Subway expansion construction method based on staged control of horizontal deformation

Abstract

The present invention relates to the technical field of subway expansion construction, and particularly relates to a subway expansion construction method based on staged control of horizontal deformation, including delimiting a number of construction cycles based on the construction plan, carrying out foundation pit earth excavation within the construction cycles, and synchronously constructing supports. After the end of any construction cycle, obtain the feedback parameters of the construction cycle, respectively analyze the correlation between the construction speed and the horizontal deformation data and the axial force servo data to determine the influence weight of the construction speed, compare the simulation parameters and the corresponding feedback parameters, and select to carry out the construction of the next cycle, or, execute: determine the constraint conditions based on the weight of the construction speed and the feedback data, use the finite element model to regenerate the construction plan of the next construction cycle with the constraint conditions and carry out the construction of the next cycle; through the dynamic change of the construction plan with the construction speed and the axial force servo feedback data, coupling the differences in the excavation progress, it is possible to timely and effectively avoid the potential impact of horizontal deformation on subway expansion construction.

Description

Technical Field

[0001] The present invention relates to the technical field of subway expansion construction, and particularly relates to a subway expansion construction method based on staged control of horizontal deformation. Background Art

[0002] During the urban construction process, the construction around subway stations has a great impact on the stratum stability of subway stations, especially in soft soil areas. During the construction of underground structures such as foundation pit excavation, the unloading effect of the surrounding soil will cause certain deformation of the foundation pit, which will cause adjacent buildings and the like to generate corresponding position deformations along with the soil, thus endangering safety. Therefore, the traditional construction method for buildings around subway stations usually adopts the excavation method of segmented and block-by-block, which will cause deformation of the subway station soil body, especially horizontal deformation. If this horizontal deformation cannot be effectively controlled, it may lead to settlement and inclination of the subway station soil body, and even affect the overall stability of the subway station. Therefore, in order to reduce the impact of underground construction on surrounding buildings, especially the subway station body, and protect the overall stability and safety of underground structures, it is necessary to predict and control the deformation of underground structures. In the prior art, some methods predict and control stratum deformation by introducing numerical simulation. For example, a neural network is used with the existing geotechnical mechanical parameters of each subway as input values, and the horizontal displacement at the detection point when the horizontal distance between the excavation face and the monitoring point is at different positions is used as the output value for training. The trained model is used to analyze the horizontal displacement of other upcoming expansion construction. It mainly includes relevant data preparation, prediction results of the simulation process, and accuracy verification. It can predict the horizontal displacement of the structure at the detection point based on the existing geotechnical mechanical parameters of each subway, and provide a measurement basis for the structural safety of the subway station and preventing abnormal settlement.

[0003] However, there are deviations in the prediction and actual implementation process. Problems such as differences in construction speed and inaccurate soil data will lead to a decrease in the matching degree between the predicted construction plan and the actual construction scenario, thereby wasting prediction computing power and affecting the construction speed. Summary of the Invention

[0004] The purpose of the present invention is to provide a subway expansion construction method based on staged control of horizontal deformation to solve the problem in the prior art that there are deviations in the prediction and actual implementation process during the subway double-sided expansion construction, resulting in a decrease in the matching degree between the predicted construction plan and the actual construction scenario, thereby wasting prediction computing power and affecting the construction speed.

[0005] To this end, the present invention provides a subway expansion construction method based on staged control of horizontal deformation. The subway expansion construction method based on staged control of horizontal deformation includes:

[0006] Step S1, demarcating a number of construction cycles based on the construction plan;

[0007] Step S2, during the construction period, carry out foundation pit earth excavation and synchronously construct the supports, and all the supports are equipped with axial force servo systems;

[0008] Step S3, after the end of any construction period, obtain the feedback parameters of the construction period, and the feedback parameters include: construction speed, horizontal deformation data, soil data, and axial force servo data of the axial force servo system;

[0009] Step S4, analyze the correlation between the construction speed and the horizontal deformation data, and the correlation between the construction speed and the axial force servo data, so as to determine the influence weight of the construction speed;

[0010] Step S5, respectively compare the construction speed, horizontal deformation data, and axial force servo data in the feedback parameters with the corresponding simulation parameters. In response to each item in the feedback parameters matching the corresponding simulation parameters, or only the construction speed not matching the corresponding simulation parameter, carry out the construction of the next cycle according to the construction plan.

