CN111058855A - Deformation control method and evaluation system for shield underpassing structure - Google Patents

Abstract

The invention relates to a deformation control method and an evaluation system for a shield underpassing structure. The method comprises the following steps: establishing a numerical analysis model of shield tunneling, outputting a primary safety assessment and a first construction parameter which can be used for evaluating the safety of a structure based on a numerical analysis result; the method comprises the steps that monitoring points used for collecting parameters capable of representing deformation of the structure are arranged on a construction site based on a numerical analysis result, a monitoring center is established, the monitoring center outputs actual safety assessment capable of being used for evaluating safety of the structure according to monitoring data fed back by the monitoring points, and under the condition that at least one safety parameter in the actual safety assessment is within a danger threshold value, the first construction parameter is adjusted by combining the preliminary safety assessment and the actual safety assessment, so that the structure is in a controllable and/or safe state in the shield penetration construction process.

Description

Deformation control method and evaluation system for shield underpassing structure

Technical Field

The invention relates to the technical field of tunnel engineering, in particular to a deformation control method and an evaluation system for a structure penetrating under a shield.

Background

As an important component of urban underground space, urban subways have gained large-scale development in China. Except for underground railways, various urban highway tunnels, railway tunnels, municipal tunnels, civil air defense tunnels, power cable tunnels and other underground tunnels are built in succession in each large city to solve the problem of increasingly serious urban space congestion. However, in the process of building tunnels in cities, due to geological conditions and construction process limitations, the excavation and throwing of the shield tunneling machine inevitably disturbs the surrounding environment, thereby endangering the safe and normal use of adjacent structures (such as earth surface structures, pile foundations, underground pipelines, foundation pits and adjacent built pipelines). The problem of damage to structures around tunnels is becoming more and more pronounced.

The Beijing subway is one of the signs of urban traffic in China, has been developed for nearly 55 years since the construction of the subway in 1965, has large development scale and high development speed, and achieves revolutionary breakthrough in the construction technical level. The Beijing subway No. 12 line is a three-loop line and is an encryption line in the Beijing north, wherein the three-way bridge station is positioned at the high-speed east side of an airport. The design trend of the west dam river station-three-way bridge station is as follows: the three-ring bridge is laid along the north east road and the south east road, the left line increases the line spacing to 35m by a group of R-1200m reverse curves, the three-ring bridge bypasses from two sides of the three-ring west bridge to pass through, the front left line of the airport expressway adjusts the line trend by an R-400m curve and the right line by an R-400m curve and reduces the line spacing to 17.2m, and the three-ring bridge is turned to the east side of the airport expressway for the first time to be laid after passing through the ramp bridge of the three-ring bridge downwards and reaches the west dam river station. The safety benefits of shield construction of Beijing as the national political culture center and the main cities for developing and constructing subways are particularly sensitive and prominent, so that the reinforcing of the shield construction risk management and control and the safety control technology research of the Beijing subways has very important significance and is very urgent.

The method comprises the steps that at present, shield construction management basically establishes shield construction hazard source identification, shield construction system risk evaluation and shield risk system scientific control; a centralized and vertical risk management system and a comprehensive risk management system covering all shield project risks are established from the owner to the construction unit from bottom to top, and an enterprise internal control and operation mechanism for effectively balancing the risks and the return management capacity is established; from the technical aspect, the information collection, processing and control of the whole shield construction process can be basically realized by depending on the conventional shield risk control platform. However, for a single line and a certain mark section, only basic information can be read from the information platform, and for various types of crossing risk source regions, only plane position relations exist, and supplement of space relations and time relations is lacked. The function of the platform mainly depends on the transmission of the existing monitoring data, particularly taking settlement monitoring as an example, a large amount of monitoring personnel are needed, the pre-judgment and early warning on the crossing process cannot be realized, and the information storage of the construction crossing process is delayed

In the shield construction process, the original stress of the soil body is redistributed due to soil body loss, surrounding pore water pressure change, lining deformation and the like, and the original soil body balance state is damaged, so that the ground surface is subjected to sinking deformation, inclined deformation, curvature deformation, horizontal movement deformation, discontinuous deformation and the like. When the ground surface is moved and deformed greatly, safety problems such as cracking, settlement and inclination of adjacent structures on the ground or underground are caused. For example,

firstly, the influence of shield construction on a ground structure is mainly shown as follows:

(1) the structure can be wholly sunk due to the ground surface settlement;

(2) uneven settlement will cause the earth surface to incline, so that the structure is easy to generate structural damage to form cracks;

(3) the deformation of the soil body can lead the surface of the earth to form a curved surface to generate curvature, the curvature of the surface of the earth can cause the middle part of the structure to be greatly settled and the end part to be slightly settled, the middle part of the structure is suspended, and the end part is sheared;

(4) the structure is sensitive to the surface tensile deformation, when the side face of the foundation is subjected to outward horizontal thrust, the weak part is easy to crack, and meanwhile, the door and window hole is deformed, the roof is bulged, and the longitudinal wall or the enclosing wall is folded.

Second, the influence of shield construction on underground pipelines

(1) Causing transverse and longitudinal bending of the pipe, with the degree of transverse bending being much greater than longitudinal bending.

(2) The pipe is easily twisted and even cracked.

(3) Excessive tension and compression can cause the pipe joint to leak or even break away.

(4) The large axial shear or bending moment can cause the pipe to crack laterally.

Therefore, the problem of preventing the damage of the structure due to the construction of the tunnel is the core content of the research of many experts and engineers in the field.

For example, chinese patent publication No. CN102996136B discloses a method for controlling deformation of a shield short-distance downward-penetrating composite foundation structure. It includes: determining construction characteristics of the underpassing structure, wherein the construction characteristics comprise structure protection registration and foundation form, and pre-protection facilities mainly based on reinforcement are carried out on the existing structure foundation and foundation of the structure according to the construction characteristics; carrying out three-dimensional finite element simulation analysis on each construction sequence and method during the downward penetration of the shield, finding out a structural object weak area of a structural object and determining a preliminary shield propulsion scheme; carrying out construction monitoring on the structure, including vertical settlement monitoring and crack observation of the building, peripheral surface settlement profile monitoring, and adjusting a primary shield propulsion scheme to obtain an improved scheme; using an improved propulsion scheme to carry out propulsion construction during the period that the shield penetrates the structure; and performing secondary grouting after the shield is penetrated downwards and constructing a supporting structure, wherein the supporting structure construction is to construct the supporting structure from the corresponding duct piece below the structure to the soil body outside the duct piece after the shield penetrates through the upper structure.

