Soil pressure analysis method and system for retaining structure of subway double-sided excavation

Abstract

The present application relates to the field of data processing technology, and discloses a soil pressure analysis method and system for the retaining structure of the double-sided excavation of a subway. The method includes monitoring the soil pressure at multiple points around the deep excavation on both sides of the subway station to obtain the original soil stress data; eliminating the influence of process defects and correcting the geological conditions on the original soil stress data to obtain the corrected soil pressure distribution data and performing time-space coupling analysis to obtain the soil pressure evolution characteristics; performing feature analysis and support parameter optimization on the soil pressure evolution characteristics to obtain the soil pressure prediction results of the dynamic construction process; performing normal use and extreme working condition simulation on the soil pressure prediction results to obtain the soil pressure variation law under different excavation conditions; performing retaining structure force analysis and settlement impact assessment on the soil pressure variation law to obtain the safety assessment data of the retaining structure. The present application improves the efficiency and accuracy of the soil pressure analysis of the retaining structure of the double-sided excavation of the subway.

Description

Technical Field

[0001] The present application relates to the field of data processing technology, and in particular to an earth pressure analysis method and system for a retaining structure of a foundation pit for double-sided expansion of a subway. Background Art

[0002] With the acceleration of urbanization, the construction of underground projects such as subways is increasing. During the construction of deep foundation pits on both sides of subway stations, the construction environment has a significant impact on the distribution of soil pressure. Traditional soil pressure analysis methods mainly rely on empirical formulas and simplified models, such as Coulomb's earth pressure theory and Rankine's earth pressure theory. These methods can provide relatively reliable prediction results under simple geological conditions and are widely used in actual projects. At the same time, with the development of computer technology, numerical simulation methods such as finite element analysis have also been introduced into the field of soil pressure analysis, which has improved the analysis accuracy under complex working conditions.

[0003] However, the existing technology still has some shortcomings when dealing with soil pressure analysis. First, traditional methods are difficult to accurately reflect the impact of factors such as retaining structures, groundwater, and vibration on soil pressure distribution, resulting in a large deviation between the prediction results and the actual situation. Secondly, although the existing numerical simulation methods can take into account a variety of factors, the calculation process is complex and time-consuming, and it is difficult to meet the needs of real-time monitoring and rapid decision-making in engineering. In addition, the existing methods often ignore the spatiotemporal evolution characteristics of soil pressure distribution, and cannot accurately predict dynamic changes during construction, which increases construction risks. Summary of the invention

[0004] The present application provides an earth pressure analysis method and system for a subway double-sided excavation retaining structure, which is used to improve the efficiency and accuracy of earth pressure analysis of a subway double-sided excavation retaining structure.

[0005] In a first aspect, the present application provides an earth pressure analysis method for a double-sided extension pit retaining structure of a subway, the earth pressure analysis method for a double-sided extension pit retaining structure of a subway comprises: performing multi-point earth pressure monitoring around a deep foundation pit on both sides of a subway station to obtain original soil stress data;

[0006] Eliminating the influence of process defects and correcting geological conditions on the original soil stress data to obtain corrected soil pressure distribution data;

[0007] Performing a spatiotemporal coupling analysis on the modified earth pressure distribution data to obtain the earth pressure evolution characteristics during the foundation pit excavation process;

[0008] Performing characteristic analysis on the soil pressure evolution characteristics and optimizing support parameters to obtain soil pressure prediction results in a dynamic construction process;

[0009] The predicted results of soil pressure are simulated under normal use and extreme working conditions to obtain the variation law of soil pressure under different excavation conditions;

[0010] The stress analysis of the retaining structure and the impact of settlement are evaluated based on the variation law of soil pressure to obtain the safety assessment data of the retaining structure.

[0011] In a second aspect, the present application provides an earth pressure analysis system for a subway double-sided excavation retaining structure, the earth pressure analysis system for a subway double-sided excavation retaining structure comprising:

[0012] The monitoring module is used to monitor the soil pressure at multiple points around the deep foundation pits on both sides of the subway station to obtain the original soil stress data;

[0013] An elimination module is used to eliminate the influence of process defects and correct geological conditions on the original soil stress data to obtain corrected soil pressure distribution data;

[0014] An analysis module, used for performing a spatiotemporal coupling analysis on the modified earth pressure distribution data to obtain the earth pressure evolution characteristics during the foundation pit excavation process;

[0015] An optimization module is used to perform characteristic analysis on the soil pressure evolution characteristics and optimize support parameters to obtain soil pressure prediction results in a dynamic construction process;

[0016] A simulation module is used to simulate the normal use and extreme working conditions of the soil pressure prediction result to obtain the soil pressure change law under different excavation conditions;

[0017] The evaluation module is used to analyze the stress of the retaining structure and evaluate the impact of settlement on the soil pressure change law to obtain the safety evaluation data of the retaining structure.

[0018] In the technical solution provided by this application, by monitoring the soil pressure at multiple points around the deep foundation pits on both sides of the subway station, the original soil stress data is obtained, and the soil pressure distribution under complex geological conditions is fully and accurately grasped. The layout of this multi-point monitoring network not only improves the spatial resolution of the data, but also captures the local stress concentration phenomenon, providing a reliable data basis for subsequent analysis. The original soil stress data is corrected for the influence of process defects and geological conditions to obtain the corrected soil pressure distribution data, which effectively eliminates the interference of the retaining structure and geological conditions on the soil pressure distribution, making the analysis results closer to the actual situation, and greatly improving the accuracy and reliability of the soil pressure analysis. Furthermore, the modified soil pressure distribution data is analyzed in time and space coupling to obtain the soil pressure evolution characteristics during the foundation pit excavation process, revealing the law of soil pressure changes over time and space, and providing a scientific basis for dynamic monitoring and early warning during the construction process. Through this time and space coupling analysis, it is possible to better predict and respond to abnormal changes in soil pressure that may occur during the construction process. In addition, the characteristics of soil pressure evolution are analyzed and support parameters are optimized to obtain the soil pressure prediction results of the dynamic construction process, which not only optimizes the support design, but also realizes the refined management of the construction plan, effectively reduces the construction risk and improves the engineering efficiency. Especially under complex soft soil geological conditions, this hierarchical optimization method can take the most suitable support measures for different areas, ensuring safety and saving costs. On the other hand, the soil pressure prediction results are simulated for normal use and extreme working conditions to obtain the soil pressure change law under different excavation conditions. This innovation significantly improves the applicability and reliability of the method. By considering the influence of extreme meteorological conditions and construction vibration, this method can provide more comprehensive safety guarantees for engineering design and construction, and effectively prevent engineering problems caused by extreme conditions. Finally, the stress analysis of the retaining structure and the impact of settlement on the soil pressure change were carried out to obtain the safety assessment data of the retaining structure. The soil pressure analysis was closely combined with structural safety and environmental impact, providing a comprehensive safety assessment system. This achieved a comprehensive, accurate and dynamic analysis of the soil pressure of the retaining structure of the subway foundation pit on both sides, greatly improving the safety and controllability of the deep foundation pit construction on both sides of the subway station. This application improved the efficiency and accuracy of the soil pressure analysis of the retaining structure of the subway foundation pit on both sides. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0020] Figure 1A schematic diagram of an embodiment of a method for analyzing earth pressure of a retaining structure of a double-sided excavation for a subway in an embodiment of the present application;

[0021] Figure 2 It is a schematic diagram of an embodiment of the earth pressure analysis system for the retaining structure of the subway double-sided foundation pit in the embodiment of the present application. DETAILED DESCRIPTION

[0022] The embodiments of the present application provide a soil pressure analysis method and system for the retaining structure of the foundation pit for the double-sided expansion of the subway. The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments described here can be implemented in an order other than that illustrated or described here. In addition, the terms "including" or "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method and system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0023] For ease of understanding, the specific process of the embodiment of the present application is described below. Figure 1 In the embodiment of the present application, an embodiment of the earth pressure analysis method for the retaining structure of the subway double-sided excavation includes:

[0024] Step S101, monitoring soil pressure at multiple points around deep foundation pits on both sides of the subway station to obtain original soil stress data;

[0025] Step S102, eliminating the influence of process defects and correcting geological conditions on the original soil stress data to obtain corrected soil pressure distribution data;

[0026] Step S103, performing time-space coupling analysis on the modified earth pressure distribution data to obtain the earth pressure evolution characteristics during the foundation pit excavation process;

[0027] Step S104, performing characteristic analysis on the soil pressure evolution characteristics and optimizing the support parameters to obtain the soil pressure prediction result in the dynamic construction process;

[0028] Step S105, simulating the normal use and extreme working conditions of the earth pressure prediction results to obtain the changing rules of earth pressure under different excavation conditions;

[0029] Step S106: Perform stress analysis on the retaining structure and settlement impact assessment on the soil pressure variation law to obtain safety assessment data of the retaining structure.