[0011] In response to any one of the horizontal deformation data and the axial force servo data not matching the corresponding simulation parameter, execute Step S6 and Step S7;

[0012] Step S6, substitute the feedback parameters into the finite element model and determine the constraint conditions for the finite element model:

[0013] If the soil data matches the corresponding simulation parameter and the influence weight of the construction speed is greater than or equal to the preset threshold, the constraint condition is to only change the construction speed.

[0014] If the soil data matches the corresponding simulation parameter and the influence weight of the construction speed is less than the preset threshold, or the soil data does not match the corresponding simulation parameter, the constraint condition is to change the construction speed and the excavation plot, and the unexcavated plot at the end of the next construction cycle is the same as the original construction plan;

[0015] Step S7, use the finite element model to regenerate the construction plan for the next construction cycle according to the constraint conditions and carry out the construction of the next cycle.

[0016] As an optimal technical solution of the subway expansion construction method based on staged control of horizontal deformation, in the step S3, the determination of the influence weight of the construction speed includes:

[0017] Step S31, divide the construction period into several segments, and determine the construction speed, horizontal deformation amount, and axial force change amount of each segment;

[0018] Step S32: Based on the construction speed, horizontal deformation amount, and axial force change amount of each section, determine the Pearson correlation coefficient between the construction speed and the horizontal deformation amount, and the Pearson correlation coefficient between the construction speed and the axial force change amount, respectively.

[0019] Step S33: Take the sum of the Pearson correlation coefficient between the construction speed and the horizontal deformation amount and the Pearson correlation coefficient between the construction speed and the axial force change amount as the influence weight of the construction speed.

[0020] As an optimal technical solution of the subway expansion construction method based on staged control of horizontal deformation, in the step S31, the axial force change amount is the difference between the axial force at the end of the construction period and the axial force at the beginning of the construction period.

[0021] As an optimal technical solution of the subway expansion construction method based on staged control of horizontal deformation, in the step S1, the construction plan is obtained by simulating through the finite element model, and the simulation parameters are generated by the finite element model simulation.

[0022] As an optimal technical solution of the subway expansion construction method based on staged control of horizontal deformation, in the step S1, the demarcation of the construction period satisfies that the period lengths of each construction period are the same.

[0023] As an optimal technical solution of the subway expansion construction method based on staged control of horizontal deformation, the soil data includes soil composition, density, internal friction angle, and cohesion.

[0024] As an optimal technical solution of the subway expansion construction method based on staged control of horizontal deformation, in the step S2, the specific process of construction support includes:

[0025] Construct the corresponding steel support when the foundation pit is excavated to the support position.

[0026] Among them, at least two support positions are included in the excavation process corresponding to a single construction period.

[0027] As an optimal technical solution of the subway expansion construction method based on staged control of horizontal deformation, before the step S1, it further includes:

[0028] Step SS1: Divide the soil body to be excavated for construction into several plots.

[0029] Step SS2: Determine the excavation plan with the horizontal deformation amount meeting the requirements as the construction plan through the finite element model and empirical data.

[0030] Among them, the construction plan includes: the excavation sequence of the plots and the construction speed of each plot.

[0031] The beneficial effects of the present invention are:

[0032] The present invention combines prediction with construction in stages, and combines the axial force servo feedback data of each stage. Through the dynamic changes of the excavation position with the excavation progress and the axial force servo feedback data, the difference in the excavation speed on both sides is coupled to avoid the minor horizontal deformation caused by the difference in the excavation speed in a single cycle. At the same time, through the phased adaptive scheme adjustment of the axial force servo, the limitations of the axial force servo are overcome, and the potential impact of horizontal deformation on the subway expansion construction can be effectively avoided in a timely manner.