For example, chinese patent publication No. CN102733816B discloses a method for controlling deformation when a shield passes through a structure at a short distance. Firstly, analyzing the influence of shield tunneling on a stratum and a structure under different supporting pressure ratios and different grouting effects by adopting a numerical analysis method, and providing the optimal supporting stress ratio and the requirements on the grout performance; secondly, reinforcing the stable control of the shield excavation surface, improving the slag in the pressure chamber into a flow-plastic state in a slag improvement mode, reducing the fluctuation of pressure control, and controlling the over excavation by comparing the actual slag quality and the theoretical slag quality of the measured slag; finally, the performance control of the grouting liquid after the wall is reinforced, and the grouting liquid with high density and thixotropy is adopted, so that the grouting liquid can not run off and even fill the gap of the shield tail. In the shield tunneling process, safety monitoring is also enhanced, and the safety of an adjacent building is ensured even if shield tunneling parameters are adjusted.

For example, chinese patent publication No. CN103334763B discloses a method for controlling the influence of a shield penetrating through a hard rock layer on an adjacent pile foundation. The method comprises the following steps: step one, establishing a shield tunneling finite element numerical analysis model, analyzing the influence of shield thrust and torque on an adjacent pile foundation in a hard stratum, and evaluating the influence degree; vertically slotting the side, close to the shield tunneling side, of the pile foundation, wherein the slotting depth is 2-3 m from the top of the pile foundation to the lower side of the tunnel tunneled by the shield tunneling, placing an inclinometer pipe in the slot and extending out of the ground, filling soft materials in the slot, and covering the top of the slot for protection; and step three, performing low-speed shield tunneling, monitoring horizontal displacement of the pile foundation by using a side inclined pipe, and performing feedback adjustment on shield tunneling parameters according to monitoring data.

For example, chinese patent publication No. CN102312673B discloses a construction method for a shield to pass through an operated subway tunnel at a short distance under a complex working condition. The method comprises the following specific steps: 1. analyzing a mathematical model of the crossing working condition; 2. setting construction parameters; 3. establishing implementation monitoring during shield crossing and monitoring of a tunnel and a surrounding environment; 4. shield construction: controlling construction parameters, synchronously grouting and double-liquid grouting. The method provided by the patent can enable the shield to successfully pass through the operated subway tunnel, and ensure the operation safety of the subway train.

For example, chinese patent publication No. CN107092802A discloses a shield propulsion surface deformation risk analysis method based on HAZOP-deviation. It includes: determining a standard value and a range of a risk factor in shield tunnel construction; acquiring an actual monitoring value of the risk factor parameter, analyzing the shield tunnel construction condition, and acquiring the deviation, the basic accuracy, the total accuracy and the consequence analysis of the risk factor parameter; the risk analysis method for the shield construction surface deformation based on the HAZOP-deviation degree is simple to operate and plays a guiding role in risk prevention of the surface deformation in the shield propulsion stage.

For example, chinese patent publication No. CN102900441B discloses a chinese tunnel construction method based on complete deformation control of surrounding rocks. The method comprises the following implementation steps: (1) and (3) geological determination: tunnel engineering geological exploration and comprehensive evaluation of the physical and mechanical characteristics of surrounding rocks are carried out, and classification and physical and mechanical parameters of the tunnel surrounding rocks are determined; (2) standard establishment: predicting the deformation of the tunnel surrounding rock, and formulating a surrounding rock deformation control standard and a preliminary design scheme meeting the safety and the economical efficiency; (3) and (3) planning a strategy: specific deformation control strategies are made according to the whole deformation process, and a surrounding rock deformation control target is decomposed into each construction process in the construction drawing design; (4) the process comprises the following steps: monitoring measurement and information feedback are carried out in the whole construction process, key construction positions and key construction procedures are monitored, the safety of the project is judged, and a response is made in time; (5) and (3) state evaluation: and evaluating the state of the supporting structure in time, evaluating the long-term stability of the tunnel surrounding rock structure, and performing reasonable reinforcement at each position if necessary.

In the prior art, the arrangement of monitoring points mainly determines the length of an observation line according to shield scale, hydrogeological conditions and the like, and the monitoring points are arranged along a tunnel axis (longitudinal section) and a vertical tunnel axis (transverse section). For example, the length between monitoring points arranged along the tunneling direction of tunnel excavation is generally not greater than the length of a shield machine, and the distance between two measuring points is generally 3-5 m. The distance between the monitoring cross sections is generally 20-30 m, the measuring points are arranged on the monitoring cross sections from two sides of the central line of the section in an increasing mode according to the distance between the measuring points (2-5 m), and the arrangement range is 2-3 times of the outer diameter of the shield. However, under different engineering conditions, the types and risks of damage of structures are different, and the most dangerous parts cannot be monitored by arranging monitoring points according to experience, so that the existing technical means has the following defects in structure risk identification: poor monitoring of weak points of the structure or damage to the structure already present but not monitored (e.g. corner cracks).

Furthermore, on the one hand, due to the differences in understanding to the person skilled in the art; on the other hand, since the inventor has studied a lot of documents and patents when making the present invention, but the space is not limited to the details and contents listed in the above, however, the present invention is by no means free of the features of the prior art, but the present invention has been provided with all the features of the prior art, and the applicant reserves the right to increase the related prior art in the background.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a deformation control method of a shield underpassing structure, which comprises the following steps:

and establishing a numerical analysis model of shield tunneling, and outputting a preliminary safety assessment and construction parameters which can be used for evaluating the safety of the structure based on the numerical analysis result. The numerical analysis result can display the stress, strain and displacement conditions of the structure (and the adjacent soil body) in the shield tunneling process, the danger points of the structure can be known from the stress cloud picture, the strain cloud picture and the displacement cloud picture, and the initial safety assessment for evaluating the structure in the shield tunneling process can be output based on the stress cloud picture, the strain cloud picture and the displacement cloud picture. Secondly, after the physical model of the numerical analysis is established, the safety influence of different construction parameters and different stratum parameters on the structure in the shield penetration process can be analyzed only by adjusting the boundary conditions (such as the construction parameters and the stratum parameters such as the cutter head rotating speed, the propelling speed, the grouting pressure and the like), and the sensitive factors influencing the safety state of the structure can be determined for a specific engineering object by combining the orthogonal experiment principle. Therefore, construction parameters can be preliminarily drawn up according to the numerical analysis result, and particularly, sensitive factors can be identified in an early stage.

