Method and system for calculating soil pressure of foundation pit support structure under bilateral coupling deformation

Abstract

The invention relates to the technical field of foundation pit engineering, and discloses a foundation pit enclosure structure soil pressure calculation method and system under bilateral coupling deformation, and the method comprises the steps: obtaining deformation correlation parameters of an enclosure structure of a target foundation pit; initial deformation fitting is conducted on the enclosure structure, active and passive initial soil pressure of the enclosure structure is obtained, and the initial soil pressure is associated with the embedding depth of the enclosure structure; the deformation correlation parameters and the initial soil pressure are input into the bilateral coupling deformation calculation model, and horizontal deformation of the two sides of the enclosure structure is obtained; inputting the horizontal deformation of the two sides into a non-limit soil pressure calculation model to obtain the soil pressure of the enclosure structure; and if the horizontal deformation on the two sides and the soil pressure do not meet the convergence requirement, inputting the soil pressure into the bilateral coupling deformation calculation model for iteration. According to the method, the stress conditions of the two sides of the enclosure structures can be considered, so that the mutual influence of stress between the enclosure structures on the two sides is coupled.

Description

Technical Field

[0001] The invention relates to the technical field of foundation pit engineering, and in particular to a method and system for calculating earth pressure of a foundation pit retaining structure under bilateral coupling deformation. Background Art

[0002] When designing the strength of the foundation pit retaining structure, it is necessary to calculate the bending moment and shear stress of the retaining structure, and then arrange the reinforcement according to the concrete design principle. The external force on the foundation pit retaining structure is mainly the soil pressure on both sides. The traditional calculation method of the soil pressure on the foundation pit retaining structure is to assume that the soil pressure on the inner side of the foundation pit excavation is the ultimate active soil pressure and the soil pressure on the outer side of the foundation pit excavation is the ultimate passive soil pressure. In almost all working conditions, since the foundation pit retaining structure itself has a deformation limit, which is less than the ultimate displacement required by the foundation pit retaining structure to make the soil behind the wall reach the ultimate state, the soil pressure behind the wall is often between the static soil pressure and the ultimate soil pressure. The specification points out that the soil pressure on both sides of the retaining wall is designed according to the ultimate soil pressure, which is obviously not in line with the actual situation. The latest research on non-ultimate soil pressure often considers the wall as a rigid body, which makes the analysis of the soil pressure at a certain depth of the retaining wall have a large error. Therefore, a calculation method that can consider the soil pressure on the retaining wall under the flexible deformation of the foundation pit retaining structure is needed to further improve the calculation accuracy.

[0003] After horizontal supports are installed on the retaining walls on both sides of the foundation pit retaining structure, the retaining walls and horizontal supports on both sides can share and transmit horizontal forces, so that the retaining walls and horizontal supports constitute a force system. When the foundation pit project is subjected to unbalanced loads, the unbalanced horizontal forces on both sides of the foundation pit will affect each other and reach a new balance, and the actual force on the horizontal support is more different from when the mutual influence is not considered. However, the current specifications and main design methods consider the stress conditions on both sides of the foundation pit retaining structure separately, and cannot couple the mutual influence of the forces between the retaining structures on both sides. In order to more accurately describe the overall stress state of the foundation pit retaining structure system, to cope with the challenges brought by unbalanced loads to the foundation pit retaining structure design, and to improve the efficiency and safety of structural design, a better bilateral coupling overall calculation method is needed. Summary of the invention

[0004] Based on this, the present application proposes a method and system for calculating the earth pressure of foundation pit retaining structure under bilateral coupling deformation, aiming to solve the problem that the current design methods of foundation pit retaining structure only consider the stress conditions on both sides of the retaining structure separately, and cannot couple the mutual influence of the forces between the retaining structures on both sides.

[0005] A first aspect of the present application provides a method for calculating earth pressure of a foundation pit retaining structure under bilateral coupling deformation, the method comprising: Obtaining deformation correlation parameters of the retaining structure of the target foundation pit; Performing initial deformation fitting on the enclosure structure to obtain active and passive initial earth pressures of the enclosure structure, wherein the initial earth pressures are associated with the buried depth of the enclosure structure; Inputting the deformation association parameter and the initial earth pressure into a bilateral coupling deformation calculation model to obtain horizontal deformations on both sides of the retaining structure; Input the horizontal deformations on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the retaining structure; If the horizontal deformation on both sides and the soil pressure do not meet the convergence requirements, the soil pressure is input into the bilateral coupling deformation calculation model for iteration.

[0006] As an optional implementation of the first aspect, the step of performing initial deformation fitting on the retaining structure to obtain the active and passive initial earth pressures of the retaining structure includes: performing initial deformation fitting on the retaining structure using a complete function high-order polynomial, wherein the function expression of the complete function high-order polynomial is: ,in, represents the deformation function of the preliminary fitting of the enclosure structure, z represents the buried depth of the enclosure structure, Represents the unknown coefficient parameters of the enclosure structure.

