A shield tunnel segment safety evaluation method and system based on data monitoring

Abstract

The present application relates to the field of shield tunneling engineering technology, and in particular to a shield tunnel segment safety evaluation method and system based on data monitoring, which selects monitoring indicators of the segment to be evaluated, calculates the segment bearing capacity based on the monitoring indicators of the segment to be evaluated; analyzes the time trend and operational health status of the cross section of the segment to be evaluated based on the segment bearing capacity; compares the real-time monitored water and soil pressure of the segment to be evaluated with the design value to determine the safety of the design value of the segment to be evaluated; and configures a corresponding segment emergency reinforcement plan based on the safety of the design value of the segment to be evaluated. Based on the characteristics of the shield tunnel, the present invention uses indicators for monitoring the health status of the segment and corresponding warning values, and combines them with monitoring data to accurately evaluate the health status of the segment.

Description

Technical Field

[0001] The present application relates to the field of shield tunneling engineering technology, and in particular to a shield tunnel segment safety evaluation method and system based on data monitoring. Background Art

[0002] Monitoring is an important technical means to ensure the safety and health of shield tunnels during the construction and operation stages. The determination of its control indicators is the focus and difficulty of this work. Scientific and reasonable control of indicator values ​​can give clear warning values, providing an effective basis for the early detection and disposal of safety hazards in shield tunnels.

[0003] How to propose indicators and corresponding early warning values ​​for segment health status monitoring based on the characteristics of inverted siphon shield tunnels, and evaluate the segment health status based on monitoring data is a technical problem that needs to be solved urgently. Summary of the Invention

[0004] To achieve the above objectives, this application provides the following technical solutions:

[0005] According to a first aspect of the present invention, the present invention claims protection for a shield tunnel segment safety evaluation method based on data monitoring, comprising:

[0006] Selecting monitoring indicators of the segment to be evaluated, and calculating the segment bearing capacity based on the monitoring indicators of the segment to be evaluated;

[0007] Analyzing the time history trend and operational health status of the cross section of the segment to be evaluated based on the segment bearing capacity;

[0008] Comparing the real-time monitored water and soil pressure of the segment to be evaluated with the design value to determine the safety of the design value of the segment to be evaluated;

[0009] A corresponding segment emergency reinforcement plan is configured based on the safety of the design values ​​of the segment to be evaluated.

[0010] Furthermore, the monitoring indicators of the segments to be evaluated are selected, including:

[0011] Water and soil pressure load monitoring indicators;

[0012] Internal force monitoring indicators of reinforced concrete components;

[0013] Segment deformation monitoring indicators;

[0014] The water and soil pressure load monitoring indicator adopts the segment forward design method, uses the monitored water and soil pressure as the load borne by the segment, calculates the axial force and bending moment borne by different sections of the segment to be evaluated, and draws a bearing capacity envelope diagram based on the actual reinforced concrete parameters of the segment to be evaluated;

[0015] The internal force monitoring indicators of reinforced concrete components include lining internal force, which is calculated by arranging steel bar gauges and concrete strain gauges on the inner and outer sides of the segment to be evaluated, and back-calculating axial force and bending moment based on the monitoring values;

[0016] The segment deformation monitoring indicators are obtained by monitoring the segment deformation and settlement using a total station. No permanent deformation monitoring equipment and collection devices are set up. When the segment internal force monitoring value is abnormal, the segment deformation and settlement are measured more frequently.

[0017] Furthermore, the calculating of the segment bearing capacity based on the monitoring index of the segment to be evaluated further includes:

[0018] Calculating the first bending moment and the first axial force of the segment to be evaluated based on the water and soil pressure load monitoring index;

[0019] Calculating the second bending moment and the second axial force of the segment to be evaluated based on the concrete strain and the steel bar stress;

[0020] According to different axial compression states, eccentric compression states, and eccentric tension states, the steel bars and concrete jointly bear the bending moment and axial force of the section. Based on the axial force balance and bending moment balance equations, the cross-sectional steel reinforcement beam index of the evaluated segment is forward calculated, and the segment bearing capacity envelope diagram is solved.