And arranging monitoring points for acquiring parameters capable of representing the deformation of the structure on a construction site based on the numerical analysis result, and establishing a monitoring center. In the invention, the arrangement basis of the monitoring points is from the numerical analysis result, and the arrangement of the monitoring points is not obtained based on empirical judgment because the numerical analysis is established according to the actual working condition. In this way, the invention also has the following advantages: 1. the monitoring points can acquire mechanical parameters of the most easily damaged part of the structure based on the dangerous points of the structure reflected by the stress cloud picture, the strain cloud picture and the displacement cloud picture, and are favorable for monitoring weak links in the shield downward penetration process; 2. the monitoring points can adopt different types of data acquisition devices based on different types of dangerous points of the structure reflected by the stress cloud picture, the strain cloud picture and the displacement cloud picture, for example, strain sensors can be adopted for the monitoring points aiming at parts with larger stress or parts with larger stress concentration, and displacement sensors can be adopted for the monitoring points aiming at the parts with larger displacement, so that the actually acquired data can effectively monitor the types of the parts which are easy to damage according to the numerical analysis result; 3. the monitoring data fed back by the monitoring points can be processed by a monitoring center and then output to be used for evaluating the actual safety assessment of the safety of the structure, the actual safety assessment can be mutually supplemented and mutually verified with the primary safety assessment, and the monitoring data processing method is mainly used for optimizing or adjusting construction parameters according to monitoring results and numerical simulation results so that the structure is in a controllable and/or safe state in the shield penetration construction process.

According to a preferred embodiment, the numerical analysis result can be at least used for determining the type of the arranged monitoring points and/or the relative position relationship of the monitoring points, wherein the type of the monitoring points at least comprises displacement monitoring points for monitoring the displacement of the structure, and the arrangement position of the displacement monitoring points is determined at least based on the displacement cloud chart and/or the strain cloud chart in the numerical analysis result; and/or the monitoring intervals of the monitoring points adjacent to each other are arranged in a manner of negative correlation with the displacement values in the displacement cloud picture and/or the strain values in the strain cloud picture.

According to a preferred embodiment, in the case where the change with time of the feedback data of the monitoring point is greater than or equal to a deformation rate threshold value set based on the result of the numerical analysis, the monitoring frequency of the monitoring point is set based on the change with time of the feedback data; or under the condition that the change of the feedback data of the monitoring point along with the time is smaller than a threshold value set on the basis of a numerical analysis result, the monitoring frequency of the monitoring point is set on the basis of the numerical analysis result.

According to a preferred embodiment, in the case that the distance between the shield machine and the structure is smaller than a distance threshold value set on the basis of the numerical analysis result, the monitoring frequency of the monitoring point is increased; and/or the arrangement number of the monitoring points is increased and the monitoring distance between the adjacent monitoring points is reduced.

According to a preferred embodiment, different underpass sections are combined, the risk underpass sections are identified based on the numerical analysis result and the settlement control quantity, and when the shield underpass to the risk underpass sections, the monitoring mode of the monitoring points constructs a topology monitoring network according to the following mode: increasing the monitoring frequency of the monitoring point; and/or increasing the arrangement number of the monitoring points; and/or increasing the arrangement density of the monitoring points; and/or changing the arrangement mode of the monitoring points.

According to a preferred embodiment, the deformation rate threshold value can be set at least as follows: acquiring a sinking curve of a structure in the process of simulating the shield tunneling process based on a numerical analysis result, and dividing the sinking curve into an early-stage sinking curve, a middle-stage sinking curve and a later-stage sinking curve according to the advancing path of a shield cutter head and the rule of the sinking curve, wherein an early-stage deformation rate threshold value is set based on the early-stage sinking curve; setting a medium-term deformation rate threshold value based on the medium-term sinking curve; setting a later deformation rate threshold value based on the later sinking curve; wherein, the curve of sinking corresponds in earlier stage the shield structure blade disc does not pass through the stage of structure, the curve of sinking corresponds in middle stage has the shield structure blade disc is passing through the stage of structure, the curve of sinking corresponds in later stage the shield structure blade disc has passed through the stage of structure.

According to a preferred embodiment, the influence of the physical properties of the formation surrounding the tunnel to be built on the deformation of the structure is preliminarily analyzed according to the numerical analysis model, and a mechanical configuration scheme and/or a support reinforcement scheme are preliminarily formulated in combination with the control of the settlement amount, wherein the physical properties of the formation refer to a constitutive model of the formation, which at least comprises an internal friction angle, a poisson's ratio and/or an elastic modulus.

According to a preferred embodiment, the construction parameters comprise at least earth pressure, shield thrust, single-disc torque and/or tunneling speed; the numerical analysis model can be used for analyzing the correlation between the soil bin pressure, the shield thrust, the single disc torque and/or the tunneling speed and the structural deformation, so that the control method can select sensitive factors influencing the structural deformation from the soil bin pressure, the shield thrust, the single disc torque and/or the tunneling speed based on the numerical analysis result.

According to a preferred embodiment, a system for evaluating deformation of a structure under shield tunneling comprises: the system comprises a numerical analysis platform, a monitoring center and a data processing system, wherein the numerical analysis platform is used for establishing a numerical analysis model of shield tunneling, the monitoring system also comprises a monitoring point and a monitoring center which are arranged on a construction site based on a numerical analysis result and are used for collecting structural form change parameters, and the monitoring center outputs actual safety assessment which can be used for evaluating the safety of a structure according to monitoring data fed back by the monitoring point; the numerical analysis result of the numerical analysis model can be used for evaluating the primary safety assessment and the first construction parameter of the safety of the structure; and under the condition that at least one safety parameter in the actual safety assessment is within a danger threshold value, the preliminary safety assessment and the actual safety assessment are used for adjusting the first construction parameter, and the adjusted construction parameter can enable the structure to be in a controllable and/or safe state in the shield penetration construction process.

According to a preferred embodiment, the numerical analysis result can be at least used for determining the type of the arranged monitoring points and/or the relative position relationship of the monitoring points, wherein the type of the monitoring points at least comprises displacement monitoring points for monitoring the displacement of the structure, and the displacement monitoring points are determined at least based on the displacement cloud chart and/or the strain cloud chart in the numerical analysis result; and/or the spacing of the monitoring points adjacent to each other is arranged in a manner that is inversely related to the displacement values in the displacement cloud and/or the strain values in the strain cloud.

The invention provides a deformation control method of a shield underpassing structure, which at least has the following advantages:

(1) monitoring data fed back by monitoring points arranged based on numerical analysis results can be processed by a monitoring center and then output to be used for evaluating the actual safety assessment of the safety of the structure, the actual safety assessment can be mutually supplemented and mutually verified with the preliminary safety assessment, and the method is mainly used for optimizing or adjusting construction parameters according to the monitoring results and the numerical simulation results so that the structure is in a controllable and/or safe state in the shield tunneling construction process.

