Method and system for vertically reinforcing adjacent railway line shield working well

Abstract

The invention discloses a vertical reinforcement method and system for a shield working well adjacent to a railway line, and relates to the technical field of civil engineering construction.The vertical reinforcement method comprises the following steps that soil layer data and shield construction data of a to-be-measured area are obtained, and track settlement is predicted; acquiring micro-seismic activity data in the stratum of the to-be-measured area, and evaluating the stress state of the enclosure structure; the shield working well is reinforced according to the settlement state of the track and the stress state of the enclosure structure; according to the method, the problems that the settlement risk cannot be effectively prevented and controlled and the safety in the construction process cannot be ensured are solved by accurately predicting the settlement condition of the track and dynamically evaluating the damage risk of the shield working well.

Description

Technical Field

[0001] The present invention relates to the technical field of civil engineering construction, and more particularly to a method and system for vertically reinforcing a shield working shaft adjacent to a railway line. Background Art

[0002] Shield tunneling is a tunnel construction method that uses a shield machine to excavate the ground and simultaneously install the lining structure. It has the advantages of a high degree of automation and minimal impact on ground traffic. However, when the shield machine crosses adjacent railway lines, factors such as ground disturbance, ground loss caused by shield tunneling, and subsequent grouting pressure can cause settlement of surface and underground structures, thereby affecting the stability and safety of the railway line. Therefore, vertical reinforcement of the shield working shaft to control construction-induced ground settlement has become a key step in ensuring railway line safety.

[0003] At present, my country's underground engineering has entered a period of rapid construction. The scale and difficulty of construction are constantly increasing, and the risk factors faced during the construction process are becoming more and more complex. Especially in water-rich environments, the construction process of underground engineering foundation pits not only faces complex engineering geological conditions, but also hydrogeological conditions that bring greater risks. Therefore, people are paying more and more attention to the safety risk management of underground engineering foundation pit construction. With the expansion of the scale of cities, today's railway stations may be located in the central area of ​​the city. It is inevitable that urban planning or underground projects under construction may intersect or overlap with existing railways at different angles. The excavation of shield working shafts causes the unloading of soil and deformation of the ground surface, which affects the operational safety of adjacent railway lines. Therefore, it is very necessary and urgent to conduct in-depth research on the key technologies for vertical reinforcement of shield working shafts adjacent to railway lines.

[0004] The above disclosed technical solutions have at least the following technical problems: Traditional methods for vertically reinforcing shield tunnels adjacent to railway lines rely on empirical experience to strengthen the tunnels. However, this method fails to predict track settlement and the forces acting on the tunnel structure, effectively preventing and controlling settlement risks. This present invention addresses this issue by providing a solution. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a method and system for vertical reinforcement of a shield working shaft adjacent to a railway line. By accurately predicting the track settlement and dynamically evaluating the damage risk of the shield working shaft, the problem of being unable to effectively prevent and control the settlement risk is solved, thereby ensuring safety during the construction process.

[0006] To achieve the above object, the present invention provides the following technical solutions: A method for vertically reinforcing a shield working shaft adjacent to a railway line comprises the following steps: obtaining soil layer data and shield construction data in the area to be measured to predict track settlement; obtaining microseismic activity data within the stratum in the area to be measured to evaluate the stress state of the retaining structure; and reinforcing the shield working shaft according to the track settlement and the stress state of the retaining structure.

[0007] In a preferred embodiment, the soil layer data and shield construction data of the area to be tested are obtained to predict the track settlement, specifically as follows: exploration is arranged in the area to be tested, soil layer profiles are obtained, and soil layer data to be tested is obtained through standard penetration tests, wherein the soil layer data include soil layer strength and density; shield construction data are obtained, and the shield excavation position is matched with the corresponding soil layer data to obtain the formation loss rate, wherein the shield construction data include cutter head torque, propulsion speed, soil compartment pressure, grouting pressure and amount; a shield construction-formation response model is established based on the finite element analysis method according to the soil layer data and shield construction data; track settlement is predicted according to the construction-formation response model combined with the peck algorithm; if the track settlement prediction result exceeds the limit, the shield data is automatically adjusted.