[0021] Furthermore, the analyzing of the time history trend and operational health status of the cross section of the segment to be evaluated based on the segment bearing capacity further includes:

[0022] When analyzing the time-history trend of the section of the segment to be evaluated based on the segment bearing capacity, obtaining water and soil pressure monitoring data and concrete strain monitoring data of the section of the segment to be evaluated;

[0023] Analyzing the water and soil pressure monitoring data and the concrete strain monitoring data to obtain a time history trend of the cross section of the segment to be evaluated;

[0024] The water and soil pressure monitoring data includes at least: water and soil pressure during the construction phase and long-term water and soil pressure;

[0025] The concrete strain monitoring data includes at least: the compressive state of the pipe segment section;

[0026] The relationship between the outer and inner compressive stresses at various locations on the segment;

[0027] Variation trend of ring concrete compressive strain with time.

[0028] Furthermore, analyzing the time history trend and operational health status of the cross section of the segment to be evaluated based on the segment bearing capacity further includes:

[0029] When analyzing the operational health status of the section of the segment to be evaluated based on the segment bearing capacity, obtaining an axial force and bending moment distribution diagram, a time-varying trend diagram of the axial force and bending moment, a bearing capacity envelope diagram based on concrete strain, and a bearing capacity envelope diagram based on water and soil pressure of the section of the segment to be evaluated;

[0030] The operational health status of the section of the pipe segment to be evaluated is obtained by analyzing the axial force and bending moment distribution diagram of the section of the pipe segment to be evaluated, the axial force and bending moment change trend diagram over time, the bearing capacity envelope diagram based on concrete strain, and the bearing capacity envelope diagram based on water and soil pressure.

[0031] Furthermore, the step of comparing the real-time monitored water and soil pressure of the segment to be evaluated with the design value to determine the safety of the design value of the segment to be evaluated further includes:

[0032] Design water and soil pressure values ​​and lateral pressure coefficient values ​​for lateral pressure tests;

[0033] Comparing the monitored water and soil pressure with the design value, the lateral earth pressure coefficient obtained by monitoring is greater than the design value, and the design value safety of the design load value is high.

[0034] Furthermore, the segment emergency reinforcement plan corresponding to the safety of the design value of the segment to be evaluated further includes:

[0035] During the construction process, if the monitoring data reaches the warning standard or the measured deformation value is greater than 2 / 3 of the allowable deformation, an alarm report should be sent;

[0036] When the tunnel structure shows deformation, cracks, water leakage, or the shield segment clearance convergence deformation rate is greater than 2mm / d, and the cumulative clearance convergence deformation value is greater than 10mm, the deep buried shield tunnel segment reinforcement treatment shall be carried out.

[0037] According to a second aspect of the present invention, the present invention claims protection for a shield tunnel segment safety assessment system based on data monitoring, comprising:

[0038] one or more processors;

[0039] A memory having one or more programs stored thereon, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the shield tunnel segment safety evaluation method based on data monitoring.

[0040] The present application relates to the field of shield tunneling engineering technology, and in particular to a shield tunnel segment safety evaluation method and system based on data monitoring, which selects monitoring indicators of the segment to be evaluated, calculates the segment bearing capacity based on the monitoring indicators of the segment to be evaluated; analyzes the time trend and operational health status of the cross section of the segment to be evaluated based on the segment bearing capacity; compares the real-time monitored water and soil pressure of the segment to be evaluated with the design value to determine the safety of the design value of the segment to be evaluated; and configures a corresponding segment emergency reinforcement plan based on the safety of the design value of the segment to be evaluated. Based on the characteristics of the shield tunnel, the present invention uses indicators for monitoring the health status of the segment and corresponding warning values, and combines them with monitoring data to accurately evaluate the health status of the segment. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A workflow diagram of a shield tunnel segment safety evaluation method based on data monitoring as claimed in an embodiment of the present application;

[0042] Figure 2 A schematic diagram of micro-segmented internal forces of a shield tunnel segment safety evaluation method based on data monitoring as claimed in an embodiment of the present application;

[0043] Figure 3 A schematic diagram of coordinate conversion at an inflection point of a shield tunnel segment safety evaluation method based on data monitoring as claimed in an embodiment of the present application;

[0044] Figure 4 A data monitoring-based shield tunnel segment safety evaluation method claimed for protection in an embodiment of the present application calculates the bearing capacity envelope diagram of concrete components according to the forward structural design theory. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0046] The terms "first," "second," and "third" in this application are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features specified as "first," "second," or "third" may explicitly or implicitly include at least one of such features. In the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are intended only to illustrate the relative positional relationships and movement of components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly. Furthermore, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements and may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to such process, method, product, or apparatus.