(2) Different monitoring points can be arranged at different positions based on the numerical analysis result, and the monitoring points are used for monitoring the positions in a targeted manner, so that the deformation monitoring of the structure is facilitated, and the construction parameters can be adjusted; and monitoring points with different monitoring densities/different monitoring quantities can be arranged according to the stress/displacement level of the numerical analysis reaction, and the key monitoring on the heavy point part is implemented.

Drawings

FIG. 1 is a schematic flow chart of a method for controlling deformation of a shield underpassing structure according to the present invention; and

fig. 2 is a schematic view of an arrangement mode of monitoring points for shield downward penetration provided by the invention.

Detailed Description

The following detailed description is made with reference to fig. 1 and 2.

Example 1

The numerical analysis model is a mathematical model which is established based on finite element method simulation and is widely applied to the engineering fields of water conservancy engineering, civil engineering, mechanical engineering, bridge engineering, metallurgical engineering and the like. The method is mainly a numerical technique for solving approximate solutions of partial differential equation boundary value problems, most practical problems are difficult to obtain accurate solutions, and finite elements not only have high calculation precision, but also can adapt to various complex shapes, so that the method becomes an effective engineering analysis means. For example, in shield tunneling, the numerical analysis method can simulate the influence of different tunneling speeds of the shield machine 300 on the disturbance of the adjacent soil body. The numerical analysis may be performed using an existing numerical analysis platform, such as a finite element analysis platform, e.g., ANSYS, ABAQUS, FLAC-3D, LS-Dyna, and MIDAS/GTS.

The present embodiment provides a method for controlling deformation of a structure 200 under a shield, as shown in fig. 1, including:

s1: and establishing a numerical analysis model of shield tunneling. The steps of the numerical analysis model mainly comprise the establishment of a physical model, the establishment of boundary conditions and grid division. The physical model comprises a tunnel geotechnical geometric model, a structural object 200 physical model, a shield machine 300 physical model and a space relation between the structural object 200 and the tunnel. The establishment of the boundary conditions comprises a mechanical model of rock and soil, a mechanical model of the shield machine 300, a mechanical model of the structure 200, tunneling parameters of shield joints and the definition of an action relation between the shield machine 300 and the rock and soil. The grid division is to perform discrete processing on the tunnel rock-soil physical model, the structural object 200 physical model and the shield machine 300 physical model.

S2: in the present invention, the numerical analysis result can be used to preliminarily evaluate the safety of the structure 200, and the influence of the construction parameters on the safety of the structure 200 can be analyzed.

S3: based on the numerical analysis result, monitoring points 100100 for acquiring parameters capable of representing deformation of the structure 200 are arranged on the construction site, and a monitoring center is established. The numerical analysis result mainly comprises a stress cloud picture, a strain cloud picture and a displacement cloud picture of rock and soil, and a stress cloud picture, a strain cloud picture and a displacement cloud picture of the structure 200. The stress cloud picture, the strain cloud picture and the displacement cloud picture of the rock and soil mainly reflect the disturbance condition of the surrounding soil body in the shield tunneling process. The stress cloud chart, the strain cloud chart and the displacement cloud chart of the structure 200 mainly reflect the problems of the inclination rate, the strength failure and the like of the structure 200 in the shield underpass process. The monitoring point 100100 and the monitoring center can be in wired communication, such as fiber-optic communication. The monitoring point 100100 and the monitoring center may also be in wireless communication, such as bluetooth communication, 4G communication, NB-loT communication, EnOcean communication, etc. The monitoring point 100100 may actually be at least one of a displacement sensor, a strain sensor, an electronic level, a house inclinometer, and other monitoring devices. For example, a certain number of displacement monitoring points 100 may be arranged at the maximum location of the displacement, while less than the number of displacement monitoring points 100 may be arranged at other locations according to the displacement cloud.

S4: the monitoring center outputs the monitoring data fed back from the monitoring point 100100, which can be used for an actual safety assessment for evaluating the safety of the structure 200. The monitoring data fed back by the monitoring point 100100 mainly includes displacement and stress. The actual safety assessment is mainly obtained by analyzing the displacement level and the stress level. The displacement level is used to analyze the settlement of the earth's surface, which is directly related to the deformation of the structure 200. The stress level may be used to analyze the stress condition of the structure 200 and may also be used to analyze the stress condition of the formation.

S5: in the construction project, if at least one safety parameter in the actual safety assessment is at a danger threshold, the preliminary safety assessment and the actual safety assessment can be combined to adjust the construction parameters, so that the structure 200 can be in a controllable and/or safe state when the shield penetrates. The preliminary safety assessment may include an analysis of the impact of various construction parameters on the deformation of the structure 200. And the actual safety evaluation is actual engineering evaluation performed through the construction parameters and the fed-back monitoring data. For example, when the displacement exceeds a danger threshold, a sensitivity parameter of the construction parameters may be adjusted for adjustment. The sensitivity parameters were derived primarily from preliminary safety assessments. The controlled state means that the deformation of the structure 200 is in a state that can be improved by a construction method such as bracing, and the safe state means that the deformation of the structure 200 is within a safety threshold set by a project.

Therefore, in the present invention, the basis of the arrangement of the monitoring points 100100 is from the result of the numerical analysis, and since the numerical analysis is established according to the actual working conditions, the arrangement of the monitoring points 100100 is not derived based on the empirical judgment. In this way, the invention also has the following advantages: 1. the monitoring point 100100 can collect the mechanical parameters of the most easily damaged part of the structure 200 based on the dangerous points of the structure 200 reflected by the stress cloud picture, the strain cloud picture and the displacement cloud picture, and is favorable for monitoring the weak link in the shield underpass process; 2. the monitoring point 100100 may adopt different types of data acquisition devices based on different types of dangerous points of the structure 200 reflected by the stress cloud chart, the strain cloud chart, and the displacement cloud chart, for example, for a portion with a large stress or a portion with a large stress concentration, the monitoring point 100100 may adopt a strain sensor, and for a portion with a large displacement, the monitoring point 100100 may adopt a displacement sensor, which mainly enables the actually acquired data to effectively monitor the type of the structure that is easily damaged according to a numerical analysis result; 3. the monitoring data fed back by the monitoring point 100100 can be processed by the monitoring center, and then, an actual safety assessment for evaluating the safety of the structure 200 is output, the actual safety assessment can complement and verify with the preliminary safety assessment, and the actual safety assessment is mainly used for optimizing or adjusting construction parameters according to a monitoring result and a numerical simulation result, so that the structure 200 is in a controllable and/or safe state in the shield tunneling construction process.