[0030] It is understandable that the execution subject of the present application may be an earth pressure analysis system, or a terminal or a server, which is not limited here. The present application embodiment is described by taking a server as the execution subject as an example.

[0031] Specifically, the soil pressure analysis method for the retaining structure of the double-sided subway foundation pit first monitors the soil pressure at multiple points around the deep foundation pit on both sides of the subway station to obtain the original soil stress data. A comprehensive monitoring network is formed by arranging multiple soil pressure sensors around the foundation pit. The sensors use high-precision pressure sensing elements and can capture the stress changes of the soil in real time. The arrangement of the monitoring points takes into account the geometry of the foundation pit, geological conditions and expected stress distribution to ensure the representativeness and comprehensiveness of the data. For example, in a typical deep foundation pit project on both sides of a subway station, more than 100 monitoring points may be arranged around and at the bottom of the foundation pit to form a three-dimensional monitoring network. After obtaining the original data, the influence of process defects is eliminated and the geological conditions are corrected to obtain the corrected soil pressure distribution data. First, the location of the retaining structure is identified and marked, and then the influence coefficient of the retaining structure on the surrounding soil stress is calculated by statistical analysis methods. At the same time, the soil pressure data of different strata are corrected according to the geological survey data. This process involves complex data processing algorithms, including spatial interpolation and boundary condition constraint processing. Through these processes, abnormal data caused by defects in the installation process of the earth pressure acquisition device can be eliminated, and earth pressure distribution data that more accurately reflects the actual situation can be obtained.

[0032] Next, the modified earth pressure distribution data is subjected to a spatiotemporal coupling analysis to obtain the characteristics of earth pressure evolution during foundation pit excavation. Using time series analysis methods, such as wavelet transform, the earth pressure data is decomposed into trend terms, periodic terms, and random terms. Then, through spatial correlation analysis, high pressure areas and low pressure areas are identified, and an earth pressure propagation network is constructed. This analysis method can reveal the law of earth pressure variation over time and space, providing an important basis for the subsequent formulation of construction plans. Based on the characteristics of earth pressure evolution, characteristic analysis and support parameter optimization are performed to obtain the earth pressure prediction results of the dynamic construction process. This process first performs a preliminary classification of rock and soil through cluster analysis, and then optimizes the support parameters according to the mechanical properties of each classified area. The optimization process uses an iterative algorithm to obtain the optimal support scheme through multiple simulation calculations. It can effectively balance construction safety and economy. In order to evaluate the situation under different excavation conditions, the earth pressure prediction results are simulated for normal use and extreme working conditions. This includes calculating the seepage field distribution and additional stress, as well as analyzing the influence of vibration on earth pressure. Through superposition analysis, the variation law of earth pressure under different excavation conditions is obtained. It is of great significance to prevent emergencies that may occur during the construction process.

[0033] Finally, the stress analysis of the retaining structure and the impact of settlement are evaluated based on the variation of soil pressure to obtain the safety assessment data of the retaining structure. This includes calculating the stress distribution and safety factor of the retaining structure, as well as predicting the settlement risk of the surrounding subway structure. By comprehensively analyzing these factors, the final construction safety assessment report is formed.

[0034] For example, in a deep foundation pit project on both sides of a subway station with a depth of 30 meters, the original soil pressure data obtained through multi-point monitoring showed that the maximum soil pressure at the bottom of the foundation pit reached 600kPa. After eliminating the influence of process defects and correcting geological conditions, the corrected maximum soil pressure value dropped to 520kPa. The spatiotemporal coupling analysis revealed that with the increase of excavation depth, the soil pressure showed a nonlinear growth trend, and obvious stress concentration areas were formed at the corners of the foundation pit. Based on these analysis results, the geotechnical engineering was classified into three levels, and the support parameters were optimized for each level. After comprehensively considering various factors, the final safety assessment report pointed out that under the optimized support scheme, the minimum safety factor of the retaining structure was 1.8, and the maximum settlement prediction value of the surrounding subway structure was 15mm, both of which were within the safety range.

[0035] In the embodiment of the present application, by monitoring the earth pressure at multiple points around the deep foundation pits on both sides of the subway station, the original soil stress data is obtained, and the comprehensive and accurate grasp of the distribution of earth pressure under complex geological conditions is achieved. The layout of this multi-point monitoring network not only improves the spatial resolution of the data, but also captures the phenomenon of local stress concentration, providing a reliable data basis for subsequent analysis. The original soil stress data is corrected for process defects and geological conditions, and the corrected earth pressure distribution data is obtained, which effectively eliminates the interference of the retaining structure and geological conditions on the earth pressure distribution, making the analysis results closer to the actual situation, and greatly improving the accuracy and reliability of the earth pressure analysis in the retaining structure of the foundation pit on both sides of the subway. Furthermore, the modified earth pressure distribution data is analyzed in time and space coupling, and the evolution characteristics of the earth pressure during the excavation of the foundation pit are obtained, which reveals the law of change of earth pressure with time and space, and provides a scientific basis for dynamic monitoring and early warning during the construction process. Through this time and space coupling analysis, it is possible to better predict and respond to abnormal changes in earth pressure that may occur during the construction process. In addition, the characteristics of soil pressure evolution are analyzed and support parameters are optimized to obtain the soil pressure prediction results of the dynamic construction process, which not only optimizes the support design, but also realizes the refined management of the construction plan, effectively reduces the construction risk and improves the engineering efficiency. Especially under complex geological conditions, this hierarchical optimization method can take the most suitable support measures for different areas, which ensures safety and saves costs. On the other hand, the soil pressure prediction results are simulated for normal use and extreme working conditions to obtain the soil pressure change law under different excavation conditions. This innovation significantly improves the applicability and reliability of the method. It can provide more comprehensive safety guarantees for engineering design and construction. Finally, the stress analysis of the retaining structure and the settlement impact assessment of the soil pressure change law are carried out to obtain the safety assessment data of the retaining structure, which closely combines the soil pressure analysis with structural safety and environmental impact, provides a comprehensive safety assessment system, realizes the comprehensive, accurate and dynamic analysis of soil pressure, greatly improves the safety and controllability of the deep foundation pit construction on both sides of the subway station, and improves the efficiency and accuracy of the soil pressure analysis of the retaining structure of the foundation pit on both sides of the subway.

[0036] In a specific embodiment, the process of executing step S101 may specifically include the following steps:

[0037] (1) Earth pressure monitoring points were planned around the deep foundation pits on both sides of the subway station to obtain a multi-point monitoring network layout diagram. The monitoring points were buried in layers according to the multi-point monitoring network layout diagram to obtain a vertically distributed earth pressure sensor array.

[0038] (2) Calibrate and initialize the earth pressure sensor array to obtain the calibrated sensor parameters, and collect soil stress in real time based on the calibrated sensor parameters to obtain the original earth pressure time series data;

[0039] (3) The original earth pressure time series data is subjected to noise filtering and outlier processing to obtain preprocessed earth pressure data, and the preprocessed earth pressure data is subjected to spatiotemporal interpolation to obtain a continuously distributed soil stress field;

[0040] (4) Analyze the main stress directions according to the continuously distributed soil stress field to obtain the soil pressure principal stress distribution diagram, and draw contour lines on the soil pressure principal stress distribution diagram to obtain the soil stress contour line diagram;

[0041] (5) Identify stress concentration areas based on the soil stress contour map, obtain the division results of key monitoring areas, and perform high-frequency sampling on the key monitoring areas to obtain the original soil stress data.