[0047] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0048] Inverted siphon shield tunnels are deep-buried, high-water-pressure shield tunnels with large cross-sections and complex load patterns. It is particularly important to rationally calculate and evaluate the water-soil pressure and internal forces of the lining structure. To understand the actual stress and deformation state of the tunnel, on-site measurements of the earth pressure, internal forces, and deformation of the shield tunnel are often performed during engineering projects to evaluate the safety and stability of the structure.

[0049] According to the first embodiment of the present invention, the present invention claims a shield tunnel segment safety evaluation method based on data monitoring, referring to Figure 1 ,include:

[0050] Selecting monitoring indicators of the segment to be evaluated, and calculating the segment bearing capacity based on the monitoring indicators of the segment to be evaluated;

[0051] Analyzing the time history trend and operational health status of the cross section of the segment to be evaluated based on the segment bearing capacity;

[0052] Comparing the real-time monitored water and soil pressure of the segment to be evaluated with the design value to determine the safety of the design value of the segment to be evaluated;

[0053] A corresponding segment emergency reinforcement plan is configured based on the safety of the design values ​​of the segment to be evaluated.

[0054] Furthermore, the monitoring indicators of the segments to be evaluated are selected, including:

[0055] Water and soil pressure load monitoring indicators;

[0056] Internal force monitoring indicators of reinforced concrete components;

[0057] Segment deformation monitoring indicators;

[0058] The water and soil pressure load monitoring indicator adopts the segment forward design method, uses the monitored water and soil pressure as the load borne by the segment, calculates the axial force and bending moment borne by different sections of the segment to be evaluated, and draws a bearing capacity envelope diagram based on the actual reinforced concrete parameters of the segment to be evaluated;

[0059] The internal force monitoring indicators of reinforced concrete components include lining internal force, which is calculated by arranging steel bar gauges and concrete strain gauges on the inner and outer sides of the segment to be evaluated, and back-calculating axial force and bending moment based on the monitoring values;

[0060] The segment deformation monitoring indicators are obtained by monitoring the segment deformation and settlement using a total station. No permanent deformation monitoring equipment and collection devices are set up. When the segment internal force monitoring value is abnormal, the segment deformation and settlement are measured more frequently.

[0061] Among them, in this embodiment, the segment structure is the main load-bearing structure of the shield tunnel. The strength, deformation and stability characteristics of the segment structure have an important impact on the long-term safe use of the shield tunnel. The stress characteristics of the segment structure are the main external force factors that determine the deformation and long-term stability of the segment. For shield tunnels, due to the complex geological conditions and environmental conditions, and the construction factors also have a significant impact on the stress of the segment, the stress characteristics of the segment are often more complex.

[0062] External loads are the most important factors affecting the strength, deformation, and stability of segment structures. However, it is difficult to directly use the magnitude of the load as an indicator of whether a segment is operating safely. This is because for circular segments, if subjected to a uniformly distributed load, each section is in an axially compressed or near-axially compressed state. The structure can withstand a considerable uniformly distributed load. However, the water and soil pressure on the segments often tends to be larger at the top and bottom and smaller on the sides, resulting in an unbalanced bending moment in the segment and an eccentrically compressed state. Therefore, the magnitude of water and soil pressure cannot directly determine the safety status of the segment. The magnitude and distribution of water and soil pressure are the factors that determine the stress on the segment.

[0063] The forward design method of the segment is adopted. The monitored water and soil pressure is used as the load borne by the segment. The axial force and bending moment borne by different sections of the segment are calculated. The bearing capacity envelope diagram is drawn according to the actual reinforced concrete parameters of the segment. The health status of the segment is judged based on the monitored values ​​of water and soil pressure.