[0007] As an optional implementation of the first aspect, in the step of inputting the deformation association parameter and the initial earth pressure into the bilateral coupling deformation calculation model to obtain the horizontal deformation on both sides of the retaining structure: a deformation coordination condition is selected as the bilateral coupling deformation calculation model, wherein the function expression of the deformation coordination condition is: ,in, is the support stiffness, is the deformation of the left and right sides of the enclosure structure. To support internal strength.

[0008] As an optional implementation of the first aspect, in the step of inputting the horizontal deformations on both sides into the non-limit earth pressure calculation model to obtain the earth pressure of the retaining structure: the earth pressure includes the non-limit lateral pressure of the soil on both sides of the retaining structure, and the function expression of the non-limit lateral pressure of the soil on one side of the active earth pressure zone is: , the functional expression of the non-limit lateral pressure of the soil on one side of the passive earth pressure zone is: ,in, represents the non-limiting lateral pressure; Indicates the soil volume that changes with the buried depth or soil layer of the retaining structure; It indicates the displacement change of the enclosure structure, that is, the horizontal deformation on both sides of the enclosure structure; It represents the earth pressure coefficient that changes with the displacement of the retaining structure and varies between the active limit and the passive limit. Evolution; It indicates the additional stress in the soil caused by ground overload or dynamic load. represents the equivalent load of soil reinforcement at the bottom of the foundation pit; based on a simple linear assumption, exist Interpolate between: ,in, represents the static earth pressure coefficient, represents the slope of the earth pressure fitting curve; if As it increases outward, the soil develops in the active direction. The value gradually decreases to On the contrary, the soil mass increases in the passive direction to .

[0009] As an optional implementation of the first aspect, the step of inputting the horizontal deformation on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the retaining structure also includes: if there are multiple layers of soil around the retaining structure, updating the soil capacity and earth pressure coefficient of each layer of soil, wherein the multi-layer earth pressure calculation process is: identifying the boundaries and characteristic parameters of each layer of soil around the retaining structure to calculate the earth pressure of each layer of soil; superimposing the earth pressure of each layer of soil to obtain the overall multi-layer earth pressure.

[0010] As an optional implementation manner of the first aspect, the step of inputting the deformation association parameters and the initial soil pressure into the bilateral coupling deformation calculation model to obtain the horizontal deformation on both sides of the retaining structure also includes: if there are discrete deformation points in the distribution of the horizontal deformation on both sides, fitting the discrete deformation points to obtain a first continuous function of the buried depth of the retaining structure and the horizontal deformation on both sides, and using the first continuous function as the distribution function of the horizontal deformation on the left and right sides.

[0011] As an optional implementation of the first aspect, the step of inputting the horizontal deformations on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the retaining structure also includes: if there are discrete stress points in the distribution of the earth pressure, fitting the discrete stress points to obtain a second continuous function of the burial depth of the retaining structure and the earth pressure, and using the second continuous function as the distribution function of the earth pressure.

[0012] As an optional implementation of the first aspect, if the horizontal deformation on both sides and the soil pressure do not meet the convergence requirements, the soil pressure is input into the bilateral coupling deformation calculation model for iteration, and the convergence requirements of the iteration are: ,in, and For the i The horizontal deformation and earth pressure on both sides of the retaining structure are calculated in the second iteration. and For the The horizontal deformation and earth pressure on both sides of the retaining structure are calculated in the second iteration. is the convergence accuracy.

[0013] A second aspect of the present application provides a system for calculating earth pressure of a foundation pit retaining structure under bilateral coupling deformation, the system comprising: A data acquisition module is used to acquire deformation correlation parameters of the retaining structure of the target foundation pit; A preliminary fitting module is used to perform initial deformation fitting on the enclosure structure to obtain active and passive initial earth pressures of the enclosure structure, wherein the initial earth pressures are associated with the buried depth of the enclosure structure; A deformation prediction module, used for inputting the deformation association parameter and the initial earth pressure into a bilateral coupling deformation calculation model to obtain horizontal deformations on both sides of the enclosure structure; An earth pressure prediction module is used to input the horizontal deformations on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the enclosure structure; The iterative convergence module is used to input the soil pressure into the bilateral coupling deformation calculation model for iteration if the horizontal deformation on both sides and the soil pressure do not meet the convergence requirements.

[0014] The third aspect of the present application provides an electronic device, comprising: a processor; a memory for storing executable instructions of the processor; wherein the processor is configured to execute the executable instructions to implement the above-mentioned method for calculating the earth pressure of a foundation pit retaining structure under bilateral coupling deformation.

[0015] The fourth aspect of the present application provides a computer-readable storage medium. When the instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to execute the above-mentioned method for calculating the earth pressure of a foundation pit retaining structure under bilateral coupling deformation.