[0042] Specifically, the soil pressure analysis method for the retaining structure of the double-sided excavation of the subway first plans the layout of soil pressure monitoring points around the deep excavation on both sides of the subway station. The geometric shape, geological conditions and expected stress distribution of the excavation are taken into account to ensure the representativeness and comprehensiveness of the monitoring data. The monitoring point layout adopts a combination of the grid method and the key point method to form a three-dimensional monitoring network around and at the bottom of the excavation. The grid method ensures the uniform distribution of the monitoring points, while the key point method increases the density of monitoring points in areas where stress concentration may occur, such as the corners of the excavation and near the retaining structure. Through this layout method, a multi-point monitoring network layout diagram is obtained. According to the multi-point monitoring network layout diagram, the monitoring points are buried in layers. The layered burial takes into account the geological stratification, and sensors are arranged at different depths and different geological layers to form a vertically distributed earth pressure sensor array. This layered burial method can capture the changes in earth pressure at different depths and under different geological conditions, providing more comprehensive data support for subsequent analysis.

[0043] Calibration and initialization of the buried earth pressure sensor array are key steps to ensure data accuracy. The calibration process includes static calibration and dynamic calibration. Static calibration calibrates the sensor through a known pressure source to determine the linearity and sensitivity of the sensor. Dynamic calibration simulates actual working conditions and tests the response characteristics of the sensor under dynamic pressure changes. The calibration parameters of each sensor are obtained through calibration, including the sensitivity coefficient and zero offset value. The initialization process sets the initial state of the sensor to ensure that all sensors are in the same reference state when monitoring begins. Using the calibrated sensor parameters, the soil stress is collected in real time to obtain the original earth pressure time series data. The data collection frequency is set according to the project requirements, usually once an hour under static conditions, and can be increased to once every 10 minutes during construction to capture rapidly changing pressure states.

[0044] After obtaining the original soil pressure time series data, noise filtering and outlier processing are performed. Noise filtering uses the wavelet transform method to decompose the signal into different frequency components, remove high-frequency noise, and retain valid signals. Outlier processing uses statistical methods, such as the triple standard deviation method, to identify and eliminate data points that obviously deviate from the normal range. Through these processes, the preprocessed soil pressure data is obtained. The preprocessed soil pressure data is interpolated in time and space to obtain a continuously distributed soil stress field. The space-time interpolation uses the Kriging interpolation method, which takes into account the spatial correlation between data points, and can make reasonable estimates between monitoring points to form a continuous stress distribution field.

[0045] According to the continuously distributed soil stress field, the principal stress direction analysis is performed to obtain the principal stress distribution diagram of soil pressure. The principal stress analysis uses the stress tensor conversion method to calculate the magnitude and direction of the principal stress at each point. It helps to understand the stress state and transmission path inside the soil. The principal stress distribution diagram of soil pressure is contoured to obtain the soil stress contour diagram. The contour drawing uses the triangular grid method to discretize the continuous stress field into a grid, and then interpolate the contour lines on the grid. It can intuitively display the spatial variation characteristics of stress distribution.

[0046] According to the soil stress contour map, stress concentration areas are identified and the key monitoring area division results are obtained. The identification process uses the gradient analysis method to calculate the spatial gradient of the stress field. The high gradient area is the stress concentration area. High-frequency sampling is performed on the identified key monitoring areas, and the sampling frequency can be increased to once per minute to capture the rapid changes in these areas, thereby obtaining more refined original soil stress data.

[0047] For example, in a deep foundation pit project on both sides of a 30-meter-deep subway station, 200 monitoring points were arranged according to the above method to form a three-dimensional monitoring network. Among them, a layer of monitoring points was set every 5 meters around the foundation pit, with 20 points in each layer and 40 points at the bottom. During the calibration process, a known pressure of 0-1000kPa was applied to each sensor, and the average sensitivity coefficient was 0.01mV / kPa and the average zero offset value was 2mV. In the initial monitoring for one week, the acquisition frequency was set once an hour, and a total of 33,600 raw data points were obtained. About 5% of high-frequency noise was removed by wavelet transform noise filtering. About 1% of data points were eliminated by outlier processing. After spatiotemporal interpolation, a three-dimensional stress field with a resolution of 0.5mx 0.5mx 0.5m was formed. The principal stress analysis showed that stress concentration occurred at the corners at the bottom of the foundation pit, and the maximum principal stress reached 600kPa. The contour map clearly shows the trend of stress gradually decreasing from the bottom to the top. In the four identified stress concentration areas, the sampling frequency was increased to once per minute for 24 hours, and a total of 5,760 high-precision data points were obtained.

[0048] In a specific embodiment, the process of executing step S102 may specifically include the following steps:

[0049] (1) The original soil stress data is marked with the location of the retaining structure to obtain a map of the influence area of ​​the retaining structure. The soil pressure data of the non-influenced area is extracted based on the map of the influence area of ​​the retaining structure to obtain the background soil pressure distribution.

[0050] (2) Statistical analysis is performed on the background earth pressure distribution to obtain the earth pressure benchmark value, and the influence coefficient of the retaining structure is calculated based on the earth pressure benchmark value to obtain the correction factor matrix;

[0051] (3) The original soil stress data is corrected by using the correction factor matrix to obtain the preliminary corrected earth pressure data, and the preliminary corrected earth pressure data is subjected to geological stratification identification to obtain a stratified earth pressure data set;

[0052] (4) Perform geological parameter inversion based on the layered earth pressure data set to obtain the geological condition correction coefficient, and use the geological condition correction coefficient to correct the layered earth pressure data set to obtain the geologically corrected earth pressure data;

[0053] (5) Perform spatial interpolation on the geologically corrected earth pressure data to obtain a continuously distributed corrected earth pressure field, and perform boundary condition constraint processing on the corrected earth pressure field to obtain corrected earth pressure distribution data.

[0054] Specifically, the spatial position of the retaining structure is precisely located using engineering design drawings and on-site measurement data, and digitally marked in three-dimensional space. After marking, the influence range of the retaining structure is determined through spatial analysis algorithms, such as buffer zone analysis, to obtain the retaining structure influence area map. This influence area map intuitively shows the influence range of the retaining structure on the stress distribution of the surrounding soil. Based on the retaining structure influence area map, the soil pressure data of the non-influenced area is extracted. Using spatial query technology, the monitoring point data outside the influence area are screened out, and these data are regarded as the background soil pressure distribution. The background soil pressure distribution reflects the natural soil pressure state that is not affected by the retaining structure, and is an important basis for subsequent analysis.

[0055] The background earth pressure distribution is statistically analyzed to calculate the earth pressure benchmark value. The statistical analysis includes calculating statistics such as the mean, standard deviation and quantile. The earth pressure benchmark value is usually the median or specific quantile value of the background earth pressure distribution, which represents the typical earth pressure level in the area. Based on the earth pressure benchmark value, the influence coefficient of the retaining structure is calculated. The calculation of the influence coefficient takes into account factors such as the type, size and depth of the retaining structure, and is obtained by comparing the difference in earth pressure inside and outside the influence area. These influence coefficients constitute a correction factor matrix, which is a two-dimensional or three-dimensional array corresponding to the correction coefficients at different positions in space. The original soil stress data is corrected using the correction factor matrix to obtain the preliminary corrected earth pressure data. The correction process is to multiply the original data with the correction factor at the corresponding position to eliminate the influence of the retaining structure. The preliminary corrected earth pressure data is subjected to geological stratification identification. Combined with the geological survey report and the spatial distribution characteristics of the earth pressure data, the earth pressure data is divided into different geological layers using cluster analysis or threshold segmentation. The earth pressure data of each geological layer constitutes a stratified earth pressure data set.