[0064] On-site monitoring of tunnel lining internal forces is an effective and direct method for understanding shield segment performance. By monitoring the internal forces, the axial forces and bending moments acting on the lining segments can be understood and calculated. These can then be compared with the stress characteristics under design conditions, providing a basis for assessing the health of the segments. In this embodiment, segment internal force monitoring is performed using rebar gauges and concrete strain gauges, placed on the inside and outside of the segments. The axial forces and bending moments are calculated based on the monitored values.

[0065] Domestic technical specifications provide control requirements for calculating shield tunnel segment deformation. Many local standards stipulate that shield tunnel lining deformation limits are: diameter deformation of 2% to 3%D (D is the tunnel's outer diameter), maximum joint deformation of 2 to 4 mm, and maximum misalignment of 4 to 6 mm. The following table lists the control indicators for segment deformation and settlement in this embodiment. When monitoring data reaches the warning standard or the measured deformation value exceeds 2 / 3 of the allowable deformation, an alert report should be issued.

[0066] Since deformation and settlement mainly occur during the shield segment construction period, a total station is used to monitor the deformation and settlement of the segments during the construction period. No permanent deformation monitoring equipment and collection devices are set up. When the internal force monitoring values ​​of the segments are abnormal, the deformation and settlement of the segments are measured more frequently. Table 1 shows the control values ​​of the vertical displacement and clearance convergence monitoring items of the tunnel segment structure.

[0067] Table 1 Control values ​​of tunnel segment structure vertical displacement and clearance convergence monitoring items

[0068]

[0069] Furthermore, the calculating of the segment bearing capacity based on the monitoring index of the segment to be evaluated further includes:

[0070] Calculating the first bending moment and the first axial force of the segment to be evaluated based on the water and soil pressure load monitoring index;

[0071] Calculating the second bending moment and the second axial force of the segment to be evaluated based on the concrete strain and the steel bar stress;

[0072] According to different axial compression states, eccentric compression states, and eccentric tension states, the steel bars and concrete jointly bear the bending moment and axial force of the section. Based on the axial force balance and bending moment balance equations, the cross-sectional steel reinforcement beam index of the evaluated segment is forward calculated, and the segment bearing capacity envelope diagram is solved.

[0073] The first bending moment and first axial force are calculated based on the water and soil pressure acting on the segment. Using the forward design method based on environmental indicators, the segment's bending moment and axial force are solved. These are then compared with the segment's inherent bending moment and axial force resistance characteristics to determine the segment's safety status.

[0074] The second bending moment and the second axial force directly reflect the stress state of the segment. The microscopic concrete strain and steel stress are reversely converted into the macroscopic bending moment and axial force of the segment, and then compared with the bending moment and axial force resistance characteristics of the segment itself to evaluate the operating status of the segment.

[0075] In this embodiment, the calculation of the first bending moment and the first axial force of the segment to be evaluated based on the water and soil pressure load monitoring index specifically includes:

[0076] The tangential load q acts on the micro-segment ds of the lining t and radial load q n , the signs of internal forces and displacements are as follows Figure 2 As shown, the axial force T is positive in tension, the shear force Q is positive in counterclockwise rotation around the calculation section, the bending moment M is positive in tension on the inner side, the normal displacement v is positive in the normal direction outside the body, the tangential displacement u is positive in the normal direction outward to the right, and the angular displacement is positive in counterclockwise rotation.

[0077] Assuming that the elastic resistance is proportional to the displacement in the normal direction of the lining surface, the following equations can be obtained based on the static equilibrium and deformation coordination conditions on the micro-segment (omitting the advanced micro-segments):

[0078] ;

[0079] Where:

[0080] T - axial force of the calculated section of the lining (kN), with tension as positive;

[0081] ds - micro-segmentation of lining (m);

[0082] k - arch axis curvature;

[0083] Q - shear force of the lining calculation section (kN), with counterclockwise rotation as positive;

[0084] q - tangential load density distributed along the axis (kN / m);

[0085] K - elastic resistance coefficient of surrounding rock (MN / m 2 );

[0086] v - normal displacement of the calculated section of the lining (m);

[0087] h - calculated height of surrounding rock (m);

[0088] q n --Normal load strength of the calculated lining section (kN / m);

[0089] M - bending moment of the calculated section of the lining (kN·m), with the inner side in tension as positive;

[0090] u - tangential displacement of the calculated section of the lining (m);

[0091] E - elastic modulus of lining material (MPa);