Preferably, the numerical analysis results can be used at least to determine the type of the arranged monitoring points 100 and/or the relative positional relationship of the monitoring points 100. For example, the types of monitoring points 100 include at least a displacement monitoring point 100 for monitoring displacement of the structure 200. The displacement monitoring point 100 may be a displacement sensor and/or an electronic level. The displacement monitoring points 100 may be used to monitor the horizontal displacement and/or the vertical displacement of the structure 200. As another example, the type of monitoring point 100 may also include a strain sensor for monitoring the stress of the structure 200, which can monitor the stress change of the structure 200 during shield tunneling. The arrangement position of the displacement monitoring points 100 is determined based on at least the displacement cloud and/or the strain cloud in the numerical analysis result. The displacement cloud picture is a three-dimensional picture formed by displacement values of all points in the numerical model (or a two-dimensional picture formed by selecting the displacement values of all points in a certain section in the form of a selected section in the numerical platform). The same is true. The strain cloud picture is a three-dimensional picture formed by strain values of all points in a numerical model (or a two-dimensional picture formed by selecting the strain values of all points in a certain section in the form of a selected section in a numerical platform). Therefore, the engineer can read dangerous points such as the maximum point, the larger point, the catastrophe point, and the like of the displacement value in the numerical calculation platform as the arrangement center of the displacement monitoring point 100 to arrange the displacement monitoring point 100. The monitoring intervals of the monitoring points 100 adjacent to each other are arranged in a manner that is inversely related to the displacement values in the displacement cloud and/or the strain values in the strain cloud. For example, for the location of the maximum point of the displacement value, one displacement monitoring point 100 may be arranged, and the other displacement monitoring points 100 may be arranged in line with the displacement monitoring point 100 at the maximum point, and the monitoring pitch of the adjacent displacement monitoring points 100 closer to the maximum point is smaller, while the monitoring pitch of the adjacent displacement monitoring points 100 farther from the maximum point is larger. For another example, for the position of the maximum point of the displacement value, one displacement monitoring point 100 may be arranged at the maximum point, and a plurality of layers of displacement monitoring points 100 are arranged around the displacement monitoring point 100, wherein the closer to the maximum point, the closer to the inner layer, the adjacent displacement monitoring points 100 have the smaller monitoring distance (monitoring arc), and the farther from the maximum point, the outer layer, the adjacent displacement monitoring points 100 have the larger monitoring distance (monitoring arc). In the prior art, the monitoring points 100 for monitoring the change in displacement are arranged along the tunnel axis and perpendicular to the tunnel axis. However, this method in the prior art is based on empirical judgment, and at least the following differences can be found between each kind of engineering: the spatial relationship between the structure 200 and the tunnel to be built is different, the soil around the tunnel to be built is different, and the type of the structure 200 is different. Therefore, in the conventional method of arranging the monitoring points 100 based on experience, the displacement of the dangerous part for a specific project cannot be reflected really, so that the risk of the project is increased. In this way, the invention can have at least the following advantages: 1. different monitoring points 100 can be arranged at different positions based on the numerical analysis result, and are used for monitoring the position in a targeted manner, so that the deformation of the structure 200 can be monitored, and the construction parameters can be adjusted; 2. monitoring points 100100 with different monitoring densities and different monitoring quantities can be arranged according to the stress/displacement level of the reaction of the numerical analysis, and the important monitoring on the important part is implemented.

As shield construction belongs to shallow layer drilling construction, adverse weather influence, such as rainy days, is inevitable in the construction process. The superficial formation is mostly susceptible to water content, so that the feedback data from the monitoring point 100 may be greatly changed at this stage, which is not favorable for the safety of the structure 200. For this reason, it is preferable that the monitoring frequency of the monitoring point 100 is set based on the rate of change of the feedback data with time in the case where the change of the feedback data with time of the monitoring point 100 is greater than or equal to the deformation rate threshold value set based on the numerical analysis result. In the numerical analysis model, a dynamic nonlinear simulation process is adopted, so that each cloud image is constantly changed (but the trends of the displacement cloud image, the strain cloud image and the stress cloud image are approximately unchanged within a certain tunneling time, for example, the maximum displacement point, the maximum strain point and the maximum stress point are approximately unchanged.) the deformation rate threshold set by the numerical analysis result can be obtained as follows: the ratio of the difference value of the maximum displacement value and the minimum displacement value of the maximum displacement point to the tunneling time within the certain tunneling time; or, in the certain tunneling time, the ratio of the difference value between the maximum displacement value and the average displacement value of the maximum displacement point to the tunneling time. For example, when the monitored displacement change rate is greater than or equal to the displacement change rate in the numerical analysis result, the monitoring frequency of the monitoring point 100 increases. For example, the monitoring frequency of the monitoring point 100 is 8 times/day, and if the monitored displacement change rate is greater than or equal to the displacement change rate in the numerical analysis result, the monitoring frequency of the monitoring point 100 is increased to 10 times/day or 12 times/day or more. The increased monitoring frequency depends on the rate of change of the feedback data of the monitoring point 100 over time, the greater the rate of change, the more the increased monitoring frequency. For example, if the deformation rate threshold set based on the numerical analysis result is 1mm/d, and the change rate of the feedback data of the monitoring point 100 with time is 1.1mm/d, the monitoring frequency of the monitoring point 100 will increase to 10 times/day; if the rate of change of the feedback data of the monitoring point 100 with time is 1.2mm/d, the monitoring frequency of the monitoring point 100 will increase to 12 times/day. In this way, the invention has at least the following advantages: 1. the displacement deformation rate of the rock and soil/the displacement deformation rate of the structure 200 can be determined according to actual monitoring data, so that the monitoring frequency can be increased under the condition that the displacement deformation rate/the displacement deformation rate of the structure 200 is greater than a deformation rate threshold value set by a numerical analysis result, and the monitoring strength is favorably implemented by encryption; 2. the numerical analysis result is often an analysis result for an ideal working condition, and the analysis result can set a certain evaluation index which can be used in actual construction, so that the set deformation rate threshold value comes from the numerical analysis result, the function of guiding actual engineering through numerical simulation analysis can be realized, and the mutual correspondence between the numerical analysis result and the evaluation index is facilitated.