[0033] By comparing the simulation parameters with the actual construction, the construction plan can be updated in stages to match the actual construction scenario. When the soil data matches the corresponding simulation parameters and the construction speed weight is greater than or equal to the preset threshold, it indicates that only changing the construction speed to reduce the horizontal deformation amount in the next cycle is effective. At this time, only changing the construction speed can avoid computing power consumption and reduction of construction efficiency. When the soil data matches the corresponding simulation parameters and the construction weight is less than the preset threshold, or the soil data does not match the corresponding simulation parameters, it indicates that changing the construction speed to reduce the horizontal deformation amount of the subway station in the next cycle has poor effect. At this time, the excavation plot should be modified synchronously to achieve the construction caused by the difference in simulation parameters. Through the above fine division and processing, through the phased horizontal deformation control, the horizontal deformation effect of the subway station is effectively reduced while ensuring the construction efficiency.

[0034] Furthermore, through the analysis of the construction speed weight, the present invention can reduce the device computing power while ensuring the effectiveness of the regenerated construction plan, and optimize the effect of the phased update of the construction plan.

[0035] Furthermore, the present invention significantly improves the accuracy and safety of subway expansion construction through the phased dynamic control and multi-source data fusion mechanism, and solves the problem of large deviation between the prediction model and the actual working conditions in the traditional method. Its core principle is to decompose the complex construction process into multiple controllable stages, and through real-time data feedback and dynamic model correction, form a closed-loop control system to ensure the scientificity and adaptability of the construction plan.

[0036] Furthermore, the finite element model dynamically corrected by the present invention can adapt to the change of soil parameters, and significantly improve the matching degree between the construction plan and the real-time working conditions.

[0037] Furthermore, the combination of the axial force servo system and the phased excavation of the present invention effectively inhibits the non-linear growth of horizontal deformation and ensures the structural stability of the subway station.

[0038] Furthermore, the construction speed adjustment strategy based on weight analysis of the present invention maximizes the utilization rate of equipment under the premise of controllable risk and shortens the overall construction period.

[0039] Furthermore, through precise plot-based construction planning and local model correction, the present invention avoids the computing power consumption of full model reconstruction and improves the efficiency of computing resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a flowchart of the subway expansion construction method based on staged control of horizontal deformation in an embodiment of the present invention;

[0041] Figure 2 It is a flowchart of step S3 in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments of the present invention fall within the protection scope of the present invention.

[0043] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions, and moreover, the first feature being "above", "over" and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "below" the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicating that the first feature has a lower horizontal height than the second feature.

[0044] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0045] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where like or similar reference numerals denote like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention.

[0046] During the construction around a subway station in soft soil areas, the soil unloading effect caused by foundation pit excavation will disturb the stress balance of the stratum, resulting in the accumulation of horizontal deformation of the subway station. Although the traditional segmented and block excavation method can partially control the deformation, due to the fluctuations in construction speed and the dynamic changes in soil parameters, the static assumptions of the prediction model fail.

[0047] Please refer to Figure 1 As shown, this embodiment provides a subway expansion construction method based on staged control of horizontal deformation to solve the above problems. The subway expansion construction method based on staged control of horizontal deformation includes:

[0048] Step SS1: Divide the soil to be excavated for construction into several plots.

[0049] Step SS2: Determine the excavation plan that meets the requirements of the horizontal deformation amount through a finite element model and empirical data as the construction plan.

[0050] Among them, the construction plan includes: the excavation sequence of the plots and the construction speed of each plot.

[0051] Step S1: Based on the construction plan, delimit several construction cycles. The delimitation of the construction cycles satisfies that the cycle lengths of each construction cycle are the same. The construction plan is obtained through finite element model simulation, and the simulation parameters are generated by the finite element model in Step SS2.

[0052] Step S2: Carry out foundation pit earth excavation within the construction cycle and synchronously construct the supports. All the supports are equipped with axial force servo systems.

[0053] Step S3: After the end of any construction cycle, obtain the feedback parameters of the construction cycle. The feedback parameters include: construction speed, horizontal deformation data (the horizontal deformation data is the horizontal deformation amount of the subway station), soil data (the soil data includes soil composition, density, internal friction angle, and cohesion), and axial force servo data of the axial force servo system (the axial force servo data is the axial force change amount within the construction cycle).

[0054] Step S4: Analyze the correlation between the construction speed and the horizontal deformation data, and the correlation between the construction speed and the axial force servo data to determine the influence weight of the construction speed.