[0092] F - cross-sectional area of ​​lining calculation section (m 2 );

[0093] α is a constant related to the arch cross section;

[0094] G - shear elastic modulus (MPa);

[0095] ψ - angular displacement of the calculated section of the lining (radians);

[0096] J - Moment of inertia of lining calculation section (m 4 );

[0097] Considering the boundary conditions at the beginning and end, it can be written in matrix form as:

[0098] ;

[0099] Where:

[0100] X - the total unknown element vector when solving;

[0101] A - a matrix containing various parameters of lining materials;

[0102] P - load density vector;

[0103] ds - micro-segmentation of lining (m);

[0104] C - calculate the boundary matrix of the starting point;

[0105] Ignore the shear displacement term and multiply the tangential displacement u, normal displacement v, and angular displacement ψ by the elastic modulus E, then the X, A, and P matrices are:

[0106] ;

[0107] ;

[0108] ;

[0109] Where:

[0110] T - axial force of the calculated section of the lining (kN), with tension as positive;

[0111] Q - shear force of the lining calculation section (kN), with counterclockwise rotation as positive;

[0112] M - bending moment of the calculated section of the lining (kN·m), with the inner side in tension as positive;

[0113] ψ - angular displacement of the calculated section of the lining (radians);

[0114] U′――equal to Eu;

[0115] V′――equal to Ev;

[0116] ψ′ - equal to Eψ;

[0117] q t -- Tangential load strength of the calculated lining section (kN / m);

[0118] q n --Normal load strength of the calculated lining section (kN / m);

[0119] k - arch axis curvature;

[0120] h - calculated height of surrounding rock (m);

[0121] K - elastic resistance coefficient of surrounding rock (MN / m 2 );

[0122] E - elastic modulus of lining material (MPa);

[0123] F - cross-sectional area of ​​lining calculation section (m 2 );

[0124] J - Moment of inertia of lining calculation section (m 4 ).

[0125] C and D have the following situations:

[0126] (1) Symmetric point: Q = 0, u = 0, ψ = 0, the boundary matrix is:

[0127] ;

[0128] (2) Hinge point: M = 0, u = 0, v = 0, the boundary matrix is:

[0129] ;

[0130] (3) Fixed end: u = 0, v = 0, ψ = 0, the boundary matrix is:

[0131] ;

[0132] (4) Elastic fixed end: T = Kd n U, M = KJ n ψ, Q = 0, the boundary matrix is:

[0133] ;

[0134] Where:

[0135] d n - Thickness of the support end (m);

[0136] J n - Sectional moment of inertia at the end (m 4 ).

[0137] A stepwise approximation of the elastic resistance distribution is used, that is, first assuming that no surrounding rock resistance is acting at each point. When the calculated displacement direction of a certain point is inconsistent with the assumed resistance distribution, the point is re-assumed to have resistance acting and the calculation continues. This assumption of resistance is repeated until the assumed resistance distribution is consistent with the calculated displacement direction. In this way, h in the A matrix is ​​known each time the solution is solved, and the system of equations becomes a linear system. The Runge-Kutta method is used to solve the differential equations, as follows:

[0138] ;

[0139] Where:

[0140] X n+1 --The total unknown element vector at the n+1th infinitesimal segment when solving;

[0141] G n --The recursive auxiliary matrix derived by Runge-Kutta method;

[0142] X n --The unknown element vector at the nth infinitesimal segment when solving;

[0143] H n --The recursive auxiliary matrix derived by Runge-Kutta method;

[0144] δ - step length;

[0145] During the calculation process, the lining is divided into several structural segments for calculation. For example, the circular arch straight wall lining is divided into three structural segments: base plate, straight wall, and top arch. The length of each structural segment is divided by the number of interactive calculation segments to obtain the unit length, which is the step length δ. For straight structural segments, the step length δ is the unit length; for arc-shaped structural segments, the step length δ is the unit arc length.