[0016] Compared with the prior art, the present application provides a method for calculating the earth pressure of a foundation pit retaining structure under bilateral coupled deformation: first, by obtaining the deformation calculation associated parameters of the target foundation pit retaining structure, key information such as the geometric dimensions, soil layer parameters, and load conditions of the foundation pit retaining structure can be obtained, laying the foundation for subsequent calculations; then, the initial deformation fitting is performed on the target foundation pit retaining structure to obtain the distribution function of the preliminary active and passive earth pressures that change with the burial depth of the retaining structure. This step is based on the principles of structural mechanics and soil mechanics. By analyzing the actual deformation data, a mathematical model is established to describe the changing law of earth pressure, making the calculation closer to the actual situation; then, the deformation calculation associated parameters and the initial earth pressure are input into the bilateral coupled deformation. In the edge-coupled deformation calculation model, the distribution of horizontal deformations on both sides is simulated. This model can take into account the influence of the interaction between the soil on both sides of the foundation pit to improve the calculation accuracy; next, the obtained horizontal deformations on both sides are input into the non-limit earth pressure calculation model to further calculate the distribution of earth pressure. This non-limit earth pressure model takes into account the plastic deformation and shear characteristics of the soil, making the calculation results more consistent with the actual soil behavior; finally, if the calculation results do not meet the convergence requirements (that is, the calculation results are not stable), the earth pressure will be fed back to the bilateral coupling deformation calculation model for iteration until the distribution of horizontal deformations on both sides and the distribution of earth pressure reach a convergence state. Such an iterative process ensures the stability and reliability of the calculation results.

[0017] Additional aspects and advantages of the present application will be given in part in the following description, and in part will become apparent from the following description, or will be understood through the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A flow chart of a method for calculating earth pressure of a foundation pit retaining structure under bilateral coupling deformation proposed in the first embodiment of the present application; Figure 2 A soil layer distribution diagram of the foundation pit retaining structure in the second embodiment of the present application; Figure 3 It is a deformation curve diagram of the foundation pit retaining wall in the second embodiment of the present application; Figure 4 The distribution diagram of the soil pressure outside the foundation pit on the double-sided retaining piles in the second embodiment of the present application; Figure 5 The distribution diagram of the soil pressure inside the foundation pit on the double-sided retaining piles in the second embodiment of the present application; Figure 6 This is a schematic structural diagram of a system for calculating earth pressure of a foundation pit retaining structure under bilateral coupling deformation proposed in the third embodiment of the present application.

[0019] The following specific implementation methods will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0021] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here. In addition, the "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally represents that the objects associated with each other are in an "or" relationship.

[0022] In order to facilitate understanding of the main connotation of bilateral coupling in this application, it is explained as follows: In many deep foundation pit projects, double-sided retaining structures (or multiple rows of retaining piles, double rows of piles, etc.) are arranged. In order to ensure the overall stability of the foundation pit and reduce the deformation of the retaining wall, horizontal supports (also called "horizontal tie beams" or "connecting beams") are often set at appropriate locations to connect the left retaining wall with the right retaining wall in the horizontal direction, so that the deformations on both sides affect and restrict each other.

[0023] Left retaining wall: Its horizontal displacement function is: ; Right retaining wall: Its horizontal displacement function is ; Support location: If the support is located at a certain depth (or there are multiple layers of supports, each located at several depths), then at that depth, the displacements of the left and right walls will usually be coupled (i.e. affect each other) through the supports.

[0024] The core point of bilateral coupling is that when the left or right retaining structure is deformed due to soil pressure or other external loads, the support will partially transfer this deformation to the other side, so that the deformation of the left and right retaining structures is not independently distributed, but is linked to the same one or more horizontal supports. They must be solved jointly to obtain more accurate soil deformation and internal force results.

[0025] In order to illustrate the technical solution described in this application, a specific embodiment is provided below for illustration.

[0026] Example 1 See also Figure 1, which is a flow chart of a method for calculating soil pressure of foundation pit retaining structure under bilateral coupling deformation proposed in the first embodiment of the present application. The proposed method includes S01 to S05, which are specifically as follows.

[0027] S01: Obtain the deformation association parameters of the retaining structure of the target foundation pit.

[0028] It should be noted that deformation association parameters are the basis and premise for deformation calculation of foundation pit retaining structure, and cover the necessary information required before importing subsequent models. Usually include but are not limited to the following: 1. Design dimensions of the foundation pit project itself, such as: length, width, excavation depth, excavation layers, etc.; 2. Design dimensions of the retaining structure, such as: thickness of the retaining wall, pile length, pile diameter, support system layout parameters, etc.; 3. Geological parameters, such as: soil layer distribution, soil physical and mechanical parameters (density, cohesion, internal friction angle, elastic modulus, permeability coefficient, etc.), and groundwater level depth and changes; 4. Surrounding environmental loads and construction management plans, such as: overload loads, vehicle dynamic loads, foundation loads of adjacent buildings, and construction stage division; 5. Construction stage and working condition information, such as: excavation progress, support removal and replacement sequence, precipitation measures, monitoring frequency and requirements, etc.

[0029] Understandably, based on engineering design data, geological survey reports, construction management plans and other information, the associated parameters required for the deformation calculation of the foundation pit retaining structure are obtained and sorted out. The associated parameter set includes the physical and mechanical properties of the soil layer, the stiffness of the retaining structure, the characteristics of the support system, the change of the groundwater level and the construction conditions, laying an accurate input foundation for subsequent calculations.

[0030] S02: Perform initial deformation fitting on the retaining structure to obtain the active and passive initial earth pressures of the retaining structure. The initial earth pressure is related to the buried depth of the retaining structure.