[0055] Step S5: Compare the construction speed, horizontal deformation data, and axial force servo data in the feedback parameters with the corresponding simulation parameters respectively. In response to all items in the feedback parameters matching the corresponding simulation parameters, or only the construction speed not matching the corresponding simulation parameter, proceed with the construction of the next cycle according to the construction plan.

[0056] In response to any one of the horizontal deformation data and the axial force servo data not matching the corresponding simulation parameter, execute Step S6 and Step S7.

[0057] Step S6: Replace the feedback parameters and input them into the finite element model, and determine the constraint conditions for the finite element model:

[0058] If the soil data matches the corresponding simulation parameter and the influence weight of the construction speed is greater than or equal to the preset threshold, the constraint condition is to only change the construction speed.

[0059] If the soil data matches the corresponding simulation parameter and the influence weight of the construction speed is less than the preset threshold, or the soil data does not match the corresponding simulation parameter, the constraint condition is to change the construction speed and the excavation plot, and the unexcavated plot in the next construction cycle is the same as that in the original construction plan.

[0060] Step S7: Use the finite element model to regenerate the construction plan for the next construction cycle with the constraint conditions (while the original setting that makes the horizontal deformation meet the standard is still set in the finite element model under the above constraint conditions) and proceed with the construction of the next cycle. It should be understood that in this embodiment, the subway expansion refers to the expansion of the buildings around the subway.

[0061] In the above embodiment, by combining prediction and construction in stages, and combining the axial force servo feedback data in each stage, through the dynamic change of the excavation position with the excavation progress and the axial force servo feedback data, coupling the difference in the excavation speed on both sides, the micro horizontal deformation caused by the difference in the excavation speed in a single cycle is avoided. At the same time, through the stage - adaptive scheme adjustment with the axial force servo, the limitations of the axial force servo are overcome, and the potential impact of horizontal deformation on the subway expansion construction can be effectively avoided in a timely manner.

[0062] Specifically, in step S2, a layered and segmented excavation strategy with time limits is adopted. In this embodiment, the excavation depth of each plot does not exceed 2 m, and the excavation length of each segment does not exceed 10 m. A hydraulic backhoe excavator is used for earth excavation, and the flatness of the excavation surface is monitored in real time. For the installation of supports, a time sequence coordination should be formed with the excavation. When the excavation reaches the preset support position (in this embodiment, it is when excavating 1.5 m downward), the excavation is paused and steel supports are installed. For example, the first support is installed 0.5 m below the excavation surface, and the second support is installed 1.5 m below the excavation surface to ensure timely support. The construction process of the support includes presetting support corbels on the retaining structure, positioning with a total station to ensure that the deviation of the support axis from the design position is <5 mm. The end of the steel support is connected to the corbel by groove welding, and the weld grade is not lower than grade II. An initial axial force is applied to the support through a hydraulic jack, which is 80% of the design value in this embodiment to eliminate the installation gap. After the initial installation, an axial force servo system is configured. Specifically, pressure sensors (pressure sensor range 0 - 3000 kN, accuracy ±0.5% FS) are arranged at both ends of the support, and axial force data is collected every 10 seconds. When the axial force fluctuation exceeds ±5% of the design value, the oil pressure of the jack is adjusted through the PID control algorithm to make the axial force stable in the target range;

[0063] Furthermore, from the perspective of protecting the subway, to protect the operating subway, the time - space effect of deep foundation pit excavation is fully utilized for excavation near the subway. At the same time, high - pressure jet grouting and double - liquid grouting equipment are prepared as emergency equipment to timely make emergency plugging for the leakage of the water - stop curtain. And at the monitoring level, the settlement points, horizontal inclination points of the station structure in the excavated plot and the deformation observation points of the interval tunnel are observed at least once a day, and the maximum settlement of the station structure, the horizontal inclination of the track and the deformation of the adjacent interval tunnel are collected in time. Measures are taken from the monitoring perspective to observe the settlement points, horizontal inclination points of the station structure in the excavation section and the deformation observation points of the interval tunnel at least once a day, and the maximum settlement of the station structure, the horizontal inclination of the track and the deformation of the adjacent interval tunnel are collected in time.