[0146] G n 、H n The calculation process is as follows:

[0147] ;

[0148] ;

[0149] ;

[0150] ;

[0151] ;

[0152] ;

[0153] ;

[0154] ;

[0155] ;

[0156] ;

[0157] ;

[0158] ;

[0159] Where:

[0160] I - Moment of inertia of lining calculation section (m 4 );

[0161] β j --Coefficient constants in the derivation process of Runge-Kutta method;

[0162] G j - The intermediate matrix of Runge-Kutta recursion;

[0163] G j-1 - The intermediate matrix of Runge-Kutta recursion;

[0164] - the length of the microelement segment;

[0165] A j ——The product of the initial A matrix and the total step length;

[0166] α j - The intermediate constant in the derivation process of Runge-Kutta method, whose value is determined by j;

[0167] P j ——Load density vector at segment j;

[0168] G 0 ——G matrix of the initial segment;

[0169] H j ——H matrix at segment j;

[0170] H 0 ——H matrix of the initial segment;

[0171] A - a matrix containing various parameters of lining materials;

[0172] S n --Total step length at segment n;

[0173] j ——The length of the infinitesimal segment at the jth segment;

[0174] α1 - the intermediate constant in the derivation process of Runge-Kutta method, which is 1 / 2;

[0175] α2 - the intermediate constant in the derivation process of Runge-Kutta method, which is 1 / 2;

[0176] α3 - the intermediate constant in the derivation process of Runge-Kutta method, the size is 1 / 2;

[0177] α4 - the intermediate constant in the derivation process of Runge-Kutta method, the size is 1;

[0178] β1 - the coefficient constant of the Runge-Kutta method derivation process, which is 1 / 6;

[0179] β2 - the coefficient constant of the Runge-Kutta method derivation process, which is 1 / 3;

[0180] β3 - the coefficient constant of the Runge-Kutta method derivation process, which is 1 / 3;

[0181] β4 - the coefficient constant of the Runge-Kutta method derivation process, the size is 1 / 6;

[0182] r1 - the intermediate constant in the derivation process of Runge-Kutta method, the size is 0;

[0183] r2 - the intermediate constant in the derivation process of Runge-Kutta method, which is 1 / 2;

[0184] r3 - the intermediate constant in the derivation process of Runge-Kutta method, which is 0;

[0185] r4 - the intermediate constant in the derivation process of Runge-Kutta method, the size is 1 / 2;

[0186] - the step size of the infinitesimal segment;

[0187] 1 - the cumulative step size when j is 1 is 0;

[0188] 2 - the cumulative step size when j is 2 is 1 / 2;

[0189] 3 - the cumulative step size when j is 3 is 1 / 2;

[0190] 4 - The cumulative step size when j is 4 is;

[0191] After the equations are linearized, G in the formula n That is, it has nothing to do with the solution, so X n Available initial parameters X 0 After deduction and substituting the boundary conditions of the starting point and the end point, we can get X 0 The system of equations is as follows:

[0192] ;

[0193] Where:

[0194] C - starting point boundary matrix;

[0195] D - endpoint boundary matrix;

[0196] X 0 --The unknown element matrix at the starting point;

[0197] D m - A sixth-order square matrix, derived recursively by the Runge-Kutta method;

[0198] F m - The matrix derived recursively by the Runge-Kutta method;

[0199] D m 、F m is defined as follows:

[0200] ;

[0201] ;

[0202] ;

[0203] Where:

[0204] X m --Calculate the X value of the end point;

[0205] X0 - the X value of the calculation starting point;

[0206] D n+1 -- auxiliary matrix D at segment n+1;

[0207] D n -- auxiliary matrix D at segment n;

[0208] D 0 - The auxiliary matrix D at the initial position;

[0209] G n - the auxiliary matrix derived by the Runge-Kutta method at the nth segment;

[0210] F n+1 --The auxiliary matrix of segment n+1 is derived by the Runge-Kutta method;

[0211] F n --The auxiliary matrix at the nth segment is derived by the Runge-Kutta method;

[0212] F 0 - auxiliary matrix of the initial segment;

[0213] H n - the auxiliary matrix derived by the Runge-Kutta method at the nth segment;

[0214] When the above initial parameter method is used for recursive solution, there are axis turning points at the connection between the bottom plate and the side wall, the side wall and the top arch, and the arc and the arc. Therefore, in addition to distinguishing the two connected parts of the A matrix and the P matrix, when recursively solving D m 、F m and X m In order to ensure the internal force balance and displacement continuity at the inflection point, a connection matrix should be introduced at the inflection point.