[0008] In a preferred embodiment, the microseismic activity data inside the stratum of the test area is obtained and the stress state of the retaining structure is evaluated, specifically as follows: historical geological exploration data of the test area is obtained, the stratum structure is analyzed, and the vibration activity characteristics are extracted to construct a vibration characteristic database; the vibration signal of the test area is obtained, the vibration signal is subjected to Fourier transform method and filtering processing, and the vibration activity characteristics are extracted according to the vibration characteristic database; the microseismic source position is determined based on the artificial neural network positioning method according to the vibration activity characteristics, and the microseismic data is output, and the microseismic data includes stress release amount, focal depth, and amplitude; based on the microseismic data, the intensity of the microseismic activity is evaluated, and combined with the frequency of microseismic events, it is judged whether the retaining structure has entered the precursor stage of damage; the vibration response data of the retaining structure is obtained and combined with the intensity of the microseismic activity, the stress changes of the retaining structure affected by microseisms are simulated by finite element analysis, and combined with the acoustic emission monitoring data, the crack expansion trend is identified, the ultimate bearing capacity of the retaining structure is output, and it is judged whether reinforcement is needed.

[0009] In a preferred embodiment, the extraction of vibration activity characteristics is specifically as follows: obtaining historical data of the seismic station network in the area to be measured, and extracting the spatiotemporal distribution characteristics of historical vibration events; obtaining vibration signals based on the spatiotemporal distribution characteristics of historical vibration events, decomposing the vibration signals into energy characteristics of different frequency bands based on wavelet packet transform, and outputting the energy proportion of different frequency bands; analyzing the energy proportion of the main frequency band through the initial motion polarity of the P wave to determine the source type.

[0010] In a preferred embodiment, the shield working shaft is reinforced according to the track settlement and the stress state of the retaining structure, specifically as follows: the settlement data, microseismic energy, retaining structure stress and shield construction parameters are aligned according to timestamps to construct a multidimensional time series data set; the damage of the shield working shaft is evaluated according to the settlement data and the retaining structure stress, and a three-dimensional stratum-structure coupling model is established to simulate the structural response under different settlement amounts and stress levels to obtain settlement and damage thresholds; a two-dimensional risk matrix is ​​established according to the settlement and damage thresholds; and reinforcement is dynamically performed according to the risk level matrix.

[0011] A system for vertical reinforcement of a shield working shaft adjacent to a railway line includes a track settlement prediction module, a retaining structure stress assessment module, and a reinforcement module, with connections between the modules. The track settlement prediction module is used to obtain soil layer data and shield construction data in the area to be tested to predict track settlement; the retaining structure stress module is used to obtain microseismic activity data inside the stratum in the area to be tested to assess the stress state of the retaining structure; and the reinforcement module is used to reinforce the shield working shaft based on the track settlement and the stress state of the retaining structure.

[0012] The technical effects and advantages of the vertical reinforcement method and system of a shield working shaft adjacent to a railway line of the present invention are as follows: 1. The present invention can accurately predict track settlement by collecting soil layer data and shield construction data of the area to be tested in detail, combining finite element analysis methods and Peck algorithm. Once it is found that the settlement prediction result exceeds the safety range, the system can automatically adjust the shield construction parameters, such as cutter head torque, propulsion speed, etc., to effectively prevent and control settlement risks and ensure safety during the construction process. Utilize microseismic monitoring technology to obtain real-time microseismic activity data inside the stratum, and determine the location of the microseismic source through artificial neural network positioning method to evaluate the intensity of microseismic activity. Combined with the vibration response data of the retaining structure, finite element analysis is used to simulate the impact of microseismicity on the structure, which can timely detect the precursors of structural damage and effectively avoid the occurrence of structural damage accidents. At the same time, through acoustic emission monitoring technology, the trend of crack expansion can be further identified to provide a scientific basis for reinforcement decisions. 2. The present invention constructs a multi-dimensional time series data set by aligning the timestamps of multiple source information such as settlement data, microseismic energy, enclosure structure stress and shield construction parameters. The structural response under different settlement amounts and stress levels is simulated by a three-dimensional stratum-structure coupling model, the settlement and damage thresholds are determined, and then a two-dimensional risk matrix is ​​established. This analysis method based on big data and intelligent algorithms can realize the dynamic assessment of the damage risk of the shield working shaft, intelligently select reinforcement technology according to the risk level, and improve the efficiency and pertinence of reinforcement. According to the risk assessment results, targeted reinforcement measures are taken, such as grouting reinforcement, additional steel supports, stratum improvement, etc., to ensure the stability and safety of the shield working shaft structure. This comprehensive reinforcement strategy can not only effectively improve the structural bearing capacity, but also minimize the impact of construction on the railway line and ensure the smooth operation of railway traffic. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The present invention is a flow chart of a method for vertically reinforcing a shield working shaft adjacent to a railway line.

