Subway extension construction method based on horizontal deformation staged control

Abstract

The invention relates to the technical field of metro extension, in particular to a metro extension construction method based on horizontal deformation staged control, which comprises the following steps: defining a plurality of construction periods based on a construction scheme, carrying out foundation pit earthwork excavation in the construction periods, synchronously constructing support, and obtaining feedback parameters of the construction periods after any construction period is ended, the correlation between the construction speed and the horizontal deformation data and the correlation between the construction speed and the axial force servo data are analyzed to determine the influence weight of the construction speed, the simulation parameters and the corresponding feedback parameters are compared, and construction of the next period is selected, or the following steps are executed: determining constraint conditions based on the weight of the construction speed and the feedback data; using the finite element model to regenerate a construction scheme of the next construction period under the constraint condition, and performing construction of the next period; through dynamic change of a construction scheme along with construction speed and axial force servo feedback data, the difference of excavation progress is coupled, and potential influence of horizontal deformation on subway extension construction can be timely and effectively avoided.

Description

Technical Field

[0001] The invention relates to the technical field of subway extension and construction, and in particular to a subway extension and 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 those in soft soil areas. During the construction of underground structures such as foundation pit excavation, the unloading effect of the surrounding soil will cause the foundation pit to deform to a certain extent, thereby causing the adjacent buildings to deform accordingly along with the soil, thus endangering safety. Therefore, the construction method of traditional buildings around subway stations usually adopts a segmented and block-by-block excavation method, which will cause deformation of the subway station soil, especially horizontal deformation. If this horizontal deformation cannot be effectively controlled, it may cause the settlement and tilt of the subway station soil, and even affect the overall stability of the subway station. Therefore, in order to reduce the impact of underground construction on surrounding buildings, especially subway stations, 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 to take the geotechnical parameters of existing subways as input values, and the horizontal displacement at the detection point is used as the output value for training at different positions of the horizontal distance between the excavation surface and the monitoring point. The trained model is used to analyze the horizontal displacement of other construction projects that are about to be expanded. It mainly includes relevant data preparation, simulation process prediction results and accuracy verification. It can predict the horizontal displacement of the structure at the detection point based on the existing geotechnical mechanics parameters of each subway, and provide a measurement basis for the structural safety of subway stations and the prevention of abnormal settlement.

[0003] However, there are deviations between the prediction and the actual implementation process, such as differences in construction speed and inaccurate soil data, which will lead to a decrease in the matching between the predicted construction plan and the actual scene construction, 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, so as to solve the problem that in the prior art, there is a deviation between the prediction and the actual implementation process in the process of subway double-sided expansion construction, which leads to a decrease in the matching between the predicted construction plan and the actual scene construction, thereby wasting prediction computing power and affecting the construction speed.

[0005] To this end, the present invention provides a subway extension construction method based on staged control of horizontal deformation, and the subway extension construction method based on staged control of horizontal deformation includes: Step S1, defining a number of 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.

[0006] As a preferred technical solution of the subway expansion construction method based on staged control of horizontal deformation, 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.

[0007] As a preferred technical solution for the subway expansion construction method based on staged control of horizontal deformation, 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.

[0008] As a preferred technical solution for the subway expansion construction method based on staged control of horizontal deformation, in 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.

[0009] As a preferred technical solution for the subway expansion construction method based on staged control of horizontal deformation, in step S1, the construction periods are defined so that the lengths of the construction periods are the same.

[0010] As a preferred technical solution for a subway expansion construction method based on staged control of horizontal deformation, the soil data includes soil composition, density, internal friction angle and cohesion.

[0011] As a preferred technical solution of the subway expansion construction method based on staged control of horizontal deformation, 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.

[0012] As a preferred technical solution of the subway expansion construction method based on staged control of horizontal deformation, before step S1, it also includes: Step SS1: Divide the soil to be excavated into several plots. Step SS2, determining an excavation scheme with a horizontal deformation amount that 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.

[0013] The beneficial effects of the present invention are: The present invention combines prediction and construction in stages, combines the axial force servo feedback data of each stage, and couples the difference in excavation speed on both sides through the dynamic change of the excavation position with the excavation progress and the axial force servo feedback data, so as to avoid the slight horizontal deformation caused by the difference in excavation speed in a single cycle. At the same time, through the staged 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 subway expansion and construction can be avoided in a timely and effective manner.