[0064] Please refer to Figure 2 As shown, in step S3, the determination of the influence weight of the construction speed includes:

[0065] Step S31: Divide the construction period into several segments, and determine the construction speed, horizontal deformation amount and axial force change amount of each segment;

[0066] Step S32: Based on the construction speed, horizontal deformation amount and axial force change amount of each segment (the axial force change amount is the difference between the axial force at the end of the construction period and the axial force at the beginning of the construction period), determine the Pearson correlation coefficient between the construction speed and the horizontal deformation amount, and the Pearson correlation coefficient between the construction speed and the axial force change amount respectively;

[0067] Step S33: Use the sum of the Pearson correlation coefficient between the construction speed and the horizontal deformation and the Pearson correlation coefficient between the construction speed and the axial force change as the influence weight of the construction speed. Specifically, in the process of determining the influence weight of the construction speed, first divide each construction cycle into several consecutive time periods at fixed time intervals. The average construction speed within each time period is recorded in real time through the GNSS positioning system, and the horizontal deformation data and the axial force change data at the end of the corresponding time period are collected synchronously. Based on the data sets of each time period, calculate the Pearson correlation coefficient between the construction speed and the horizontal deformation and the Pearson correlation coefficient between the construction speed and the axial force change respectively to quantify the correlation degree of the construction speed on the deformation and the axial force fluctuation. Finally, directly add the two correlation coefficients to obtain the influence weight of the construction speed. It should be understood that for the expansion construction around the subway, it should be constructed on both sides simultaneously to balance the differences on both sides. If there is an error in the construction speed on one side, it will lead to the difference in the stability of the soil on both sides and then lead to a slight horizontal displacement of the subway station. However, due to the differences in the structure and soil data, the influence degree of the construction speed on the expansion construction is different. When there is a mismatch in the simulation parameters, through the analysis of the influence degree, it can be found in advance whether optimizing the construction speed in the next construction cycle can achieve the target control effect, avoiding the consumption of computing power and the decline of construction efficiency. In the above embodiment, by comparing the simulation parameters with the actual construction, the construction plan can be updated stage by stage to match the actual construction scenario. When the soil data matches the corresponding simulation parameters and the influence weight of the construction speed is greater than or equal to the preset threshold, it means that only changing the construction speed to reduce the horizontal deformation in the next cycle is effective. At this time, only changing the construction speed can avoid the consumption of computing power and the reduction of construction efficiency. When the soil data matches the corresponding simulation parameters and the influence weight of the construction speed is less than the preset threshold, or the soil data does not match the corresponding simulation parameters, it means that changing the construction speed to reduce the horizontal deformation of the subway station in the next cycle has a poor effect. At this time, the excavated plot should be modified synchronously to realize the construction caused by the difference in simulation parameters. Through the above fine division and processing, through the stage-by-stage horizontal deformation control, the horizontal deformation effect of the subway station is effectively reduced while ensuring the construction efficiency.

[0068] Specifically, in this embodiment, the value range of the Pearson correlation coefficient is [-1, 1], and the value range of the influence weight of the construction speed is [-2, 2]. In this embodiment, the construction is in a soft soil area, and the preset threshold is set to 0.7. For the hard rock bottom layer, the preset threshold is relatively low, for example, 0.5. Of course, in practice, the preset threshold can be comprehensively determined as other values by combining geological parameters based on the historical construction data of similar projects and statistically analyzing the correlation between the influence weight of the construction speed and the horizontal deformation control effect, as long as it meets the condition that the horizontal deformation cannot be controlled by optimizing the construction speed when the influence weight of the construction speed is less than the preset threshold.

[0069] In this embodiment, through the analysis of the influence weight of the construction speed, it is possible to reduce the device computing power while ensuring the effectiveness of the regenerated construction plan, optimize the staged update effect of the construction plan. Furthermore, through the staged dynamic control and multi-source data fusion mechanism, the accuracy and safety of the subway expansion construction are significantly improved, and the problem of large deviation between the prediction model and the actual working conditions in the traditional method is solved. The core principle is to decompose the complex construction process into multiple controllable stages, and through real-time data feedback and dynamic model correction, form a closed-loop control system to ensure the scientificity and adaptability of the construction plan. Moreover, the dynamically corrected finite element model can adapt to the change of soil parameters, significantly improving the matching degree between the construction plan and the real-time working conditions.