[0014] Figure 2 The present invention is a schematic diagram of the system structure of a method for vertically reinforcing a shield working shaft adjacent to a railway line.

[0015] Figure 3 This is a flow chart of the well construction process of the present invention.

[0016] Figure 4 This is a construction flow chart of the three-axis mixing pile of the present invention.

[0017] Figure 5 This is the plan layout of the starting well and observation well of the present invention. DETAILED DESCRIPTION

[0018] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention 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. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0019] Example 1, Figure 1 The present invention provides a method for vertically reinforcing a shield working shaft adjacent to a railway line, comprising the following steps: S1, obtain soil layer data and shield construction data of the test area to predict track settlement.

[0020] In this embodiment, soil layer data and shield construction data of the area to be measured are obtained to predict track settlement, as follows: Arrange exploration in the area to be tested, obtain soil layer profiles, and obtain soil layer data to be tested through standard penetration tests, the soil layer data including soil layer strength and density; Obtaining shield construction data, matching the shield excavation position with the corresponding soil layer data, and obtaining the formation loss rate. The shield construction data includes cutterhead torque, propulsion speed, soil chamber pressure, and grouting pressure and volume; According to the soil layer data and shield construction data, a shield construction-stratum response model was established based on the finite element analysis method; Track settlement is predicted based on the construction-stratum response model combined with the Peck algorithm; If the predicted track settlement results exceed the limit, the shield data will be automatically adjusted, including increasing the soil compartment pressure to reduce stratum loss, increasing the grouting volume or grouting pressure to fill the gap.

[0021] The calculation formula of formation loss rate is as follows:

[0022] The formula for predicting track settlement using the construction-stratum response model combined with the Peck algorithm is as follows:

[0023] Where: is the formation loss rate, is the actual excavation volume, is the theoretical excavation volume, It is the result of track subsidence. is the tunnel diameter, Is the burial depth, is the horizontal distance, is the width of the sedimentation tank.

[0024] S2, obtain microseismic activity data inside the stratum in the test area and evaluate the stress state of the retaining structure.

[0025] In this embodiment, microseismic activity data inside the stratum in the test area is obtained to evaluate the stress state of the enclosure structure, as follows: Obtain historical geological exploration data of the area to be measured, analyze the stratigraphic structure, extract vibration activity characteristics, and build a vibration characteristic database; Obtain the vibration signal of the area to be measured, perform Fourier transform on the vibration signal to remove environmental noise, and perform filtering to extract vibration activity characteristics based on the vibration feature database; The microseismic source location is determined based on the characteristics of the vibration activity using an artificial neural network positioning method, and microseismic data is output to analyze whether the microseismic event originated from shield construction or internal defects in the surrounding structure. The microseismic data includes stress release, focal depth, and amplitude. Based on microseismic data, the intensity of microseismic activity is assessed, and combined with the frequency of microseismic events, it is determined whether the retaining structure has entered the precursory stage of damage; The vibration response data of the retaining structure is obtained and combined with the intensity of microseismic activity. The stress changes of the retaining structure affected by microseismic activity are simulated through finite element analysis. Combined with acoustic emission monitoring data, the crack expansion trend is identified, the ultimate bearing capacity of the retaining structure is output, and it is determined whether reinforcement is needed.