[0031] In this step, the deformation or soil pressure of the retaining structure is pre-assumed. The initial deformation curve of the retaining structure can be fitted by a complete function or other numerical methods, and the distribution function of the active soil pressure and passive soil pressure along the depth under the current deformation can be output. This distribution function will be further used as the input condition of the subsequent bilateral coupling deformation calculation model or non-limit soil pressure calculation model.

[0032] It should be noted that in the process of initial deformation fitting of the target foundation pit retaining structure, there will be some discrete points. Therefore, it is necessary to use a complete function or other methods to fit these discrete points to obtain a continuously distributed fitting curve function. The common methods for fitting discrete points are as follows: 1. Complete function high-order polynomial fitting: ,in, represents the deformation function of the preliminary fitting of the enclosure structure, z represents the buried depth of the enclosure structure, Indicates the unknown coefficient parameters of the enclosure structure; 2. Complete function trigonometric function series fitting: ,in, and They represent the unknown coefficients that control the amplitudes of the sine function and the cosine function, and T is a trial function that is generally taken as the length of the retaining pile l; 3. Series fitting of the complete function S-curve: , where L is the proportion of the undetermined coefficient controlling the fitting equation, is the unknown coefficient of each series term, Indicates the calculated depth of the retaining pile from the top of the pile. Here, the top of the retaining pile is flush with the ground. ; 4. Artificial intelligence methods are used to regress or interpolate discrete data.

[0033] S03: Input the deformation association parameters and initial soil pressure into the bilateral coupling deformation calculation model to obtain the horizontal deformation on both sides of the retaining structure.

[0034] It should be noted that the bilateral coupling deformation calculation model is used to comprehensively consider the bilateral soil loads and the connection between the support system and the retaining structure, and output the deformation and internal force distribution of the retaining structure under various construction conditions. The core point is to simultaneously consider the mutual influence of the force and deformation of the retaining structures on the left and right sides. According to different engineering requirements and technical conditions, the bilateral coupling deformation calculation model includes but is not limited to the following forms: 1. Formula-based theoretical model, such as the deformation calculation model described in CN116383949A; 2. Deformation coordination conditions, such as: the deformation of the foundation pit retaining structure meets the continuity condition at the horizontal support depth: ,in, is the support stiffness, is the deformation of the left and right sides of the enclosure structure. To support internal forces; 3. Numerical calculation models, for example: based on finite element (ANSYS, ABAQUS, PLAXIS, etc.) or discrete element (FLAC, PFC, etc.) software, numerical simulation of the retaining structure and surrounding soil is carried out to comprehensively solve the bilateral force and deformation of the retaining structure; 4. Artificial intelligence / machine learning models, for example: using neural networks, gray prediction or decision trees and other methods, based on a large number of historical engineering cases and real-time monitoring data, a model that can predict the deformation of the retaining structure at different construction stages is trained.

[0035] In some embodiments, if there are discrete deformation points in the distribution of the horizontal deformation on both sides, the discrete deformation points are fitted to obtain a first continuous function of the buried depth of the enclosure structure and the horizontal deformation on both sides. , the first continuous function As the horizontal deformation distribution on the left and right sides, the discrete deformation point fitting method can select any complete function for fitting in the preliminary deformation fitting in step S02.

[0036] In this step, a bilateral coupling deformation calculation model that can realize the foundation pit retaining structure is selected or constructed. This model is based on the overall force analysis of the retaining structure, comprehensively considers the horizontal load and flexible deformation characteristics of the soil on the left and right sides, and combines the aforementioned deformation calculation associated parameters to simultaneously solve the deformation of the left and right retaining structures in one or more iterations. Through this bilateral coupling method, the mechanical equilibrium state of the soil-retaining structure interaction in different deformation stages can be truly reflected.

[0037] S04: Input the horizontal deformations on both sides into the non-limit earth pressure calculation model to obtain the earth pressure of the retaining structure.

[0038] The concept of non-limit earth pressure can be understood as follows: In the traditional Coulomb or Rankine theory, the soil pressure is simplified only in the active limit or passive limit state. In fact, in the actual construction and service process of the retaining structure, the soil is generally in a non-limit state, and the earth pressure value is It will be between active and static, passive and static as the displacement of the enclosure structure changes. The expression of the pressure value is: ,in, It is the earth pressure coefficient related to soil displacement and can be described by layers, zones or experimental regression curves.

[0039] It should be further explained that the soil pressure stress distribution in the present application includes the non-limit lateral pressure of the soil on both sides of the target retaining structure, wherein the functional expression of the non-limit lateral pressure of the soil on either side is: ,in, represents the non-limiting lateral pressure; Indicates the soil volume that changes with the buried depth or soil layer of the retaining structure; It indicates the displacement change of the enclosure structure, that is, the horizontal deformation on both sides of the enclosure structure; It represents the earth pressure coefficient that changes with the displacement of the retaining structure and varies between the active limit and the passive limit. Evolution; represents the additional stress generated in the soil by ground overload or dynamic load; based on a simple linear assumption, exist Interpolate between: ,in, represents the static earth pressure coefficient, represents the slope of the earth pressure fitting curve, , is the ultimate displacement of active earth pressure, is the ultimate displacement of active earth pressure, represents the deformation of the enclosure structure; if As it increases outward, the soil develops in the active direction. The value gradually decreases to On the contrary, the soil mass increases in the passive direction to .