[0070] Obviously, the above embodiments of the present invention are merely examples for clearly explaining the present invention, and are not intended to limit the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A subway expansion construction method based on staged control of horizontal deformation, characterized in that: include: Step S1, defining several construction periods based on the construction plan; Step S2, excavating the foundation pit during the construction period, and constructing supports simultaneously, wherein the supports are all equipped with an axial force servo system; Step S3, after any construction cycle ends, obtaining feedback parameters of the construction cycle, the feedback parameters including: construction speed, horizontal deformation data, soil data and axial force servo data of the axial force servo system; Step S4, analyzing the correlation between the construction speed and the horizontal deformation data, and the correlation between the construction speed and the axial force servo data, to determine the influence weight of the construction speed; Step S5, respectively comparing the construction speed, horizontal deformation data and axial force servo data in the feedback parameters with the corresponding simulation parameters, and in response to the fact that all items in the feedback parameters match the corresponding simulation parameters, or that only the construction speed does not match the corresponding simulation parameters, performing the next cycle of construction according to the construction plan, In response to any one of the horizontal deformation data and the axial force servo data not matching the corresponding simulation parameter, executing step S6 and step S7; Step S6, replacing the feedback parameter input into the finite element model, and determining the constraint conditions for the finite element model: If the soil data matches the corresponding simulation parameters and the influence weight of the construction speed is greater than or equal to the preset threshold, the constraint condition is to change only the construction speed. If the soil data matches the corresponding simulation parameters and the influence weight of the construction speed is less than the preset threshold, or the soil data does not match the corresponding simulation parameters, the constraints are to change the construction speed and the excavation plot, and the unexcavated plot in the next construction cycle is the same as the original construction plan; Step S7, using the finite element model to regenerate the construction plan for the next construction period with constraint conditions and perform the construction of the next period.

2. The subway expansion construction method based on staged control of horizontal deformation according to claim 1 is characterized in that: In step S3, the determination of the influence weight of the construction speed includes: Step S31, dividing the construction period into several sections, and determining the construction speed, horizontal deformation and axial force change of each section; Step S32, based on the construction speed, horizontal deformation and axial force variation of each section, respectively determine the Pearson correlation coefficient between the construction speed and the horizontal deformation, and the Pearson correlation coefficient between the construction speed and the axial force variation; Step S33: The sum of the Pearson correlation coefficient between the construction speed and the horizontal deformation and the Pearson correlation coefficient between the construction speed and the axial force change is used as the influence weight of the construction speed.

3. The subway expansion construction method based on staged control of horizontal deformation according to claim 2 is characterized in that: In step S31, the axial force change is the difference between the axial force at the end of the construction period and the axial force at the beginning of the construction period.

4. The subway expansion construction method based on staged control of horizontal deformation according to claim 3 is characterized in that: In the step S1, the construction plan is obtained through the finite element model simulation, and the simulation parameters are generated by the finite element model simulation.

5. The subway expansion construction method based on staged control of horizontal deformation according to claim 4 is characterized in that: In step S1, the construction periods are defined so that the lengths of the construction periods are the same.

6. The subway expansion construction method based on staged control of horizontal deformation according to claim 1 is characterized in that: The soil data include soil composition, density, internal friction angle and cohesion.

7. The subway expansion construction method based on staged control of horizontal deformation according to claim 1 is characterized in that: In step S2, the specific process of construction support includes: When the foundation pit is excavated to the support position, the corresponding steel support is constructed; Among them, the excavation process corresponding to a single construction cycle includes at least two support positions.

8. The subway expansion construction method based on staged control of horizontal deformation according to claim 1 is characterized in that: Before step S1, the method further includes: Step SS1: Divide the soil to be excavated into several plots. Step SS2, determining an excavation scheme whose horizontal deformation meets the requirements as the construction scheme through a finite element model and empirical data; The construction plan includes: the excavation sequence of the plots, and the construction speed of each plot.

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