[0026] In this embodiment, the vibration activity features are extracted as follows: Obtain historical drilling data, geological profiles, geotechnical experiment reports and earthquake history records of the area to be tested; Use geostatistical software to convert discrete drilling data into a continuous three-dimensional model to identify the distribution of faults, caves and weak interlayers; The support vector machine algorithm is used to classify stratum interfaces and divide risk areas. The 3D model is then superimposed on the shield tunneling trajectory, and the coordinates and risk levels of high-risk areas are marked in real time. Obtain historical data from the seismic network in the area to be measured and extract the spatiotemporal distribution characteristics of historical earthquake events; The vibration signal is obtained based on the spatiotemporal distribution characteristics of historical vibration events. The vibration signal is decomposed into energy characteristics of different frequency bands based on wavelet packet transform, and the energy proportion of different frequency bands is output; The source type can be determined by analyzing the energy proportion of the main frequency band through the initial polarity of the P wave; Natural earthquakes: The initial polarity of the P wave shows obvious tension / compression characteristics, and the main frequency band energy is concentrated in the low frequency band; Blasting vibration: The initial motion direction of the P wave is irregular, and the main frequency energy is concentrated in the high frequency band; Shield construction vibration: The P wave amplitude is small, the main frequency energy distribution is relatively uniform, and there are more medium and high frequency components.

[0027] The continuous three-dimensional model is as follows:

[0028] Where: Strata attribute field, is the drilling data weight, is the radial basis function, is the location of the target point, is the location of the second drilling point, is the number of holes drilled, The number of holes drilled.

[0029] S3, reinforce the shield working shaft according to the track settlement and the stress state of the surrounding structure.

[0030] In this embodiment, the shield working shaft is reinforced according to the track settlement and the stress state of the surrounding structure, as follows: Align settlement data, microseismic energy, retaining structure forces, and shield construction parameters by timestamp to construct a multidimensional time series dataset; Based on the settlement data and the stress of the surrounding structure, the shield working shaft damage was evaluated, and a three-dimensional stratum-structure coupling model was established to simulate the structural response under different settlement amounts and stress levels, and the settlement and damage thresholds were obtained. Establish a two-dimensional risk matrix based on settlement and damage thresholds; Dynamic reinforcement is performed based on the risk level matrix.

[0031] The two-dimensional risk matrix division includes: low subsidence reduces damage, low subsidence increases damage, high subsidence reduces damage, and high subsidence increases damage.

[0032] Example 2, Figure 2 The present invention provides a system for a vertical reinforcement method of a shield working shaft adjacent to a railway line, which is characterized by comprising a track settlement prediction module, a retaining structure force assessment module and a reinforcement module, and the modules are connected; Track settlement prediction module, used to obtain soil layer data and shield construction data of the test area to predict track settlement; The retaining structure stress module is used to obtain microseismic activity data inside the stratum in the test area and evaluate the stress state of the retaining structure; The reinforcement module is used to reinforce the shield working shaft according to the track settlement and the stress state of the surrounding structure.