[0040] Furthermore, if there are discrete stress points in the distribution of soil pressure, the discrete stress points are fitted to obtain the second continuous function of the buried depth of the retaining structure and the soil pressure stress: , the second continuous function As the distribution function of soil pressure, the discrete stress point fitting method can select any complete function in the preliminary deformation fitting in step S02 for fitting.

[0041] In this step, a calculation model that can be used to calculate non-limit earth pressure is determined based on the actual conditions of the project site. This model can directly or through fitting, use discrete retaining pile earth pressure calculation points to form an earth pressure distribution curve that varies with depth. Unlike the traditional limit earth pressure method, this model does not need to forcibly divide the soil into active or passive limit states, but can dynamically adjust the size and distribution of the corresponding earth pressure with the different degrees of deformation of the retaining structure.

[0042] In some embodiments, it is also necessary to consider that if there are multiple layers of soil around the retaining structure, the soil capacity and soil pressure coefficient of each layer of soil are updated, wherein the multi-layer soil pressure calculation process is: identifying the boundaries and characteristic parameters of each layer of soil around the retaining structure to calculate the soil pressure of each layer of soil; superimposing the soil pressure of each layer of soil to obtain the overall multi-layer soil pressure.

[0043] Specifically, calculate the soil pressure of each layer first. This implementation case involves two soil layers: ,in, Indicates the weight of the first soil layer. Indicates the weight of the second soil layer. Indicates the upper height is , the lower height is The depth interval of the first soil layer is Indicates the upper height is , the lower height is The depth interval of the second soil layer; Calculate the layered earth pressure by combining the non-limit earth pressure formula: The core steps of the multi-layer earth pressure calculation model include: identifying the boundaries of soil layers and characteristic parameters (such as bulk density, internal friction angle, and cohesion); calculating the distribution of earth pressure in each layer separately; and superimposing them layer by layer to obtain the distribution of the overall earth pressure. Therefore, the calculation formula for multi-layer earth pressure is: .

[0044] S05: If the horizontal deformation and soil pressure on both sides do not meet the convergence requirements, the soil pressure is input into the bilateral coupling deformation calculation model for iteration.

[0045] During the iteration process, the deformation calculation associated parameters and soil pressure are input into the bilateral coupling deformation calculation model to obtain the deformation of the left and right retaining structures. and , and then the deformation and Substitute it into the non-limit earth pressure calculation model or the generated earth pressure distribution function to update and obtain an earth pressure distribution closer to the actual working condition. In this process, if the horizontal deformation and earth pressure on both sides have not converged, multiple iterations are required until the calculation results of the horizontal deformation and earth pressure on both sides are balanced or meet the engineering accuracy requirements.

[0046] Iteration through the bilateral coupling deformation calculation model and the non-limit earth pressure calculation model is one of the key points of this implementation method. The specific iterative process and implementation flow can be found as follows: 1. Initial parameters and model preparation: Collect and organize the geometry, soil and load parameters of the foundation pit project as deformation calculation related parameters A, and select or build a bilateral coupling deformation calculation model B and a non-limit earth pressure calculation model C.

[0047] 2. Initial earth pressure and deformation assumptions: If model B or model C requires the distribution of initial earth pressure or the distribution curve of initial deformation, a preliminary fit can be performed through the traditional active-passive earth pressure hypothesis or the corresponding complete function to obtain the distribution function D of earth pressure as the initial input.

[0048] 3. Deformation calculation: Input parameter A and the distribution function D of the initial earth pressure into model B, calculate the deformation curve (or discrete deformation points) of the retaining structure, and obtain the horizontal deformation results on both sides of the retaining structure and .

[0049] 4. Soil pressure update The horizontal deformation results on both sides of the above-mentioned enclosure structure are and Input into the non-limit earth pressure calculation model C to update and obtain the distribution of earth pressure that is closer to the actual stress state.

[0050] 5. Iterate until convergence The updated earth pressure is fed back to model B again, the deformation calculation is repeated and the new deformation value is output; if the iteration between earth pressure and retaining structure deformation has converged or meets the design and monitoring requirements, the calculation ends; otherwise, the iteration continues until the result is stable; where the iteration convergence condition is: ,in, and For the i The horizontal deformation and earth pressure on both sides of the retaining structure are calculated in the second iteration. and For the The horizontal deformation and earth pressure on both sides of the retaining structure are calculated in the second iteration. is the convergence accuracy.

[0051] 6. Result output and application Finally, the deformation curve (or discrete points) and internal force distribution of the retaining structure are obtained, which are used to evaluate the safety and construction risk of the foundation pit project. In actual projects, the model can also be modified or verified in combination with monitoring data to ensure that the calculation results are consistent with the construction process.