[0056] The geological parameter inversion is performed according to the layered earth pressure data set to obtain the geological condition correction coefficient. The geological parameter inversion is an optimization process. By adjusting the soil parameters (such as elastic modulus, Poisson's ratio, etc.), the calculated earth pressure distribution is closest to the measured data. The inverted parameters are used to calculate the geological condition correction coefficients, which reflect the difference between the actual geological conditions and the theoretical model. The layered earth pressure data set is corrected using the geological condition correction coefficients to obtain the geologically corrected earth pressure data. The correction process takes into account the spatial variability of geological conditions, making the data more consistent with the actual geological conditions. The geologically corrected earth pressure data are spatially interpolated to obtain a continuously distributed corrected earth pressure field. Spatial interpolation uses geostatistical methods such as Kriging or inverse distance weighted method to convert discrete monitoring point data into a continuous spatial distribution. Finally, the corrected earth pressure field is subjected to boundary condition constraint processing, taking into account the influence of factors such as foundation pit boundary, groundwater level and surrounding subway structure on the earth pressure distribution. The earth pressure field is fine-tuned through numerical simulation or boundary element analysis, and finally the corrected earth pressure distribution data that meets the actual engineering conditions are obtained.

[0057] For example, in a deep foundation pit project on both sides of a 30-meter-deep, 100-meter-long, and 50-meter-wide subway station, 300 soil pressure monitoring points were set up. Through the location marking of the retaining structure, the 50-meter-deep underground continuous wall was identified as the main retaining structure, and the impact range was 10 meters on both sides of the wall. The data of 180 monitoring points in the non-impacted area were extracted as the background soil pressure distribution, and the soil pressure baseline value was 400kPa after statistical analysis. The influence coefficient of the retaining structure was calculated, and the influence coefficient near the wall reached a maximum of 1.5, and gradually decreased to 1.0 with increasing distance. These influence coefficients were used to construct a correction factor matrix to correct the original data. After correction, based on the characteristics of the soft soil layer, the geological stratification identified four main strata: surface fill (0-3m), soft clay layer (3-15m), silty soft soil layer (15-25m) and fine sand layer (25-30m). The elastic moduli obtained by inversion of geological parameters are 10MPa, 10MPa, 5MPa and 30MPa respectively. Based on these parameters, the correction coefficient of geological conditions is calculated and the layered data is corrected. After spatial interpolation, a continuous earth pressure field with a resolution of 0.5mx 0.5mx 0.5m is obtained. Finally, considering the uplift effect at the bottom of the foundation pit and the additional load of a 10-story building 5 meters away from the periphery, and paying special attention to the influence of the high compressibility and low strength characteristics of the soft soil stratum on the stability of the foundation pit and the settlement of the surrounding buildings, the boundary condition constraints of the earth pressure field are processed.

[0058] In a specific embodiment, the process of executing step S103 may specifically include the following steps:

[0059] (1) The modified earth pressure distribution data is decomposed into time series to obtain the trend term, periodic term and random term of earth pressure change. The time series is reconstructed based on the trend term, periodic term and random term to obtain the time evolution pattern of earth pressure.

[0060] (2) Perform spatial correlation analysis on the time evolution pattern of earth pressure to obtain a spatial distribution characteristic map of earth pressure. Based on the spatial distribution characteristic map of earth pressure, high pressure areas and low pressure areas are identified to obtain a pressure gradient distribution map.

[0061] (3) Calculate the soil pressure transmission path based on the pressure gradient distribution diagram to obtain the stress propagation network, and perform topological analysis on the stress propagation network to obtain key nodes and propagation channels;

[0062] (4) Perform time series correlation analysis on key nodes and propagation channels to obtain the time lag characteristics between nodes. Based on the time lag characteristics, a spatiotemporal model of earth pressure propagation is constructed to obtain the dynamic response characteristics of earth pressure.

[0063] (5) Based on the dynamic response characteristics of soil pressure and the excavation progress data, a time-space coupling simulation is performed to obtain the evolution characteristics of soil pressure during the excavation process.

[0064] Specifically, the empirical mode decomposition (EMD) method is used to decompose the earth pressure time series data into trend terms, periodic terms and random terms. The trend term reflects the long-term change trend of earth pressure, the periodic term reflects the periodic change characteristics of earth pressure, and the random term represents short-term fluctuations and noise. After decomposition, the three components are used to reconstruct the time series to obtain the earth pressure time evolution pattern. The reconstruction process adopts the weighted superposition method, and different weights are assigned according to the contribution of each item to the original signal, so as to obtain a model that can accurately reflect the characteristics of earth pressure over time. The spatial correlation analysis of the earth pressure time evolution pattern is carried out, and the geographical weighted regression (GWR) method is used to consider the influence of spatial position on the change of earth pressure, and the spatial distribution characteristic map of earth pressure is obtained. It can reflect the spatial heterogeneity and local characteristics of earth pressure. According to the spatial distribution characteristic map, high pressure areas and low pressure areas are identified by setting thresholds or clustering analysis methods, and then the pressure gradient distribution map is drawn. The pressure gradient distribution map intuitively shows the spatial change trend and intensity of earth pressure.

[0065] Based on the pressure gradient distribution map, the minimum cost path algorithm is used to calculate the earth pressure transmission path and obtain the stress propagation network. This network reflects how the earth pressure is transmitted and distributed in space. The stress propagation network is topologically analyzed, and the key nodes and main propagation channels in the network are identified using centrality analysis methods such as degree centrality and betweenness centrality. These key nodes and propagation channels play a vital role in the entire earth pressure distribution system. Time series correlation analysis is performed on the key nodes and propagation channels, and the cross-correlation analysis method is used to calculate the time lag or lead relationship of the earth pressure changes between different nodes to obtain the time lag characteristics between nodes. The time lag characteristics reflect the propagation speed and direction of the earth pressure changes in space. The earth pressure propagation spatiotemporal model is constructed based on the time lag characteristics, which involves complex mathematical modeling. Specifically, a preliminary model based on partial differential equations is first established to describe the propagation law of earth pressure in time and space. Then, the time lag characteristics are introduced into the model as constraints, and the mathematical expression that can accurately describe the dynamic propagation process of earth pressure is obtained by solving the boundary value problem. This model not only takes into account the spatial distribution of soil pressure, but also includes the changing law in the time dimension, so it can fully reflect the dynamic response characteristics of soil pressure.

[0066] Constructing a spatiotemporal model of earth pressure propagation based on time-lag characteristics is a complex and critical step, and its purpose is to create a mathematical model that can accurately describe the propagation law of earth pressure in time and space dimensions. This process involves the following key aspects: First, using the time-lag characteristic data obtained previously, a preliminary mathematical model is established. This model usually takes the form of a partial differential equation, which takes into account the changes in earth pressure in space and time. For example, the wave equation or the diffusion equation can be used as a basis and modified and expanded according to the actual situation. Secondly, the time-lag characteristics are introduced into the model as constraints. This means adding parameters that represent the time difference of earth pressure changes between different locations to the model. These parameters reflect the propagation speed and direction of earth pressure changes, allowing the model to more accurately describe the actual situation. Then, this partial differential equation with time-lag characteristics is solved by numerical methods (such as finite difference method or finite element method). Finally, through the verification and optimization of the model, a spatiotemporal model that can accurately reflect the dynamic propagation characteristics of earth pressure is obtained. This model can not only describe the spatial distribution of earth pressure at a certain moment, but also predict its changing trend over time. The dynamic response characteristics of earth pressure refer to the overall performance of earth pressure changes over time and space obtained through this spatiotemporal model. This includes characteristics such as the propagation speed, direction, and intensity change of soil pressure. These characteristics provide an important basis for understanding the dynamic behavior of soil pressure in the retaining structure of the subway excavation on both sides, and can help engineers better predict and control the changes in soil pressure during construction, thereby formulating safer and more efficient construction plans.

[0067] Finally, the dynamic response characteristics of soil pressure and the progress data of foundation pit excavation are combined to perform space-time coupling simulation. In this step, the finite element method is used to discretize the foundation pit excavation process into multiple time steps. In each time step, the boundary conditions are updated according to the excavation progress, and the soil pressure distribution is calculated using the previously constructed space-time model of soil pressure propagation. Through this dynamic simulation, the evolution characteristics of soil pressure during foundation pit excavation are obtained, including key information such as soil pressure distribution at different excavation stages and the stress condition of the retaining structure.