[0033] Example 3, a shield working shaft reinforcement method, specifically as follows: The main construction management personnel and technical personnel shall carefully study and familiarize themselves with the design drawings, check the design drawings, fully understand the design intent and technical requirements, conduct a detailed investigation of the site conditions, and conduct technical explanations in advance. The laboratory shall conduct self-inspections of the steel bars, cement, sand, stone and other materials on site according to the test requirements and frequency. After the self-inspections are qualified, they shall be reported to the test supervision engineer for inspection. The concrete mix ratio shall be determined by testing and can only be used in construction after it is approved. Six observation wells are set outside the starting well and receiving well foundation pits for water level observation. The foundation pit is drained by using drainage ditches and temporary water collection wells. The survey team will survey and place the wells according to the observation well plan and on-site conditions, and mark them. If there are any ground obstacles at the well sites, they should try to remove them to facilitate drilling. When burying the mouth guard pipe, the bottom of the mouth guard pipe should be inserted into the original soil layer, and the outside of the pipe should be sealed with clay soil to prevent slurry from returning to the outside of the pipe during construction. The upper part of the mouth guard pipe should be 0.10m to 0.30m above the ground. When installing the drilling rig, in order to ensure the verticality of the hole, the machine should be installed firmly and horizontally, the big hook should be aligned with the center of the hole, the big hook, the turntable and the center of the hole should be in a straight line, the hole should be opened strictly, two drill collars should be installed at the connection between the drill bit and the drill rod, and the bent drill rod should not be lowered into the hole; The size of the mud pool is determined by the number of wells and the amount of slag discharge planned for the mud pool. Generally, every 2 to 3 wells share one mud pool, and a mud box can be used if necessary. The specific steps of well construction are as follows: The hole diameter should be uniform and the hole should be drilled to the bottom. When drilling, the large hook wire rope should be hung tightly, and light pressure and slow rotation should be used to ensure the verticality of the hole. When drilling, natural slurry should be made in the hole as much as possible. If necessary, bentonite should be added to make artificial slurry. The slurry density should be controlled at 1.10~1.15 during the drilling process. When lifting the drill tool or stopping the work, the hole must be filled with slurry to prevent the hole wall from collapsing. After the hole is drilled to the designed elevation, the drill rod is lifted to 0.50m from the bottom of the hole before the drill is lifted. Punching is performed to remove debris in the hole. At the same time, the mud density in the hole is gradually adjusted to 1.05, and the sedimentation at the bottom of the hole is less than 30cm, and the returned mud does not contain mud blocks; After the well pipe arrives at the site, the gap of the filter should be checked to see if it meets the requirements. The hole depth must be measured, and the well filter pipes must be measured and recorded one by one. The bottom of the sedimentation pipe must be sealed. To ensure that the bottom of the sedimentation pipe is firmly sealed, the lower sealing iron plate must be no less than 3mm. After the well pipe is lowered, immediately backfill the filter material according to the design requirements. The filter material should be evenly filled around the well wall, and the top surface height of the filter material layer should be measured as it is filled. After the filter material is backfilled, the well should be washed with a submersible pump within 8 hours until the well water is clear and meets the standard requirements. If filter material is found in the well water during washing, the well should be stopped, the cause should be checked, and it should be dealt with. If necessary, it should be scrapped and the well should be sealed according to the sealing requirements. The timing of sealing the well should be based on the progress of civil construction. Before sealing the well, the consent of all parties involved in the project should be obtained. The well can be sealed only after receiving the sealing order. The well can be sealed by directly backfilling the site soil. During the construction of the observation well, on-site technicians and quality inspectors control the construction quality. After the well is completed, technicians and quality inspectors will inspect the quality of the well and report it to the supervisor for acceptance if it is qualified.

[0034] The specific steps of three-axis mixing pile are as follows: Construction preparation includes site layout, road demolition, machinery installation, personnel entry and safety education, safety and quality technical briefing, cement material entry and inspection, etc. The relevant requirements shall be implemented in accordance with national and local laws, regulations, specifications and standards, design documents and the owner's requirements; Based on the provided coordinate reference points, perform layout and elevation measurement according to the design drawings, and make permanent and temporary markings. To prevent damage to control points during construction, guard piles must be placed at appropriate locations outside the construction area. After layout and positioning, prepare a surveying and technical layout form and submit it to the supervisor for review and acceptance. Mixing construction can only be carried out after confirmation. The diameter of the three-axis mixing piles is 850mm, with 3 piles forming a group (width). The axis distance of the three-axis mixer used in this project is 850mm, and the spacing between each group is 1800mm. Based on this size, red paint is used to mark the parallel groove wire or positioning steel to ensure that the mixing piles are accurately positioned every time. The construction of three-axis cement mixing piles adopts the two-spraying and two-mixing process. Cement slurry should be injected during the sinking and lifting process, and the sinking and lifting speeds should be strictly controlled. A slurry mixing platform should be built at the construction site. Two cement tanks should be placed stably near the platform. The slurry should be stirred before starting the machine, and the slurry mixing personnel should be briefed before drilling. 42.5 grade ordinary Portland cement should be used. The cement content should not be less than 20% 3.0 meters below the bottom of the foundation pit, and not less than 7% above the base. The slurry mixing and grouting volume should be converted based on the volume of reinforced soil per drilled. A slurry mixing platform was constructed at the construction site, with two cement tanks installed near the platform. The slurry should be stirred before starting the machine, and the slurry mixing personnel were briefed before drilling. 42.5-grade ordinary Portland cement was used, with the cement content not less than 20% 3.0 meters below the foundation pit bottom and not less than 7% above the foundation. The slurry mixing and grouting volume was calculated based on the volume of reinforced soil per drilled. The grouting pressure was 1.0 MPa to 2.0 MPa, controlled by the slurry delivery capacity. After soil reinforcement, the unconfined compressive strength of the mixed soil after 28 days should be ≥1 MPa.