[0014] 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 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 computing power consumption and reduced 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 means that changing the construction speed to reduce the horizontal deformation of the subway station in the next cycle is not effective. At this time, the excavation plot should be modified synchronously to realize the construction caused by the difference in simulation parameters. Through the above-mentioned fine division and processing, through staged horizontal deformation control, the horizontal deformation effect of the subway station is effectively reduced while ensuring construction efficiency.

[0015] Furthermore, the present invention can reduce equipment computing power and optimize the phased updating effect of the construction plan while ensuring the effectiveness of the regenerated construction plan through analysis of the construction speed weight.

[0016] Furthermore, the present invention significantly improves the accuracy and safety of subway expansion and construction through staged 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 form a closed-loop control system through real-time data feedback and dynamic model correction to ensure the scientificity and adaptability of the construction plan.

[0017] Furthermore, the dynamically corrected finite element model of the present invention can adapt to changes in soil parameters, thereby significantly improving the matching degree between the construction plan and the real-time working conditions.

[0018] Furthermore, the combination of the axial force servo system of the present invention and staged excavation effectively suppresses the nonlinear growth of horizontal deformation and ensures the stability of the subway station structure.

[0019] Furthermore, the construction speed adjustment strategy of the present invention, based on weight analysis, maximizes the utilization rate of excavation equipment under the premise of controllable risks, thereby shortening the overall construction period.

[0020] Furthermore, the present invention avoids the consumption of computing power for full model reconstruction and improves the efficiency of computing resources through precise plot-based construction planning and local model correction. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of a subway expansion construction method based on staged control of horizontal deformation in an embodiment of the present invention; Figure 2 Flow chart of step S3 in the embodiment of the present invention. DETAILED DESCRIPTION

[0022] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are 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 therefore cannot be understood as limiting 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 the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "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 or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0026] During the construction around subway stations in soft soil areas, the soil unloading effect caused by foundation pit excavation will disturb the stress balance of the strata, resulting in the accumulation of horizontal deformation of the subway station. Although the traditional segmented and block excavation method can partially control the deformation, the static assumption of the prediction model becomes invalid due to the fluctuation of construction speed and the dynamic changes of soil parameters.

[0027] See also Figure 1As shown, this embodiment provides a subway extension construction method based on staged control of horizontal deformation to solve the above problems. The subway extension construction method based on staged control of horizontal deformation includes: Step SS1: Divide the soil to be excavated into several plots. Step SS2, determining an excavation scheme with a horizontal deformation amount that meets the requirements as a construction scheme through a finite element model and empirical data; Among them, the construction plan includes: the excavation order of the plots, and the construction speed of each plot.

[0028] Step S1, delineating a number of construction periods based on the construction plan, the delineation of the construction periods satisfies that the period lengths of the construction periods are the same, the construction plan is obtained through finite element model simulation, and the simulation parameters are generated by the finite element model simulation in step SS2; 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, feedback parameters of the construction cycle are obtained, the feedback parameters including: construction speed, horizontal deformation data (the horizontal deformation data is the horizontal deformation 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 within the construction cycle); 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, in response to the fact that all items in the feedback parameters match the corresponding simulation parameters, or only the construction speed does not match the corresponding simulation parameters, the next cycle of construction is carried out 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 parameters with inputs into the finite element model, and determining the constraints 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 with constraints (while the above constraints are in place, the finite element model still sets the original setting that makes the horizontal deformation meet the standard) to regenerate the construction plan for the next construction period and carry out the construction of the next period. It should be understood that in this embodiment, the expansion of the subway refers to the expansion of buildings around the subway.

[0029] In the above embodiment, prediction and construction are combined in stages, and the axial force servo feedback data of each stage are combined. The excavation position changes dynamically with the excavation progress and the axial force servo feedback data, and the difference in excavation speed on both sides is coupled to avoid slight horizontal deformation caused by the difference in excavation speed in a single cycle. At the same time, the limitations of the axial force servo are overcome through the staged adaptive adjustment of the axial force servo, and the potential impact of horizontal deformation on subway expansion and construction can be avoided in a timely and effective manner.