[0068] For example, in a deep foundation pit project on both sides of a 30-meter-deep subway station, 30 consecutive days of soil pressure monitoring data were analyzed. After decomposing the data using the EMD method, it was found that the trend term showed a slow upward trend, with an average increase of 0.5 kPa per day; the periodic term showed obvious diurnal changes, with an amplitude of about 2 kPa; and the standard deviation of the random term was 1 kPa. Spatial correlation analysis showed that the soil pressure at the bottom of the foundation pit was 20% higher than that on the side wall on average. The pressure gradient distribution map showed that there was a high pressure concentration area at the corner of the foundation pit, with the maximum pressure gradient reaching 10 kPa / m. The stress propagation network analysis identified four key nodes, mainly located at the connection of the retaining structure. Time series correlation analysis found that the bottom soil pressure change was 1.5 hours ahead of the side wall on average. The spatiotemporal model of soil pressure propagation constructed based on these data predicted that when the foundation pit was excavated to a depth of 15 meters, the maximum soil pressure at the bottom would reach 450 kPa, and the maximum bending moment of the retaining structure would appear 5 meters below the excavation surface.

[0069] In a specific embodiment, the process of executing step S104 may specifically include the following steps:

[0070] (1) Cluster analysis is performed on the characteristics of earth pressure evolution to obtain the spatial partition results of earth pressure distribution. Based on the spatial partition results, the rock and soil are preliminarily classified to obtain the initial characteristic analysis plan;

[0071] (2) Matching the geotechnical mechanics parameters of the initial characteristic analysis scheme to obtain the mechanical characteristics description of each graded area, and calculating the support requirements of each graded area based on the mechanical characteristics description to obtain the initial value of the support parameter;

[0072] (3) Perform stress analysis on the retaining structure based on the initial values ​​of the support parameters to obtain a stress distribution diagram of the retaining structure. Perform a safety factor assessment on the stress distribution diagram of the retaining structure to obtain support parameter adjustment suggestions.

[0073] (4) Iteratively optimize the support parameters to obtain a set of candidate support schemes, and perform numerical simulation of earth pressure based on the candidate support schemes to obtain the predicted results of earth pressure distribution under each scheme;

[0074] (5) Based on the predicted results of soil pressure distribution, the schemes are evaluated and screened to obtain the optimal support scheme for dynamic construction. The soil pressure is predicted based on the optimal support scheme to obtain the predicted results of soil pressure during the dynamic construction process.

[0075] Specifically, the K-means clustering algorithm is used to classify the earth pressure data points into several categories according to their spatial distribution characteristics. Through iterative optimization, the spatial partitioning results of earth pressure distribution are obtained. Based on this result, combined with geological engineering experience, the rock and soil are preliminarily classified to form an initial characteristic analysis plan.

[0076] When matching the geotechnical parameters of the initial characteristic analysis scheme, the inversion analysis method is used. Taking the elastic modulus E as an example, the inversion formula is:

[0077]

[0078] In the formula, is the measured stress, is the corresponding strain, is Poisson's ratio. By solving this equation, the mechanical properties of each graded area are described, including elastic modulus, cohesion, internal friction angle and other parameters. Based on these mechanical properties, the support requirements of each graded area are calculated, and the initial values ​​of support parameters, such as anchor length and spacing, are obtained. According to the initial values ​​of support parameters, the force analysis of the retaining structure is carried out, and the numerical model is established using the finite element method. In the model, the retaining structure is usually simplified to beam units, and the soil is simulated with solid units. By solving the equilibrium equation:

[0079]

[0080] in, is the stiffness matrix, is the displacement vector, As the external force vector, the stress distribution diagram of the enclosure structure is obtained. The safety factor of the stress distribution diagram is evaluated, and the safety factor of each key point is calculated to obtain the support parameter adjustment suggestions. When iteratively optimizing the support parameters, a genetic algorithm is used. This algorithm simulates the natural selection and genetic process, and continuously optimizes the support parameters through operations such as crossover and mutation until a series of candidate support schemes that meet the safety and economic requirements are obtained. For each candidate scheme, the soil pressure numerical simulation is performed to obtain the soil pressure distribution prediction results under each scheme.

[0081] Finally, the schemes are evaluated and screened based on the predicted results of soil pressure distribution. The evaluation indicators include maximum soil pressure, internal force of the retaining structure, and project cost. Multi-objective decision-making methods, such as the analytic hierarchy process (AHP), are used to comprehensively consider various indicators to obtain the optimal support scheme for dynamic construction. Based on the optimal scheme, the final soil pressure prediction is carried out to obtain the soil pressure prediction results of the dynamic construction process.

[0082] For example, in a deep foundation pit project on both sides of a 30-meter-deep subway station, based on the geological characteristics of soft soil, the soil pressure data was divided into four categories through K-means cluster analysis. The cluster centers were 100kPa, 200kPa, 300kPa and 400kPa respectively. According to the clustering results, the soft soil was divided into Class I (relatively hard soft soil), Class II (medium soft soil), Class III (relatively soft soft soil) and Class IV (extremely soft soft soil). Through inversion analysis, the elastic modulus of each class of soft soil was 50MPa, 30MPa, 15MPa and 5MPa respectively. Based on these parameters, the support scheme was preliminarily determined: a 50-meter-deep underground continuous wall was used as the main enclosure structure, and an internal support system was used. A single support with a spacing of 6m was used in the Class I area, a double support with a spacing of 4m was used in the Class II area, and a three-support with a spacing of 3m was used in the Class III and Class IV areas. All supports were made of φ609mm and 16mm thick steel pipes. Finite element analysis shows that in the IV-level soft soil area, the maximum bending moment of the underground continuous wall reaches 2800kN·m, which is close to the design limit. Through genetic algorithm optimization, 5 candidate solutions were obtained. Among them, the optimal solution adds an additional prestressed support in the IV-level area, which reduces the maximum bending moment to 2200kN·m. At the same time, the soil pressure distribution is more uniform, and the maximum value is reduced from the original 420kPa to 380kPa. The final dynamic construction process predicts that when excavated to a depth of 25 meters, the maximum soil pressure at the bottom of the foundation pit will reach 350kPa, and the maximum horizontal displacement of the underground continuous wall will be 45mm, both of which are within the control range. In addition, in order to cope with the high compressibility and low bearing capacity of the soft soil foundation, a composite foundation treatment solution was designed at the bottom of the foundation pit, including cement deep mixing piles and high-pressure rotary jet piles, to enhance the stability of the base and control the uplift deformation.

[0083] In a specific embodiment, the process of executing step S105 may specifically include the following steps:

[0084] (1) Perform a baseline analysis on the earth pressure prediction results to obtain the earth pressure distribution benchmark under normal working conditions, and calculate the influencing factors based on the earth pressure distribution benchmark to obtain the seepage field distribution;

[0085] (2) Calculate the pore water pressure change based on the seepage field distribution to obtain the additional stress distribution, and superimpose the additional stress distribution on the soil pressure distribution benchmark to obtain the soil pressure distribution prediction result;

[0086] (3) Identify and locate the vibration source at the construction site, obtain the vibration propagation path map, and perform vibration wave propagation analysis based on the vibration propagation path map to obtain the vibration response characteristics of the formation;

[0087] (4) The dynamic stress increment caused by vibration is calculated based on the vibration response characteristics of the formation, and the stress superposition effect under the vibration condition is obtained. The soil pressure distribution benchmark is corrected by data superposition based on the stress superposition effect to obtain the predicted result of soil pressure distribution under the vibration condition;

[0088] (5) The predicted results of soil pressure distribution and those under vibration conditions are superimposed to obtain the variation law of soil pressure under different excavation conditions.