[0035] The specific steps of earth excavation are as follows: Before the formal excavation of the foundation pit, remove the topsoil to 10cm below the bottom of the first reinforced concrete support. Use a 220 excavator to load the soil directly into the dump truck. Place the first reinforced concrete support in the same location using formwork. Once the support reaches the designed strength, excavate the second layer of soil. During excavation, be sure to protect the finished concrete and avoid collisions with the completed concrete supports. A Hitachi 120 mini excavator was positioned within the foundation pit, while a Kobe 350 long-arm excavator was positioned on the ground beside the foundation pit to excavate the second layer of earth between two adjacent reinforced concrete supports. During the excavation of the second layer, the pit was sloped at a 1:3 vertical slope and a 1:2 horizontal slope. Once excavation reached 50cm below the bottom of the second steel support, the second steel support was immediately erected. The Kobe 350 long-arm excavator then loaded the lower excavated earth onto a truck, which was then transported to a designated waste dump by a waste truck. After the second steel support was erected and prestressed, the third layer of earthwork was excavated. During the excavation of the third layer of earthwork, the longitudinal slope of the pit was 1:3 and the transverse slope was 1:2. When the excavation reached 50cm below the bottom of the third steel support, the third steel support was immediately erected. During the excavation, a Hitachi 120 excavator transferred the earthwork in the foundation pit to the excavation area of ​​the Kobe 350 long-arm excavator, and the earthwork was loaded into a dump truck. The dump truck was then transported to the designated dump storage area. After the third steel support is installed and prestressing is completed, the fourth layer of earthwork is excavated. The excavation method of the fourth layer of earthwork is basically the same as that of the third layer of earthwork. Excavation is stopped when it reaches 10 cm below the bottom of the fourth concrete support. After the cushion layer is poured, the second layer of concrete support and ring beam are started. During excavation, a Hitachi 120 excavator was used to excavate and level the top surface of the soil in the area where concrete support was required. The earthwork was loaded onto trucks and transported by a Kobe 350 long-arm excavator. In the fourth-layer excavation area, there are connectors for the ring beam that need to be excavated. When excavating the ground-connected wall area, manual labor and the excavator will be used to clean up the fallen concrete residue and the earth on the wall. It is necessary to "clean up as you dig" to ensure the connection quality of the ring beam concrete and the surrounding structure. The excavation method for the fifth and sixth layers is basically the same as that for the third and fourth layers. Due to the limited arm length of the long-arm excavator, a tire-type grab crane is used to lift and load the earth. After the fourth concrete support reaches the design strength, the fifth layer of earthwork is excavated. When the excavation reaches 50cm below the fifth steel support, the fifth steel support is immediately erected. After the fifth steel support is installed and prestressed, the sixth layer of earthwork is excavated. When the excavation reaches 50cm below the sixth steel support, the sixth steel support is immediately erected. When excavating the seventh layer of earthwork, a Hitachi 120 excavator was equipped and manual labor was used to transfer the remaining earthwork to the working area of ​​the tire grab crane, and then transport the earthwork to the dump truck.

[0036] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0037] The above embodiments may be implemented in whole or in part through software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments may be implemented in whole or in part in the form of a computer program product.

[0038] Those skilled in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0039] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0040] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

[0041] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for vertical reinforcement of a shield working shaft adjacent to a railway line, characterized in that: The steps include: Obtain soil layer data and shield construction data of the test area to predict track settlement; Obtain microseismic activity data within the strata in the test area and evaluate the stress state of the retaining structure; The shield working shaft is reinforced according to the track settlement and the stress state of the surrounding structure.