[0052] In summary, compared with the prior art, the implementation method of the present application has the following advantages: 1. More realistic mechanical reflection: By simultaneously considering bilateral coupling and non-limit earth pressure, the present invention can more accurately capture the real stress and deformation laws of the retaining structure during the construction process, and reduce the distortion or deviation caused by relying solely on the limit earth pressure calculation.

[0053] 2. Wide applicability: The present invention can adapt to various working conditions such as deep foundation pits, soft soil layers, high water levels, and complex surrounding loads. At the same time, the form of the bilateral coupling deformation calculation model can flexibly select theoretical analysis, numerical simulation or artificial intelligence methods to meet the diverse needs of engineering applications.

[0054] 3. Iterative precision control: Gradually approaching the actual working conditions through multiple iterations helps to control the construction risks of the enclosure structure, reduce the negative impact of deformation on the surrounding environment, and improve project safety and economic benefits.

[0055] 4. It can be effectively combined with measured data: If measured data is obtained during the implementation of the project, it can be fed back into the calculation process of this method to continuously update the soil pressure and retaining structure deformation prediction model to achieve dynamic monitoring and refined control of foundation pit construction.

[0056] Example 2 The foundation pit area of ​​a building is about 6200m 2, one of the cross sections is selected for analysis. The excavation depth of the selected analysis section is 12.2m and the width is 50m. The retaining wall is 800mm thick and the insertion depth is 26m. The structural beam slab is used as the horizontal support system, and three horizontal supports are set up at three depths of 0.1m, 3.9m and 7.1m. In the actual project, since one side of the foundation pit is designed to pass heavy sand trucks, the foundation pit project is considered to be in an asymmetric overload state, assuming that one side is overloaded by 30 kPa The bottom of the foundation pit excavation surface was reinforced to resist uplift, with an equivalent overload of 30 kPa The design section of the foundation pit retaining wall is as follows: Figure 3 As shown in the figure, the deformation control design of the foundation pit has been completed, but the external force received by the foundation pit retaining wall needs to be accurately described to calculate the internal force and arrange the reinforcement. First, the environmental parameters of the foundation pit retaining wall are obtained, including the characteristics of the stratum, the overload around the foundation pit, etc. The stages of earth pressure analysis for this engineering case are as follows: 1. Site environment analysis stage like Figure 2 The following is the soil layer distribution diagram of the foundation pit retaining wall. According to the cross-section diagram and survey data, the soil layer can be roughly divided into the following layers (depth is measured from the ground surface): (1) Fill layer: 0~2.8m; main components: miscellaneous fill or plain fill; bulk density γ≈18 kN / m3, internal friction angle , cohesion c≈10 kPa (Example value).

[0057] (2) Silty clay: 2.8~4.7m; bulk density γ≈18.5 kN / m3, , c≈12 kPa ; This layer has a higher water content and greater compressibility.

[0058] (3) Silty clay: 4.7~9.1m; bulk density γ≈19 kN / m3, , c≈15 kPa ; Because the silt component accounts for a significant proportion, it is more sensitive to deformation.

[0059] (4) Clay: 9.1~9.4m (or deeper); bulk density γ≈19.5 kN / m3, , c≈20 kPa ; This layer is relatively hard and provides the main embedding function.

[0060] 2. Design of retaining wall and bilateral support (1) Overview of retaining wall: Both sides adopt underground continuous wall (or pile row) form, the wall thickness is 1m, and the depth can be deepened to 18~20m according to the visual survey data to ensure sufficient embedding. The wall material is C35 concrete.

[0061] (2) Constructing horizontal support (bilateral coupling) A horizontal support (connecting beam or steel support) is set at the excavation depth of 3m, 6m, and 9m to connect the north and south retaining walls; multiple layers of support can also be set according to design requirements. The first support is reinforced concrete support. The second and third supports are steel structure supports. The specific retaining wall design parameters are as follows: Figure 4 and are input as coupled stiffness in numerical or analytical models.

[0062] (3) Clarify the key points of bilateral coupling The horizontal support "connects" the south wall and the north wall together. At the same support elevation, if one side wall displaces too much inward, the support will generate tension or pressure and transmit it to the opposite side wall, thereby "coupling" the deformation of both sides. For situations where one side is subjected to large forces (such as buildings or piles on one side and the other side is relatively empty), bilateral coupling can effectively reduce excessive displacement and bending moment of one side wall. The calculation model adopts the calculation method described in CN116383949A.

[0063] 3. Calculation parameters and non-limit earth pressure model (1) Calculation of relevant parameters required Geometry of foundation pit and retaining components: foundation pit depth 12.2m, retaining wall thickness 0.8m, burial depth 18m, etc.; Mechanical properties of soil layers: input according to the aforementioned stratified data, including bulk density, internal friction angle, cohesion, elastic modulus, permeability coefficient, etc.; Support stiffness: The stiffness of the concrete support is kc , ks 1. ks 2; Construction stage: excavation in layers, installation of supports in layers or time periods; Overload: Ground 30 kPa , regarded as a uniformly distributed load or transferred to the wall side according to a certain attenuation formula.