Preferably, in the case where the distance between the shield machine 300 and the structure 200 is less than the distance threshold value set based on the numerical analysis result, the monitoring frequency of the monitoring point 100 is increased. The spacing between the shield machine 300 and the structure 200 may be defined as: the length of the line between the geometric center of the shield machine 300 and the geometric center line of the structure 200, or the length of the line between the center of gravity of the cutterhead of the shield machine 300 and the center of gravity of the structure 200, or the geometric distance between the ground plane of the structure 200 and the tunnel under construction. For example, the numerical analysis result sets a spacing threshold value to be 5 to 8 times of the radius of the tunnel under construction. For example, when the geometric distance between the ground plane of the structure 200 and the tunnel to be built is greater than 5 times the radius of the tunnel to be built, the monitoring frequency of the monitoring point 100 is 6 times/d. When the geometric distance between the ground plane of the structure 200 and the tunnel to be built is less than 5 times of the radius of the tunnel to be built, the monitoring frequency of the monitoring point 100 is 8 times/d. And/or the number of arranged monitor points 100 increases and the monitoring pitch of adjacent monitor points 100 decreases. For example, when the geometric distance between the ground plane of the structure 200 and the tunnel to be built is greater than 5 times of the radius of the tunnel to be built, the monitoring distance between the adjacent monitoring points 100 arranged in a straight line is 3-6 m. However, when the geometric distance between the ground plane of the structure 200 and the tunnel to be built is greater than 5 times of the radius of the tunnel to be built, the monitoring distance between the adjacent monitoring points 100 arranged in a straight line is 1-4 m. The shield tunneling downward penetration is an engineering event closely related to time. The spatial relationship between the shield machine 300 and the structure 200 is constantly changing over time, which can be described generally as: the shield machine 300 gradually approaches the structure 200 until the distance from the structure 200 is minimized, and then gradually moves away from the structure 200. Thus, the physical state (stress level, strain level, and position) of structure 200 is constantly changing. Therefore, the method can effectively evaluate the deformation of the structure 200 on the premise of saving engineering resources.

Preferably, the risk underpass sections are identified based on numerical analysis results and settlement control quantities of the different underpass sections. In the present invention, the lower risk wearing section can be divided into: low risk underpass sections, medium risk underpass sections, and high risk underpass sections. For example, different risk-level risk underpass sections correspond to different levels of the difference between the displacement value and the settlement control amount in the numerical analysis result. Preferably, the sedimentation control amount may be 20 mm. The corresponding difference range of the low-risk underpass section is 10-15 mm (10 mm is excluded). The corresponding difference range of the middle-risk underpass section is 5-10 mm (excluding 5 mm). The corresponding difference range of the high-risk underpass section is 0-5 mm. When the shield is penetrated to the risk penetrating section, the monitoring mode of the monitoring point 100 may be one or more of the following modes to construct a topology monitoring network:

A. the monitoring frequency of the monitoring point 100 is increased. The monitoring frequencies respectively corresponding to the low-risk underpass section, the medium-risk underpass section and the high-risk underpass section are sequentially increased. For example, when the shield machine 300 is run through a low risk run-through section, the monitoring frequency is 6 times per day. When the shield machine 300 is in a risk underpass section, the monitoring frequency is 8 times per day. When the shield machine 300 is driven down a high-risk driving-down section, the monitoring frequency is 12 times per day.

B. The number of arrangements of the monitoring points 100 is increased. The number of the monitoring arrangements respectively corresponding to the low-risk lower-penetrating section, the medium-risk lower-penetrating section and the high-risk lower-penetrating section is sequentially increased. For example, when the shield machine 300 is run through a low-risk run-through section, the number of the arrangement is 6. In the risk underpass section of the shield machine 300, the number of the arrangement is 10. When the shield machine 300 is driven down a high-risk driving section, the number of the arranged high-risk driving sections is 16.

C. The arrangement density of the monitoring points 100 is increased. The monitoring arrangement densities respectively corresponding to the low-risk underpass section, the medium-risk underpass section and the high-risk underpass section are sequentially increased. For example, when the shield machine 300 is driven to pass through a low-risk driving section, the arrangement density is 4-8 m. When the shield machine 300 is in a risk downward-penetrating section, the arrangement density is one for every 3-6 m. When the shield machine 300 is used for penetrating a high-risk downward penetrating section, the arrangement density is one for every 2-4 m.

D. The arrangement of the monitoring points 100 is changed. The specificity of the sedimentation distribution is analyzed mainly on the basis of the numerical analysis results. For example, if the sedimentation distribution is linear, it may be arranged in a line. If the sedimentation distribution is quadratic, it can be arranged in the circumferential direction with respect to the curve of the quadratic function.

The monitoring schemes of the monitoring points 100100 are arranged according to the difference between the result of the numerical analysis and the controlled amount of sedimentation, which has at least the following advantages: 1. carrying out key monitoring on key workshop sections; 2. the risk source can be identified in advance, and the key monitoring can be carried out on the risk source in the construction engineering.

Example 2

This embodiment may be a further improvement and/or a supplement to embodiment 1, and repeated contents are not described again. The preferred embodiments of the present invention are described in whole and/or in part in the context of other embodiments, which can supplement the present embodiment, without resulting in conflict or inconsistency.

Preferably, the deformation influence of the physical characteristics of the stratum around the tunnel to be built on the structure 200 is preliminarily analyzed according to the numerical analysis model. In the shield construction process, the stratum to be drilled is mostly one or a combination of more of loose soil, clay, silt, sandy soil, gravel and the like. These formations are subject to large displacements after the shield has tunneled, and most studies have shown that: formation factors are one of the more significant factors in deformation of the structure 200. Therefore, the numerical analysis result of the present embodiment is specifically analyzed for the physical properties of the formation for a specific project. One is as follows: the stratum encountered by each engineering drill is different, and the influence of each stratum parameter on the displacement needs to be analyzed. The second step is as follows: because the tunnel is of a long and narrow type, the stratum of each underpass section in each project can be different, and the influence of the stratum parameters of each underpass section on the displacement also needs to be analyzed. In this embodiment, a mechanical configuration scheme and/or a support reinforcement scheme are preliminarily formulated in combination with the controlled settlement amount. The mechanical configuration scheme mainly comprises the selection of a cutter head, the selection of a shield single guide and a panel, the selection of a grouting pump, the pipeline arrangement of the grouting pump and the like. The supporting and reinforcing scheme comprises a spray anchor support, a steel-wood support, a concrete lining, a grouting support and the like.

Therefore, the invention can select different mechanical configuration schemes and support reinforcement schemes for different projects by analyzing the numerical analysis result and the settlement control value, and also can select different mechanical configuration schemes and support reinforcement schemes for different project underpass sections of the same project, thereby being capable of avoiding the technical problem of deformation of the structure 200 caused by surface displacement caused by stratum factors in advance or reducing the risk of deformation of the structure 200 caused by surface displacement caused by stratum factors.