[0089] Specifically, the moving average method is used to calculate the average value within a certain time window to obtain the earth pressure distribution benchmark. The mathematical expression of the baseline analysis is:

[0090]

[0091] in, is the baseline value at time t, n is the time window size, is the soil pressure value at time i. Based on this benchmark, the influencing factor is calculated and the Richards equation is used to describe the seepage field distribution:

[0092]

[0093] In the formula, is the soil moisture content, is the permeability coefficient, is the total water head, is the vertical coordinate. By solving the equation, the seepage field distribution is obtained. According to the seepage field distribution, the pore water pressure change is calculated using the Terzaghi effective stress principle, and then the additional stress distribution is obtained. The additional stress is superimposed on the soil pressure distribution benchmark to obtain the soil pressure distribution prediction result.

[0094] Identify and locate the vibration source at the construction site, use triangulation to determine the location of the vibration source, and draw a vibration propagation path map. Based on the path map, use the wave equation to analyze the vibration wave propagation:

[0095]

[0096] in, is the displacement, c is the wave speed, t For time, is the displacement vector. By solving this equation, the vibration response characteristics of the formation are obtained. According to the vibration response characteristics of the formation, the dynamic stress increment caused by vibration is calculated. The dynamic stress increment is calculated using elastic wave theory, taking into account the damping characteristics of the formation. The calculated dynamic stress increment is corrected by superimposing the data with the soil pressure distribution benchmark to obtain the predicted results of the soil pressure distribution under vibration conditions.

[0097] Finally, the predicted results of soil pressure distribution under normal use and extreme working conditions are linearly superimposed to obtain the variation law of soil pressure under different excavation conditions. The superposition process takes into account the coupling effect of the two working conditions and uses the weight coefficient for adjustment.

[0098] For example, in a deep foundation pit project on both sides of a 30-meter-deep subway station, the average soil pressure at the bottom of the foundation pit under normal working conditions was 500kPa through baseline analysis. Baseline analysis was performed on the soil pressure prediction results to obtain the soil pressure distribution benchmark under normal working conditions. The influencing factors were calculated based on the benchmark to obtain the seepage field distribution. The pore water pressure change was calculated based on the seepage field distribution to obtain the additional stress distribution, and the additional stress distribution was superimposed on the soil pressure distribution benchmark to obtain the preliminary soil pressure distribution prediction results. When identifying and locating the vibration source at the construction site, it was found that there was a vibrating hammer 100 meters away from the construction site with a vibration frequency of 20Hz. Based on the identification results, a vibration propagation path diagram was drawn, and a vibration wave propagation analysis was performed to obtain the vibration response characteristics of the formation. By solving the wave equation, the maximum vibration acceleration at the bottom of the foundation pit was obtained to be 0.1g. Using the elastic wave theory, the maximum value of the dynamic stress increment caused by vibration was calculated to be 30kPa. The dynamic stress increment caused by vibration was calculated based on the vibration response characteristics of the formation to obtain the stress superposition effect under vibration conditions. The effect was used to correct the soil pressure distribution benchmark data, and the soil pressure distribution prediction results under vibration conditions were obtained. Finally, the preliminary soil pressure distribution prediction results and the soil pressure distribution prediction results under vibration conditions were superimposed to obtain the soil pressure change law under different excavation conditions. The results showed that after considering the vibration effect, the maximum soil pressure at the bottom of the foundation pit reached 580kPa, an increase of 16% over the normal working condition.

[0099] In a specific embodiment, the process of executing step S106 may specifically include the following steps:

[0100] (1) The time series of soil pressure variation under different excavation conditions is decomposed to obtain the key characteristic parameters of soil pressure variation. The load distribution of the retaining structure is calculated based on the key characteristic parameters to obtain the stress state distribution of the retaining structure.

[0101] (2) Calculate the structural stress of the stress state distribution to obtain the stress distribution diagram of the enclosure structure, and perform structural strength verification based on the stress distribution diagram to obtain the safety factor distribution of the enclosure structure;

[0102] (3) Identify the weak link data of the enclosure structure based on the safety factor distribution, obtain the potential risk point distribution map, and perform spatiotemporal evolution analysis on the potential risk point distribution map to obtain the failure probability prediction result of the enclosure structure;

[0103] (4) Analyze the impact of surface settlement on the soil pressure change law, obtain the settlement impact range and degree prediction map, and analyze the impact degree of surrounding subway structures based on the settlement impact range and degree prediction map to obtain the settlement risk level of the subway structure;

[0104] (5) Based on the predicted results of the failure probability of the retaining structure and the settlement risk level of the subway structure, a multi-factor comprehensive safety assessment is conducted to obtain the safety assessment data of the retaining structure.

[0105] Specifically, the empirical mode decomposition (EMD) method is used to decompose the earth pressure time series data into several intrinsic mode functions (IMFs) and a residual term. By analyzing the frequency characteristics and energy distribution of these IMFs, the key characteristic parameters of earth pressure changes, such as dominant frequency, amplitude and phase, are extracted.

[0106] Based on these key characteristic parameters, the earth pressure distribution theory is used to calculate the load distribution of the retaining structure, and the stress state distribution of the retaining structure is obtained. The finite element method is used to calculate the structural stress of the stress state distribution. The retaining structure is discretized into several units, the global stiffness matrix and load vector are established, the displacement field of the structure is solved, and then the stress field is obtained. The stress distribution diagram of the retaining structure is obtained, which intuitively shows the stress conditions of various parts of the structure. The structural strength is checked according to the stress distribution diagram, and the safety factor of each key point is calculated. The calculation of the safety factor takes into account the strength characteristics of the material and the geometric characteristics of the structure, thereby obtaining the safety factor distribution of the retaining structure.

[0107] According to the distribution of safety factors, the weak links of the retaining structure are identified. By setting a threshold, the areas with safety factors lower than a certain value are marked as potential risk points, and a distribution map of potential risk points is formed. The spatiotemporal evolution of these risk points is analyzed, and the Markov chain model is used to predict the changing trend of risk points over time and space. Through multiple Monte Carlo simulations, the failure probability prediction results of the retaining structure at different time points and different locations are obtained. When analyzing the influence of surface settlement on the law of soil pressure change, a method combining Peck's empirical formula and finite element method is used. The Peck formula provides a preliminary settlement estimate, while the finite element analysis takes into account the complex geological conditions and construction process to obtain a more accurate settlement impact range and degree prediction map. Based on this prediction map, combined with the structural characteristics and foundation conditions of the surrounding subway structures, the degree of impact of the building is analyzed. By setting the settlement threshold and the inclination rate threshold, the building is divided into different risk levels, such as low risk, medium risk and high risk.

[0108] Finally, the failure probability prediction results of the enclosure structure and the settlement risk level of the subway structure are comprehensively evaluated for multi-factor safety. The analytic hierarchy process (AHP) is used to weight the various risk factors and obtain a comprehensive safety index. Based on this index, combined with engineering experience and relevant specifications, the subway station construction safety assessment data is obtained.

[0109] For example, in a deep foundation pit project on both sides of a 30-meter-deep and 100-meter-long subway station, the EMD decomposition of the soil pressure monitoring data for 30 consecutive days was performed, and 5 IMFs and 1 residual term were obtained. The analysis shows that the dominant frequency is 0.5 times / day, corresponding to the periodic changes caused by the temperature difference between day and night; the maximum amplitude is 50kPa, which occurs at the bottom of the foundation pit. Based on these characteristic parameters, the maximum bending moment of the retaining structure is calculated to be 500kN·m, which occurs 15 meters from the ground surface. The finite element analysis results show that the maximum stress of the retaining structure is 180MPa, located near the connector. Through strength verification, the minimum safety factor is 1.5, which is lower than the design requirement of 1.8. Three potential risk points were identified, mainly distributed in the connector and the bottom of the foundation pit. The spatiotemporal evolution analysis predicts that if no measures are taken, the failure probability of the retaining structure at these risk points will reach 5% after 60 days.

