the retaining wall heel plate are verified and determined.

5. The green prefabricated pile-anchor-wall collaborative structure design method according to claim 4, characterized in that, S2 includes the following steps: S21, Determine the flexibility coefficient of the prestressed anchor cable (10). : （1） in, The length of the free section of the anchor cable; The number of anchor cables per hole; The cross-sectional area of ​​each anchor cable bundle; The elastic modulus of the anchor cable; S22, Determine the tensile force generated by the deformation of the prestressed anchor cable (10). : （2） in, The distance from the sliding surface to the center of pile rotation. This is the distance from the anchor point to the sliding surface; Indicates the corner of a buttress retaining wall; S23, Actual tensile force For the prestressing of the prestressed anchor cable (10) Tensile force generated by deformation sum.

6. The green prefabricated pile-anchor-wall collaborative structure design method according to claim 4, characterized in that, S3 includes the following steps: S31, Establish the internal force equations for any section of the load-bearing segment of the anti-slide pile (1): （3） （4） in, This represents the shear force of the loaded section of the anti-slide pile (1); The distributed load of the anti-slide pile (1) is shown to be distributed in a triangular pattern. This indicates the horizontal distributed load on the buttress retaining wall, which is distributed in a rectangular uniform load pattern. The length of the loaded section of the anti-slide pile (1); This represents the distance from the top of the pile to any cross-section of the pile body; This indicates the actual tension of the prestressed anchor cable (10); This represents the bending moment of the loaded section of the anti-slide pile (1). This indicates the distance from the anchor point to the sliding surface; S32, substitute the actual load-bearing section length of the anti-slide pile (1) into equations (3) and (4) to calculate the shear force and bending moment of the pile body at the sliding surface.

7. The green prefabricated pile-anchor-wall collaborative structure design method according to claim 6, characterized in that, S4 includes the following steps: S41, Calculation of internal forces in the anchorage section pile body based on the subgrade coefficient method; （5） （6） This represents the shear force of the pile body at any cross section of the anchorage segment of the anti-slide pile (1). The bending moment of the pile body at any cross section of the anchorage section of the anti-slide pile (1) is represented; This indicates the calculated width of the anti-slide pile (1); Indicates the subgrade coefficient at the slip surface; This represents the proportionality coefficient of the subgrade coefficient below the slip surface as it varies with depth. Indicates the corner of a buttress retaining wall; The distance from the sliding surface to the center of pile rotation. The length of the anchorage section of the anti-slide pile (1) is given. This indicates the shear force of the pile body at the slip surface; Indicates the bending moment of the pile body at the slip surface; S42, Calculate the pile displacement in the anchorage section. : （7） S43, Calculate the pile side stress in the anchorage section. : （8） S44, by establishing the equality of shear force and bending moment at the sliding surface in the loaded section and the anchored section, and then establishing the resultant force of the buttress retaining wall. Thus, the solution is obtained. , and .

8. The green prefabricated pile-anchor wall collaborative structure design method according to claim 7, characterized in that, S5 includes: determining the maximum value and location of the pile side stress in the anchorage section, calculating the ultimate bearing capacity of the pile side at the location, and determining whether the following condition is met: the maximum value of the pile side stress in the anchorage section is ≥ 95% of the ultimate bearing capacity of the pile side. If not, the prestress of the prestressed anchor cable (10) is reduced. The dynamic calculation ends when the condition is met.

9. The construction method of the green prefabricated pile-anchor-wall collaborative structure as described in claim 1, characterized in that, Includes the following steps: Step 1, Anti-slide pile (1) construction: Accurately measure the pile position according to the design, drill the hole, hoist the prefabricated steel cage into the hole, pre-embed the perforated steel plate (9) on the top of the pile and weld it to the steel cage, pour concrete, and after the concrete strength reaches the design requirements, clean the top of the pile to expose the pre-embedded perforated steel plate (9), and pre-embed bolts (8) in the hole position of the perforated steel plate (9). Step 2: Tie the lower layer of steel mesh for the retaining wall heel plate (4), then place the upper layer of steel mesh, and then tie the vertical steel bars of the retaining wall panel (2) and the retaining wall buttress (3) and insert them into the retaining wall heel plate (4); the steel bars of the retaining wall buttress (3) are firmly connected with the steel bars of the retaining wall panel (2) and the retaining wall heel plate (4) to form an integral skeleton, and the embedded steel plate (7) is installed on the steel bar skeleton of the retaining wall heel plate (4); the buttress type retaining wall formwork is installed and poured; Step 3: hoist the prefabricated buttress retaining wall as a whole above the anti-slide pile (1), align the holes of the pre-embedded steel plate (7) on the retaining wall heel plate (4) with the pre-embedded bolts (8) at the top of the anti-slide pile (1), insert the bolts, install the nuts (6), and apply the pre-tightening force; Step 4: Measure and drill the hole, insert the anchor cable (10) into the hole, and embed the anchor cable (10) into the slope soil layer; use pure cement grouting, fill the hole with grout through the grouting pipe in one go until the hole overflows; pour concrete base (12) at the anchor cable hole of the retaining wall, tension and lock, apply anti-corrosion layer to the exposed part of the anchor head (11) and the end of the anchor cable (10), and seal the entire anchor head (11) and concrete base (12).

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