2. The vertical reinforcement method for a shield working shaft adjacent to a railway line according to claim 1 is characterized in that: The soil layer data and shield construction data of the area to be measured are obtained to predict the track settlement, specifically as follows: Arrange exploration in the area to be tested, obtain soil layer profiles, and obtain soil layer data to be tested through standard penetration tests, the soil layer data including soil layer strength and density; Obtain shield construction data, match the shield excavation position with the corresponding soil layer data, and obtain the stratum loss rate; According to the soil layer data and shield construction data, a shield construction-stratum response model was established based on the finite element analysis method; Track settlement is predicted based on the construction-stratum response model combined with the Peck algorithm; If the track settlement prediction result exceeds the limit, the shield data will be automatically adjusted.

3. The vertical reinforcement method for a shield working shaft adjacent to a railway line according to claim 2 is characterized in that: The microseismic activity data of the stratum inside the test area is obtained to evaluate the stress state of the enclosure structure, specifically as follows: Obtain historical geological exploration data of the area to be measured, analyze the stratigraphic structure, extract vibration activity characteristics, and build a vibration characteristic database; Obtain the vibration signal of the area to be measured, perform Fourier transform on the vibration signal, perform filtering, and extract the vibration activity characteristics based on the vibration feature database; Determine the microseismic source location based on the characteristics of the vibration activity using an artificial neural network positioning method, and output microseismic data, including stress release, focal depth, and amplitude; Based on microseismic data, the intensity of microseismic activity is assessed, and combined with the frequency of microseismic events, it is determined whether the retaining structure has entered the precursory stage of damage; The vibration response data of the retaining structure is obtained and combined with the intensity of microseismic activity. The stress changes of the retaining structure affected by microseismic activity are simulated through finite element analysis. Combined with acoustic emission monitoring data, the crack expansion trend is identified, the ultimate bearing capacity of the retaining structure is output, and it is determined whether reinforcement is needed.

4. The method for vertical reinforcement of a shield working shaft adjacent to a railway line according to claim 3, characterized in that: The extraction of vibration activity features is specifically as follows: Obtain historical data from the seismic network in the area to be measured and extract the spatiotemporal distribution characteristics of historical earthquake events; The vibration signal is obtained based on the spatiotemporal distribution characteristics of historical vibration events. The vibration signal is decomposed into energy characteristics of different frequency bands based on wavelet packet transform, and the energy proportion of different frequency bands is output; The energy proportion of the main frequency band is analyzed by the initial P-wave polarity to determine the earthquake source type.

5. The vertical reinforcement method for a shield working shaft adjacent to a railway line according to claim 4 is characterized in that: The shield working shaft is reinforced according to the track settlement and the stress state of the surrounding structure, as follows: Align settlement data, microseismic energy, retaining structure forces, and shield construction parameters by timestamp to construct a multidimensional time series dataset; Based on the settlement data and the stress of the surrounding structure, the shield working shaft damage was evaluated, and a three-dimensional stratum-structure coupling model was established to simulate the structural response under different settlement amounts and stress levels, and the settlement and damage thresholds were obtained. Establish a two-dimensional risk matrix based on settlement and damage thresholds; Dynamic reinforcement is performed based on the risk level matrix.

6. The method for vertical reinforcement of a shield working shaft adjacent to a railway line according to claim 5, characterized in that: The calculation formula of the formation loss rate is as follows: The formula for predicting track settlement using the construction-stratum response model combined with the Peck algorithm is as follows: Where: is the formation loss rate, is the actual excavation volume, is the theoretical excavation volume, It is the result of track subsidence. is the tunnel diameter, Is the burial depth, is the horizontal distance, is the width of the sedimentation tank.

7. A system using the method for vertical reinforcement of a shield working shaft adjacent to a railway line according to any one of claims 1 to 6, characterized in that: It includes track settlement prediction module, enclosure structure stress assessment module and reinforcement module, and there are connections between the modules; Track settlement prediction module, used to obtain soil layer data and shield construction data of the test area to predict track settlement; The retaining structure stress module is used to obtain microseismic activity data inside the stratum in the test area and evaluate the stress state of the retaining structure; The reinforcement module is used to reinforce the shield working shaft according to the track settlement and the stress state of the surrounding structure.

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