[0110] The maximum deformation predicted by the subway station structure analysis is 25mm, mainly concentrated in the central area of ​​the station. Ten key nodes of the station structure were evaluated, of which two nodes were classified as high-risk, and the maximum stress concentration factor was expected to reach 1.8. The comprehensive evaluation results showed that the overall safety index of the project was 75 points (out of 100 points), which is at the "medium safety" level. Based on this evaluation, the monitoring and protection of high-risk nodes were strengthened, especially the connection between the station roof and the side walls, and the connectors of the enclosure structure were reinforced. At the same time, the station structure design was optimized and the stiffness of key parts was increased to improve the overall structural stability. In addition, it is necessary to closely monitor the changes in soil pressure during excavation and adjust the support measures in a timely manner to ensure the safety of the construction process and the long-term stability of the subway station structure.

[0111] The above describes the earth pressure analysis method based on the double-sided expansion pit retaining structure of the subway in the embodiment of the present application. Figure 2 The following describes the earth pressure analysis system for the double-sided extension pit retaining structure of the subway in the embodiment of the present application. The earth pressure analysis system for the double-sided extension pit retaining structure of the subway includes:

[0112] Monitoring module 201 is used to monitor the soil pressure at multiple points around the deep foundation pit on both sides of the subway station to obtain the original soil stress data;

[0113] Elimination module 202, used to eliminate the influence of process defects and calibrate geological conditions on the original soil stress data to obtain corrected soil pressure distribution data;

[0114] An analysis module 203 is used to perform a spatiotemporal coupling analysis on the modified earth pressure distribution data to obtain the earth pressure evolution characteristics during the foundation pit excavation process;

[0115] An optimization module 204 is used to perform characteristic analysis on the soil pressure evolution characteristics and optimize support parameters to obtain soil pressure prediction results during a dynamic construction process;

[0116] The simulation module 205 is used to simulate the normal use and extreme working conditions of the soil pressure prediction result to obtain the soil pressure change law under different excavation conditions;

[0117] The evaluation module 206 is used to perform stress analysis on the retaining structure and settlement impact evaluation on the soil pressure variation law to obtain safety evaluation data of the retaining structure.

[0118] Through the cooperation of the above components, the original soil stress data was obtained by monitoring the soil pressure at multiple points around the deep foundation pits on both sides of the subway station, and the soil pressure distribution under complex geological conditions was fully and accurately grasped. The deployment of this multi-point monitoring network not only improves the spatial resolution of the data, but also captures the local stress concentration phenomenon, providing a reliable data basis for subsequent analysis. The original soil stress data was corrected for process defects and geological conditions, and the corrected soil pressure distribution data was obtained, which effectively eliminated the interference of the retaining structure and geological conditions on the soil pressure distribution, making the analysis results closer to the actual situation, and greatly improving the accuracy and reliability of soil pressure analysis in the retaining structure of the foundation pit on both sides of the subway. Furthermore, the modified soil pressure distribution data was analyzed in time and space, and the evolution characteristics of soil pressure during the excavation of the foundation pit were obtained, revealing the law of soil pressure changes with time and space, and providing a scientific basis for dynamic monitoring and early warning during the construction process. Through this time and space coupling analysis, it is possible to better predict and respond to abnormal changes in soil pressure that may occur during the construction process. In addition, the characteristics of soil pressure evolution are analyzed and support parameters are optimized to obtain the soil pressure prediction results of the dynamic construction process, which not only optimizes the support design, but also realizes the refined management of the construction plan, effectively reduces the construction risk and improves the engineering efficiency. Especially under complex geological conditions, this hierarchical optimization method can take the most suitable support measures for different areas, which ensures safety and saves costs. On the other hand, the soil pressure prediction results are simulated for normal use and extreme working conditions to obtain the soil pressure change law under different excavation conditions. This innovation significantly improves the applicability and reliability of the method. By considering the influence of extreme meteorological conditions and construction vibration, this method can provide more comprehensive safety guarantees for engineering design and construction, and effectively prevent engineering problems caused by extreme conditions. Finally, the stress analysis of the retaining structure and the settlement impact assessment of the soil pressure change law are carried out to obtain the safety assessment data of the retaining structure, which closely combines the soil pressure analysis with structural safety and environmental impact, provides a comprehensive safety assessment system, realizes a comprehensive, accurate and dynamic analysis of soil pressure, greatly improves the safety and controllability of the deep foundation pit construction on both sides of the subway station, and improves the efficiency and accuracy of soil pressure analysis.

[0119] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. Earth pressure analysis method for retaining structure of subway double-sided foundation pit, characterized in that: The earth pressure analysis methods for the retaining structure of the subway double-sided excavation include: Conduct multi-point soil pressure monitoring around the deep foundation pit on both sides of the subway station to obtain the original soil stress data; Eliminating the influence of process defects and correcting geological conditions on the original soil stress data to obtain corrected soil pressure distribution data; Performing a spatiotemporal coupling analysis on the modified earth pressure distribution data to obtain the earth pressure evolution characteristics during the foundation pit excavation process, including: performing a time series decomposition on the modified earth pressure distribution data to obtain the trend term, period term and random term of the earth pressure change, and reconstructing the time series according to the trend term, period term and random term to obtain the earth pressure time evolution pattern; performing a spatial correlation analysis on the earth pressure time evolution pattern to obtain an earth pressure spatial distribution characteristic map, and identifying high pressure areas and low pressure areas according to the earth pressure spatial distribution characteristic map to obtain a pressure gradient distribution map; calculating the earth pressure transmission path according to the pressure gradient distribution map to obtain a stress propagation network, and performing a topological analysis on the stress propagation network to obtain key nodes and propagation channels; performing a time series correlation analysis on the key nodes and propagation channels to obtain the time lag characteristics between nodes, and constructing an earth pressure propagation spatiotemporal model according to the time lag characteristics to obtain the earth pressure dynamic response characteristics; performing a spatiotemporal coupling simulation according to the earth pressure dynamic response characteristics and the foundation pit excavation progress data to obtain the earth pressure evolution characteristics during the foundation pit excavation process; The empirical mode decomposition method is used to decompose the earth pressure time series data into trend term, period term and random term. The trend term reflects the long-term change trend of earth pressure, the period term reflects the periodic change characteristics of earth pressure, and the random term reflects short-term fluctuations and noise. The spatial correlation analysis of the time evolution pattern of earth pressure is carried out, and the geographically weighted regression method is used to consider the influence of spatial position on the change of earth pressure, and the spatial distribution characteristic map of earth pressure is obtained; Based on the pressure gradient distribution map, the minimum cost path algorithm is used to calculate the soil pressure transmission path and obtain the stress propagation network; the stress propagation network reflects the path of soil pressure transmission and distribution in space; Performing characteristic analysis on the soil pressure evolution characteristics and optimizing support parameters to obtain soil pressure prediction results in a dynamic construction process; The predicted results of soil pressure are simulated under normal use and extreme working conditions to obtain the variation law of soil pressure under different excavation conditions; The stress analysis of the retaining structure and the impact of settlement are evaluated based on the variation law of soil pressure to obtain the safety assessment data of the retaining structure.

2. The earth pressure analysis method for the retaining structure of the subway double-sided excavation according to claim 1 is characterized in that: The multi-point soil pressure monitoring is carried out around the deep foundation pit on both sides of the subway station to obtain the original soil stress data, including: The soil pressure monitoring points are arranged around the deep foundation pits on both sides of the subway station to obtain a multi-point monitoring network layout diagram, and the monitoring points are buried in layers according to the multi-point monitoring network layout diagram to obtain a vertically distributed soil pressure sensor array; Calibrate and initialize the soil pressure sensor array to obtain calibrated sensor parameters, and collect soil stress in real time according to the calibrated sensor parameters to obtain original soil pressure time series data; Performing noise filtering and outlier processing on the original earth pressure time series data to obtain preprocessed earth pressure data, and performing spatiotemporal interpolation on the preprocessed earth pressure data to obtain a continuously distributed soil stress field; Performing stress principal direction analysis according to the continuously distributed soil stress field to obtain a soil pressure principal stress distribution diagram, and performing contour drawing on the soil pressure principal stress distribution diagram to obtain a soil stress contour diagram; The stress concentration area is identified according to the soil stress contour map to obtain the key monitoring area division result, and the key monitoring area is sampled at high frequency to obtain the original soil stress data.