In this embodiment, the physical properties of the formation refer to a constitutive model of the formation, which includes at least an internal friction angle, a poisson's ratio, and/or an elastic modulus. The internal friction angle, poisson's ratio, and/or elastic modulus may be determined by sampling the formation and then inputting into a numerical analysis model.

Example 3

This embodiment may be a further improvement and/or a supplement to embodiments 1 and 2, and repeated contents are not described again. The preferred embodiments of the present invention are described in whole and/or in part in the context of other embodiments, which can supplement the present embodiment, without resulting in conflict or inconsistency.

The deformation rate threshold may be set at least as follows: and acquiring a sinking curve of the structure 200 in the process of simulating shield downward penetration based on the numerical analysis result. In the numerical analysis results, a displacement curve of the center of gravity of the study structure 200 may be obtained. And then dividing the sinking curve into an early stage sinking curve, a middle stage sinking curve and a later stage sinking curve according to the advancing path of the shield cutter head and the law of the sinking curve. The early subsidence curve corresponds to the stage when the shield cutterhead does not pass through the structure 200. The mid-term sag profile may include a period in which the shield cutterhead is passing through the structure 200, or may include a period in which part of the shield cutterhead has not passed through the structure 200 (determined primarily by calculating the rate of change of displacement of the sag profile, as determined by the inflection point in the mathematics) and/or a period in which part of the shield cutterhead has passed through the structure 200 (determined primarily by calculating the rate of change of displacement of the sag profile, as determined by the inflection point in the mathematics). The late subsidence curve corresponds to the stage when the shield cutterhead has passed the structure 200. And setting a previous deformation rate threshold value based on the previous sinking curve. And setting a medium-term deformation rate threshold value based on the medium-term subsidence curve. And setting a later deformation rate threshold value based on the later sinking curve. During actual shield tunneling, the settling rate of the structure 200 is different at each stage of the shield tunneling. Also, the settling rate of the structure 200 is the fastest during the shield traversing the structure 200. Thus, the early deformation rate threshold and the late deformation rate threshold are less than the medium deformation rate threshold. According to the mode, according to the settlement development characteristics of the structures 200 at different stages of the numerical simulation result, deformation monitoring and different protection schemes are implemented on the structures 200 in stages, and then corresponding construction parameter adjustment and protection scheme adjustment are carried out on settlement in the construction process according to the monitoring result, so that deformation control of the structures 200 at each downward-penetrating stage is effectively guaranteed.

Example 4

This embodiment may be a further improvement and/or a supplement to embodiments 1, 2, and 3, and repeated details are not repeated. The preferred embodiments of the present invention are described in whole and/or in part in the context of other embodiments, which can supplement the present embodiment, without resulting in conflict or inconsistency.

In the invention, the construction parameters at least comprise soil bin pressure, shield thrust, single-disk torque and/or tunneling speed.

Because the numerical analysis model is established in the numerical analysis platform, the soil bin pressure, the shield thrust, the single disc torque and/or the tunneling speed can be applied to the model as loads respectively, and therefore, the relevance of different soil bin pressures, shield thrust, single disc torques and/or tunneling speeds to the deformation parameters of the structure 200 can be analyzed. For example, a single factor analysis may be used to analyze the trend of the deformation parameters of the structure 200 (e.g., the amount of sinking of the structure 200) as a function of the pressure in the earth reservoir. For another example, a single factor analysis method may be used to analyze the influence trend of the shield thrust on the deformation parameters of the structure 200 (e.g., the subsidence of the structure 200). Moreover, the method may also use an orthogonal experiment principle to analyze the pressure of the soil bin, the shield thrust, the single disc torque and/or the tunneling speed to select sensitive factors affecting the deformation of the structure 200, and may be determined by using an orthogonal experiment design of 4-factor 3 level, for example. In this way, the invention can also have the following advantages: 1. the method is beneficial to identifying the sensitive factors influencing the deformation of the structure 200, and is used for guiding and making a control plan and a monitoring plan for the sensitive factors in advance; 2. when monitoring data abnormality occurs at the monitoring point 100, an adjustment plan for the sensitive factors can be deployed through key research on the sensitive factors.

Example 5

The embodiment discloses a deformation evaluation system for a shield underpassing structure 200, which can be used for realizing the monitoring methods in the embodiments 1 to 4.

The shield tunneling machine comprises a numerical analysis platform used for establishing a numerical analysis model of shield tunneling.

The evaluation system further comprises a monitoring point 100100 and a monitoring center arranged on the construction site for acquiring parameters capable of characterizing the deformation of the structure 200 based on the results of the numerical analysis.

The monitoring center outputs the monitoring data fed back from the monitoring point 100100, which can be used for an actual safety assessment for evaluating the safety of the structure 200.

The numerical analysis result of the numerical analysis model can be used for preliminary safety evaluation and first construction parameters for evaluating the safety of the structure 200.

Under the condition that at least one safety parameter in the actual safety assessment is within a danger threshold, the primary safety assessment and the actual safety assessment are used for adjusting a first construction parameter, and the adjusted construction parameter can enable the structure 200 to be in a controllable and/or safe state in the shield penetration construction process.

Preferably, the numerical analysis results can be used at least to determine the type of the arranged monitoring points 100 and/or the relative positional relationship of the monitoring points 100.

The types of the monitoring points 100 at least include displacement monitoring points 100 for monitoring the displacement of the structure 200, and the displacement monitoring points 100 are determined at least based on the displacement cloud and/or the strain cloud in the numerical analysis result. And/or

The spacing of the monitoring points 100 adjacent to each other is arranged in a manner that is inversely related to the displacement values in the displacement cloud and/or the strain values in the strain cloud.

It should be noted that the above-mentioned embodiments are exemplary, and that those skilled in the art, having benefit of the present disclosure, may devise various arrangements that are within the scope of the present disclosure and that fall within the scope of the invention. It should be understood by those skilled in the art that the present specification and figures are illustrative only and are not limiting upon the claims. The scope of the invention is defined by the claims and their equivalents.