[0064] (2) Non-limit earth pressure model Compared with the traditional ultimate earth pressure , Kp Different from the above, the present invention adopts the earth pressure coefficient related to the wall displacement for different displacement levels of the retaining wall. K(w) ; In numerical simulation (such as PLAXIS, ABAQUS), Mohr-Coulomb, Hardening-Soil and other constitutive models can be selected to automatically update the lateral pressure following the soil deformation / stress state; This embodiment adopts theoretical analysis or simplified method to calculate the soil layer by layer.

[0065] The functional expression of the non-limit lateral pressure of the soil on one side of the active earth pressure zone is: , The functional expression of the non-limit lateral pressure of the soil on one side of the passive earth pressure zone is: , in, It indicates the additional stress in the soil caused by ground overload or dynamic load. represents the equivalent load of soil reinforcement at the bottom of the foundation pit, K(w(z) ) is between the static earth pressure coefficient and the active / passive limit by interpolation or experimental regression. The specific interpolation method is as follows. , in, is the ultimate active earth pressure coefficient, is the static earth pressure coefficient, is the ultimate passive earth pressure coefficient, is the ultimate displacement of active earth pressure, is the ultimate displacement of active earth pressure. The ultimate displacement is generally determined by local specifications. , , where H is the current side foundation pit excavation depth.

[0066] 4. Iterative calculation output results A typical construction and calculation iteration process is given below.

[0067] The final construction phase is expected to be excavated to 12.2m, at which time three supports will be installed: (1) Determine the distribution of earth pressure according to the magnitude of the ultimate earth pressure.

[0068] (2) Input the initial earth pressure distribution into the bilateral coupling deformation calculation model to calculate the deformation of the retaining wall at this stage And support .

[0069] (3) Based on the new deformation results, the updated earth pressure is calculated using the non-limit earth pressure model and .

[0070] (4) Assume that i The deformation and earth pressure calculated by the iteration are recorded as and , make a convergence judgment: Make a convergence judgment: Check , The value is chosen according to the actual accuracy required, here it is 0.5. Repeat (2) and (3) if the convergence condition is not met.

[0071] (5) Through multiple cycles of approximation, the final stable displacement curve and internal force distribution of the left and right retaining walls are obtained, as shown in Figure 3 to Figure 4 As shown, Figure 3 is the deformation curve of the foundation pit retaining wall. Figure 4 The distribution diagram of the soil pressure outside the foundation pit on the retaining piles on both sides is shown in Figure 2. Figure 5 The distribution diagram of the soil pressure inside the foundation pit on the retaining piles on both sides.

[0072] Example 3 See also Figure 6 , which is a schematic diagram of a system for calculating earth pressure of a foundation pit retaining structure under bilateral coupling deformation proposed in the third embodiment of the present application, and the system comprises: The data acquisition module 100 is used to acquire deformation associated parameters of the surrounding structure of the target foundation pit; A preliminary fitting module 200 is used to perform initial deformation fitting on the enclosure structure to obtain active and passive initial earth pressures of the enclosure structure, wherein the initial earth pressures are associated with the buried depth of the enclosure structure; The deformation prediction module 300 is used to input the deformation association parameter and the initial soil pressure into a bilateral coupling deformation calculation model to obtain the horizontal deformation of both sides of the enclosure structure; The earth pressure prediction module 400 is used to input the horizontal deformations on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the enclosure structure; The iterative convergence module 500 is used to input the soil pressure into the bilateral coupling deformation calculation model for iteration if the horizontal deformation on both sides and the soil pressure do not meet the convergence requirements.

[0073] On the other hand, the present application also proposes an electronic device, comprising: a processor; a memory for storing executable instructions of the processor; wherein the processor is configured to execute the executable instructions to implement the above-mentioned method for calculating the earth pressure of a foundation pit retaining structure under bilateral coupling deformation.

[0074] On the other hand, the present application also proposes a computer-readable storage medium. When the instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is able to execute the above-mentioned method for calculating the earth pressure of a foundation pit retaining structure under bilateral coupling deformation.

[0075] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0076] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0077] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A method for calculating earth pressure of foundation pit retaining structure under bilateral coupling deformation, characterized in that: The method comprises: Obtaining deformation correlation parameters of the retaining structure of the target foundation pit; Performing initial deformation fitting on the enclosure structure to obtain active and passive initial earth pressures of the enclosure structure, wherein the initial earth pressures are associated with the buried depth of the enclosure structure; Inputting the deformation association parameter and the initial earth pressure into a bilateral coupling deformation calculation model to obtain horizontal deformations on both sides of the retaining structure; Input the horizontal deformations on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the retaining structure; If the horizontal deformation on both sides and the soil pressure do not meet the convergence requirement, the soil pressure is input into the bilateral coupling deformation calculation model for iteration.

2. The method for calculating earth pressure of foundation pit retaining structure under bilateral coupling deformation according to claim 1 is characterized in that: The steps of performing initial deformation fitting on the retaining structure to obtain active and passive initial earth pressures of the retaining structure include: The initial deformation fitting of the enclosure structure is performed using a complete function high-order polynomial, wherein the function expression of the complete function high-order polynomial is: ， in, represents the deformation function of the preliminary fitting of the enclosure structure, z represents the buried depth of the enclosure structure, Represents the unknown coefficient parameters of the enclosure structure.