3. The earth pressure analysis method for the retaining structure of the subway double-sided excavation according to claim 1 is characterized in that: Eliminate the influence of process defects and correct geological conditions on the original soil stress data to obtain corrected soil pressure distribution data, including: Marking the original soil stress data with the location of the retaining structure to obtain a retaining structure influence area map, and extracting the soil pressure data of the non-influence area according to the retaining structure influence area map to obtain the background soil pressure distribution; Performing statistical analysis on the background earth pressure distribution to obtain an earth pressure reference value, and calculating the influence coefficient of the retaining structure according to the earth pressure reference value to obtain a correction factor matrix; The original soil stress data is corrected by using the correction factor matrix to obtain preliminary corrected soil pressure data, and the preliminary corrected soil pressure data is identified by geological stratification to obtain a stratified soil pressure data set; Performing geological parameter inversion according to the layered earth pressure data set to obtain a geological condition correction coefficient, and correcting the layered earth pressure data set using the geological condition correction coefficient to obtain geologically corrected earth pressure data; The geologically corrected earth pressure data is spatially interpolated to obtain a continuously distributed corrected earth pressure field, and the corrected earth pressure field is processed with boundary condition constraints to obtain the corrected earth pressure distribution data.

4. The earth pressure analysis method for the retaining structure of the subway double-sided excavation according to claim 1 is characterized in that: The soil pressure evolution characteristics are analyzed and support parameters are optimized to obtain the soil pressure prediction results of the dynamic construction process, including: Performing cluster analysis on the evolution characteristics of soil pressure to obtain spatial partition results of soil pressure distribution, and performing preliminary classification of rock and soil based on the spatial partition results to obtain an initial characteristic analysis plan; Matching the geotechnical mechanics parameters of the initial characteristic analysis scheme to obtain a mechanical property description of each graded area, and calculating the support requirements of each graded area according to the mechanical property description to obtain an initial value of the support parameter; Performing a stress analysis on the enclosure structure according to the initial values ​​of the support parameters to obtain a stress distribution diagram of the enclosure structure, and performing a safety factor evaluation on the stress distribution diagram of the enclosure structure to obtain support parameter adjustment suggestions; Iteratively optimize the support parameters to obtain a set of candidate support schemes, and perform numerical simulation of earth pressure based on the set of candidate support schemes to obtain prediction results of earth pressure distribution under each scheme; Schemes are evaluated and screened according to the soil pressure distribution prediction results to obtain an optimal support scheme for dynamic construction, and soil pressure prediction is performed based on the optimal support scheme to obtain soil pressure prediction results for the dynamic construction process.

5. The earth pressure analysis method for the retaining structure of the subway double-sided excavation according to claim 1 is characterized in that: The soil pressure prediction results are simulated under normal use and extreme working conditions to obtain the soil pressure variation law under different excavation conditions, including: Performing a baseline analysis on the soil pressure prediction results to obtain a soil pressure distribution benchmark under normal working conditions, and calculating the influencing factors based on the soil pressure distribution benchmark to obtain a seepage field distribution; Calculate the pore water pressure change according to the seepage field distribution to obtain the additional stress distribution, and superimpose the additional stress distribution on the soil pressure distribution benchmark to obtain the soil pressure distribution prediction result; Identify and locate the vibration source at the construction site to obtain a vibration propagation path map, and perform vibration wave propagation analysis based on the vibration propagation path map to obtain the vibration response characteristics of the formation; The dynamic stress increment caused by vibration is calculated according to the vibration response characteristics of the formation to obtain the stress superposition effect under the vibration working condition, and the soil pressure distribution benchmark is corrected by data superposition according to the stress superposition effect to obtain the soil pressure distribution prediction result under the vibration working condition; The predicted results of earth pressure distribution and those under vibration conditions are superimposed to obtain the changing rules of earth pressure under different excavation conditions.

6. The earth pressure analysis method for the retaining structure of the subway double-sided excavation according to claim 5 is characterized in that: The stress analysis of the retaining structure and the settlement impact assessment based on the soil pressure variation law are performed to obtain the safety assessment data of the retaining structure, including: Decomposing the variation law of soil pressure under different excavation conditions in time series to obtain key characteristic parameters of soil pressure variation, and calculating the load distribution of the retaining structure based on the key characteristic parameters to obtain the stress state distribution of the retaining structure; Performing structural stress calculation on the stress state distribution to obtain a stress distribution diagram of the enclosure structure, and performing structural strength verification based on the stress distribution diagram to obtain a safety factor distribution of the enclosure structure; Identify weak link data of the enclosure structure according to the safety factor distribution, obtain a potential risk point distribution map, and perform spatiotemporal evolution analysis on the potential risk point distribution map to obtain a failure probability prediction result of the enclosure structure; Analyze the influence of surface settlement on the soil pressure change law to obtain the settlement influence range and degree prediction map, and analyze the influence degree of surrounding subway structures based on the settlement influence range and degree prediction map to obtain the settlement risk level of the subway structure; Based on the prediction results of the failure probability of the retaining structure and the settlement risk level of the subway structure, a multi-factor comprehensive safety assessment is conducted to obtain the safety assessment data of the retaining structure.

7. An earth pressure analysis system for the retaining structure of a subway double-sided excavation, characterized in that: Used to execute the earth pressure analysis method for a subway double-sided excavation retaining structure according to any one of claims 1 to 6, the earth pressure analysis system for a subway double-sided excavation retaining structure comprises: The monitoring module is used to monitor the soil pressure at multiple points around the deep foundation pits on both sides of the subway station to obtain the original soil stress data; An elimination module is used to eliminate the influence of process defects and correct geological conditions on the original soil stress data to obtain corrected soil pressure distribution data; An analysis module is used to perform a spatiotemporal coupling analysis on the modified earth pressure distribution data to obtain the evolution characteristics of earth pressure during foundation pit excavation, including: performing a time series decomposition on the modified earth pressure distribution data to obtain trend terms, periodic terms and random terms of earth pressure changes, and reconstructing the time series according to the trend terms, periodic terms and random terms to obtain an earth pressure time evolution pattern; performing a spatial correlation analysis on the earth pressure time evolution pattern to obtain an earth pressure spatial distribution characteristic map, and identifying high pressure areas and low pressure areas according to the earth pressure spatial distribution characteristic map to obtain a pressure gradient distribution map; calculating the earth pressure transmission path according to the pressure gradient distribution map to obtain a stress propagation network, and performing a topological analysis on the stress propagation network to obtain key nodes and propagation channels; performing a time series correlation analysis on the key nodes and propagation channels to obtain time lag characteristics between nodes, and constructing an earth pressure propagation spatiotemporal model according to the time lag characteristics to obtain earth pressure dynamic response characteristics; performing a spatiotemporal coupling simulation according to the earth pressure dynamic response characteristics and foundation pit excavation progress data to obtain earth pressure evolution characteristics during foundation pit excavation; The empirical mode decomposition method is used to decompose the earth pressure time series data into trend term, period term and random term. The trend term reflects the long-term change trend of earth pressure, the period term reflects the periodic change characteristics of earth pressure, and the random term reflects short-term fluctuations and noise. The spatial correlation analysis of the time evolution pattern of earth pressure is carried out, and the geographically weighted regression method is used to consider the influence of spatial position on the change of earth pressure, and the spatial distribution characteristic map of earth pressure is obtained; Based on the pressure gradient distribution map, the minimum cost path algorithm is used to calculate the soil pressure transmission path and obtain the stress propagation network; the stress propagation network reflects the path of soil pressure transmission and distribution in space; An optimization module is used to perform characteristic analysis on the soil pressure evolution characteristics and optimize support parameters to obtain soil pressure prediction results in a dynamic construction process; A simulation module is used to simulate the normal use and extreme working conditions of the soil pressure prediction result to obtain the soil pressure change law under different excavation conditions; The evaluation module is used to analyze the stress of the retaining structure and evaluate the impact of settlement on the soil pressure change law to obtain the safety evaluation data of the retaining structure.

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