[0030] In detail, in step S2, a layered and segmented excavation strategy is adopted. In this embodiment, the excavation depth of each plot does not exceed 2m, and the length of each segment does not exceed 10m. A hydraulic backhoe is used for earth excavation, and the flatness of the excavation surface is monitored in real time. For support installation, it should be coordinated with the excavation in time. When excavation reaches the preset support position, in this embodiment, excavation is suspended every 1.5m, and steel supports are installed. For example, the first support is installed at 0.5m below the excavation surface, and the second support is installed at 1.5m below the excavation surface to ensure timely support. The construction process of the support includes: presetting the support bracket on the enclosure structure, positioning with a total station, ensuring that the deviation between the support axis and the design position is less than 5mm, and the steel support end and the bracket are connected by groove welding. The weld grade is not less than level 2, and the initial axial force is applied to the support by a hydraulic jack, which is 80% of the design value in this embodiment to eliminate the installation gap. After the initial installation, the axial force servo system is configured, specifically, pressure sensors are arranged at both ends of the support (pressure sensor range 0-3000kN, accuracy ±0.5%FS), and axial force data is collected every 10 seconds. When the axial force fluctuation exceeds ±5% of the design value, the jack oil pressure is adjusted by the PID control algorithm to stabilize the axial force in the target range; Furthermore, from the perspective of protecting the subway, in order to protect the operating subway, the time and space effects of deep foundation pit excavation are fully utilized for excavation near the subway. At the same time, high-pressure rotary jetting and double-liquid grouting equipment are prepared as emergency equipment to timely block the leakage of the water-stop curtain. At the monitoring level, the settlement points, horizontal inclination points and deformation observation points of the station structure of the excavated area 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 section tunnels are collected in time. Measures are taken from the monitoring perspective to observe the settlement points, horizontal inclination points and deformation observation points of the station structure of the excavated section 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 section tunnels are collected in time.

[0031] See also Figure 2 As shown, 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 (the axial force variation 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) 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 taken as the influence weight of the construction speed. In detail, in the implementation process of determining the influence weight of the construction speed, each construction cycle is first divided into several continuous time periods at fixed time intervals, and the average construction speed in each time period is recorded in real time by the GNSS positioning system, and the horizontal deformation data and the axial force change data at the end of the corresponding time period are synchronously collected. Based on the data sets of each time period, the Pearson correlation coefficients of the construction speed and the horizontal deformation and the Pearson correlation coefficients of the construction speed and the axial force change are calculated respectively to quantify the correlation degree of the construction speed with the deformation and axial force fluctuations. Finally, the two correlation coefficients are directly added to obtain the influence weight of the construction speed. It should be understood that for the expansion and construction around the subway, it should be constructed on both sides simultaneously in order to balance the differences on both sides. If there is an error in the construction speed on one side, it will lead to differences in soil stability on both sides and then cause a slight horizontal displacement of the subway station. However, due to the differences in structural and soil data, the degree of influence of construction speed on the expansion and construction is different. When there is a mismatch in simulation parameters, the analysis of the degree of influence can find out in advance whether optimizing the construction speed in the next construction cycle can achieve the target control effect, thereby avoiding computing power consumption and reduced construction efficiency. In the above embodiment, by comparing the simulation parameters with the actual construction, the construction plan can be updated in stages to match the actual construction scene. 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 of the next cycle is effective. At this time, only changing the construction speed can avoid computing power consumption and reduced 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 is not effective. At this time, the excavation plot should be modified synchronously to realize the construction caused by the difference in simulation parameters. Through the above-mentioned fine division and processing, through staged horizontal deformation control, the horizontal deformation effect of the subway station is effectively reduced while ensuring construction efficiency.

[0032] 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. The preset threshold set for the hard rock bottom is relatively low, and is 0.5 for example. Of course, in implementation, the preset threshold can be combined with geological parameters based on historical construction data of similar projects, and the correlation between the influence weight of the construction speed and the horizontal deformation control effect is statistically analyzed, and other values ​​are comprehensively determined to meet the requirement that when the influence weight of the construction speed is less than the preset threshold, the horizontal deformation cannot be controlled by optimizing the construction speed.

[0033] In this implementation, by analyzing the weight of the impact of construction speed, it is possible to reduce the computing power of the equipment while ensuring the effectiveness of the regenerated construction plan, optimize the phased update effect of the construction plan, and then, through the phased dynamic control and multi-source data fusion mechanism, significantly improve the accuracy and safety of subway expansion construction, and solve 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 form a closed-loop control system through real-time data feedback and dynamic model correction to ensure the scientificity and adaptability of the construction plan. In addition, the dynamically corrected finite element model can adapt to the changes in soil parameters, which significantly improves the matching degree between the construction plan and the real-time working conditions.

[0034] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should 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 with a horizontal deformation amount that 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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