3. The method for calculating earth pressure of foundation pit retaining structure under bilateral coupling deformation according to claim 2 is characterized in that: In the step of inputting the deformation association parameter and the initial earth pressure into a bilateral coupling deformation calculation model to obtain the horizontal deformation of both sides of the enclosure structure: The deformation coordination condition is selected as the bilateral coupling deformation calculation model, wherein the function expression of the deformation coordination condition is: ， in, is the support stiffness, is the deformation of the left and right sides of the enclosure structure, To support internal strength.

4. The method for calculating earth pressure of foundation pit retaining structure under bilateral coupling deformation according to claim 2 is characterized in that: In the step of inputting the horizontal deformations on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the retaining structure: The earth pressure includes the non-limit lateral pressure of the soil on both sides of the retaining structure. The functional expression of the non-limit lateral pressure of the soil on one side of the active earth pressure zone is: ， The functional expression of the non-limit lateral pressure of the soil on one side of the passive earth pressure zone is: ， in, represents the non-limiting lateral pressure; Indicates the soil volume that changes with the buried depth or soil layer of the retaining structure; It indicates the displacement change of the enclosure structure, that is, the horizontal deformation on both sides of the enclosure structure; It represents the earth pressure coefficient that changes with the displacement of the retaining structure and varies between the active limit and the passive limit. Evolution; It indicates the additional stress in the soil caused by ground overload or dynamic load. Represents the equivalent load of soil reinforcement at the bottom of the foundation pit; Based on a simple linear assumption, exist Interpolate between: ,in, represents the static earth pressure coefficient, Represents the slope of the earth pressure fitting curve; like As it increases outward, the soil develops in the active direction. The value gradually decreases to On the contrary, the soil mass increases in the passive direction to .

5. The method for calculating earth pressure of foundation pit retaining structure under bilateral coupling deformation according to claim 4 is characterized in that: The step of inputting the horizontal deformations on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the enclosure structure also includes: If there are multiple layers of soil around the retaining structure, the soil volume and soil pressure coefficient of each layer of soil are updated, where the calculation process of the multi-layer soil pressure is: identifying the boundary and characteristic parameters of each layer of soil around the retaining structure to calculate the earth pressure of each layer of soil; The earth pressure of each soil layer is superimposed to obtain the overall multi-layer earth pressure.

6. The method for calculating earth pressure of foundation pit retaining structure under bilateral coupling deformation according to claim 1 is characterized in that: The step of inputting the deformation association parameter and the initial earth pressure into a bilateral coupling deformation calculation model to obtain the horizontal deformation of both sides of the enclosure structure also includes: If there are discrete deformation points in the distribution of horizontal deformation on both sides, the discrete deformation points are fitted to obtain a first continuous function between the buried depth of the enclosure structure and the horizontal deformation on both sides, and the first continuous function is used as the distribution function of the horizontal deformation on the left and right sides.

7. The method for calculating earth pressure of foundation pit retaining structure under bilateral coupling deformation according to claim 1 is characterized in that: The step of inputting the horizontal deformations on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the enclosure structure also includes: If there are discrete stress points in the distribution of the soil pressure, the discrete stress points are fitted to obtain a second continuous function of the buried depth of the enclosure structure and the soil pressure, and the second continuous function is used as the distribution function of the soil pressure.

8. The method for calculating earth pressure of foundation pit retaining structure under bilateral coupling deformation according to claim 1 is characterized in that: If the horizontal deformation on both sides and the soil pressure do not meet the convergence requirements, the soil pressure is input into the bilateral coupling deformation calculation model for iteration. The convergence requirements of the iteration are: ， in, and For the i The horizontal deformation and earth pressure on both sides of the retaining structure are calculated in the second iteration. and For the The horizontal deformation and earth pressure on both sides of the retaining structure are calculated in the second iteration. is the convergence accuracy.

9. A soil pressure calculation system for foundation pit retaining structure under bilateral coupling deformation, characterized in that: The system comprises: A data acquisition module is used to acquire deformation correlation parameters of the retaining structure of the target foundation pit; A preliminary fitting module is used to perform initial deformation fitting on the enclosure structure to obtain active and passive initial earth pressures of the enclosure structure, wherein the initial earth pressures are associated with the buried depth of the enclosure structure; A deformation prediction module, used for inputting the deformation association parameter and the initial earth pressure into a bilateral coupling deformation calculation model to obtain horizontal deformations on both sides of the enclosure structure; An earth pressure prediction module is used to input the horizontal deformations on both sides into a non-limit earth pressure calculation model to obtain the earth pressure of the enclosure structure; The iterative convergence module is used to input the soil pressure into the bilateral coupling deformation calculation model for iteration if the horizontal deformation on both sides and the soil pressure do not meet the convergence requirements.

10. An electronic device, characterized in that: include: processor; a memory for storing instructions executable by the processor; Wherein, the processor is configured to execute the executable instructions to implement a method for calculating earth pressure of a foundation pit retaining structure under bilateral coupling deformation as described in any one of claims 1 to 8.

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