Claims (10)

1. A method of controlling deformation of a shield underrun structure (200), comprising:

establishing a numerical analysis model of shield tunneling, wherein the numerical analysis model comprises a spatial position relation between the structure (200) and a shield tunnel, construction parameters of shield tunneling, a physical model of the structure (200) and a physical model of the shield tunnel;

obtaining characteristic parameters capable of characterizing deformation of the structure (200) based on the numerical analysis model, wherein the characteristic parameters comprise at least one of displacement of the structure (200), stress of the structure (200), displacement of rock and soil surrounding the shield tunnel and stress of the rock and soil surrounding the shield tunnel, so as to generate a preliminary safety assessment capable of being used for evaluating safety of the structure (200) based on the characteristic parameters;

arranging monitoring points (100) used for collecting parameters capable of representing deformation of a structure (200) in field construction, and establishing a monitoring center, wherein the monitoring center outputs actual safety assessment capable of being used for evaluating the safety of the structure (200) according to monitoring data fed back by the monitoring points (100);

based on the comparison result between the preliminary safety evaluation and the actual safety evaluation, adjusting the construction parameters to enable the structure (200) to be in a controllable and/or safe state in the shield tunneling process;

it is characterized in that the preparation method is characterized in that,

the monitoring point (100) is arranged in such a way that monitoring data of a weak point capable of characterizing the deformation of the structure (200) are obtained on the basis of the preliminary security assessment, so that the monitoring center can output the actual security assessment on the basis of the monitoring data at least in the case of obtaining the monitoring data of the weak point fed back by the monitoring point (100);

outputting preliminary safety assessment and construction parameters which can be used for evaluating the safety of the structure (200) based on the numerical analysis result, and under the condition that at least one safety parameter in the actual safety assessment is within a danger threshold value, adjusting the construction parameters by combining the preliminary safety assessment and the actual safety assessment, wherein the adjusted construction parameters can enable the structure (200) to be in a controllable and/or safe state in the shield penetration construction process.

2. Control method according to claim 1, characterized in that the numerical analysis result can be used at least for determining the type of arranged monitoring points (100) and/or the relative positional relationship of the monitoring points (100),

wherein the types of the monitoring points (100) at least comprise displacement monitoring points (100) for monitoring the displacement of the structure (200), and the arrangement positions of the displacement monitoring points (100) are determined at least based on the displacement cloud pictures and/or strain cloud pictures in the numerical analysis results; and/or

The monitoring distances of the monitoring points (100) adjacent to each other are arranged in a manner that is inversely related to the displacement values in the displacement cloud picture and/or the strain values in the strain cloud picture.

3. The control method according to claim 1 or 2, characterized in that in a case where a change with time of the feedback data of the monitoring point (100) is larger than or equal to a deformation rate threshold value set based on a numerical analysis result, a monitoring frequency of the monitoring point (100) is set based on a change rate with time of the feedback data;

wherein the increased monitoring frequency is dependent on the rate of change of the feedback data of the monitoring point (100) over time.

4. Control method according to one of the preceding claims, characterized in that the monitoring frequency of the monitoring point (100) is increased in case the shield machine is at a distance from the structure (200) which is smaller than a distance threshold value set on the basis of the results of the numerical analysis; and/or the arrangement number of the monitoring points (100) is increased and the monitoring distance between the adjacent monitoring points (100) is reduced;

and the distance threshold is 5 to 8 times of the radius of the tunnel to be built.

5. The control method according to one of the preceding claims, characterized in that risk underpass sections are identified based on numerical analysis results and settlement control quantities of different underpass sections, and when the shield underpass to the risk underpass sections, the monitoring mode of the monitoring points (100) constructs a topology monitoring network in the following way:

increasing the monitoring frequency of the monitoring point (100); and/or

Increasing the number of the arrangement of the monitoring points (100); and/or

Increasing the arrangement density of the monitoring points (100); and/or

Changing the arrangement mode of the monitoring points (100).

6. Control method according to one of the preceding claims, characterized in that the deformation ratio threshold value is settable at least as follows:

obtaining a sinking curve of the structure (200) in the process of simulating shield downward penetration based on the numerical analysis result,

the sinking curve can be divided into an early stage sinking curve, a middle stage sinking curve and a later stage sinking curve according to the advancing path of the shield cutter head and the law of the sinking curve,

setting a previous deformation rate threshold value based on the previous sinking curve;

setting a medium-term deformation rate threshold value based on the medium-term sinking curve;

setting a later deformation rate threshold value based on the later sinking curve;

wherein the early-stage sinking curve corresponds to the stage that the shield cutter head does not pass through the structure (200),

the mid-term subsidence curve corresponds to the stage that the shield cutterhead passes through the structure (200),

the later sinking curve corresponds to a stage when the shield cutterhead has passed through the structure (200).

7. Control method according to one of the preceding claims, characterized in that the influence of the physical properties of the ground layer surrounding the tunnel to be built on the deformation of the structure (200) is analyzed on the basis of the numerical analysis model and a mechanical configuration and/or support reinforcement solution is formulated in connection with the control of the amount of settlement,

wherein the physical property of the formation refers to a constitutive model of the formation that includes at least an internal friction angle, a poisson's ratio, and/or an elastic modulus.

8. Control method according to one of the preceding claims, characterized in that the construction parameters comprise at least the earth-reservoir pressure, the shield thrust, the single-disc torque and/or the tunneling speed;

wherein the numerical analysis model is operable to analyze the correlation of the earth-reservoir pressure, the shield thrust, the single-disc torque and/or the excavation speed with the deformation of the structure (200) such that the control method is operable to select sensitive factors affecting the deformation of the structure (200) from the earth-reservoir pressure, the shield thrust, the single-disc torque and/or the excavation speed based on the numerical analysis.

9. A system for deformation assessment of a shield underrun structure (200), comprising:

a numerical analysis platform (100) for establishing a numerical analysis model of shield tunneling,

it is characterized in that the preparation method is characterized in that,

the evaluation system also comprises a monitoring point (100) and a monitoring center which are arranged on the construction site based on the numerical analysis result and used for collecting deformation parameters capable of representing the structure (200),

the monitoring center outputs actual safety assessment which can be used for evaluating the safety of the structure (200) according to the monitoring data fed back by the monitoring point (100);

the numerical analysis results of the numerical analysis model can be used for evaluating the primary safety assessment and the first construction parameters of the safety of the structure (200);

and under the condition that at least one safety parameter in the actual safety assessment is within a danger threshold value, the preliminary safety assessment and the actual safety assessment are used for adjusting the first construction parameter, and the adjusted construction parameter can enable the structure (200) to be in a controllable and/or safe state in the shield penetration construction process.

10. Evaluation system according to one of the preceding claims, characterized in that the numerical analysis result can be used at least for determining the type of the arranged monitoring points (100) and/or the relative positional relationship of the monitoring points (100),

wherein the types of the monitoring points (100) at least comprise displacement monitoring points (100) for monitoring the displacement of the structure (200), and the displacement monitoring points (100) are determined at least based on displacement clouds and/or strain clouds in the numerical analysis result; and/or

The spacing of the monitoring points (100) adjacent to each other is arranged in a manner that is negatively correlated to the displacement values in the displacement cloud and/or the strain values in the strain cloud.

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