[0215] This embodiment takes the section from the side wall to the top arch in a circular arch straight wall as an example. Figure 3 :

[0216] The coordinate transformation from the side wall to the top arch is actually a clockwise rotation of the local coordinate system by β = 90°~α, where α is the semi-center angle of the top arch. The transformation matrix for the clockwise rotation of the local coordinate system by β is as follows:

[0217]

[0218] Calculating the second bending moment and the second axial force of the segment to be evaluated based on the concrete strain and the steel bar stress includes:

[0219] There are three main methods for calculating the internal forces of shield segments based on the measured steel bar stress and concrete strain, namely the eccentric short column method proposed by Zhang Houmei, the thin shell method proposed by Zhong Xiaochun, and the simplified algorithm proposed by Emilio Bilotta.

[0220] This embodiment uses the thin shell method to calculate the internal force of the shield segment as a bearing capacity monitoring indicator. For sections where both steel bar gauges and concrete strain gauges are laid out, the eccentric short column method is used to verify the axial force and bending moment.

[0221] In the eccentric short column method, the tunnel lining is considered as an eccentrically compressed short column, taking into account the role of reinforcement;

[0222] The stress-strain relationship of steel bars is linear;

[0223] The stress-strain relationship of concrete is linear or nonlinear;

[0224] The calculation formula is:

[0225] ;

[0226] Where:

[0227] N - axial force (KN);

[0228] M - bending moment (KN·m);

[0229] A - cross-sectional area of ​​the component (m 2 );

[0230] h - the height of the component (m);

[0231] b - width of the component (m);

[0232] A' S1 、A' S2 ——The cross-sectional area of ​​the steel bars at both ends (m²);

[0233] σ c1 , σ c2 ——The concrete compressive stress at both ends (KN / m²);

[0234] σ s1 , σ s2 ——Respectively, the compressive stress of the steel bars at both ends (KN / m²);

[0235] n 1、 n2 - the number of inner and outer steel bars;

[0236] p 1、 p2 - concentrated force of inner and outer reinforcement (KN);

[0237] α 、 α′ - the distance from the steel bar resultant point to the edge (m);

[0238] Reinforcement is ignored in the thin shell method;

[0239] The stress-strain relationships of both steel and concrete are linear;

[0240] The calculation formula is:

[0241] ;

[0242] Where:

[0243] N - axial force (KN);

[0244] M - bending moment (KN·m);

[0245] E c - Elastic modulus of concrete (KN / m 3 );

[0246] b - width of the component (m);

[0247] h - the height of the component (m);

[0248] u - Poisson's ratio;

[0249] α, α′ - the distance from the combined force point of the steel bars at both ends to the edge (m);

[0250] 1. 2――The strains at both ends of the concrete member;

[0251] According to different axial compression states, eccentric compression states, and eccentric tension states, the steel bars and concrete jointly bear the bending moment and axial force of the section, and based on the axial force balance and bending moment balance equations, the cross-sectional steel reinforcement beam index of the segment to be evaluated is forward calculated, and the segment bearing capacity envelope diagram is solved, which also includes:

[0252] When designing segments or tunnel linings, steel is considered to be subjected to both tension and compression, while concrete is considered to be subjected to compression. If the section is subjected to axial compression, the steel and concrete share the compressive stress. Under eccentric compression or eccentric tension, the steel and concrete share the bending moment and axial force of the section, satisfying the equations for axial force and moment equilibrium. Therefore, using the theoretical method of forward cross-sectional reinforcement calculation for reinforced beams in structural design, solving the segment capacity envelope diagram is more complex than if the segment were treated as a plain concrete structure. The following are the reinforcement formulas for reinforced concrete components under different load states, according to the "Code for Design of Hydraulic Concrete Structures" (SL 191-2008), specifically for the combined load-bearing of concrete and steel.

[0253] 1. Axial compression state

[0254] For axial compression, the reinforcement calculation formula is as follows, and both concrete and steel bars are considered to resist compression.

[0255] ;

[0256] Where:

[0257] ——Cross-sectional area of ​​steel bars on both sides (mm 2 );

[0258] K—Bearing capacity safety factor.

[0259] N——axial pressure design value (N);

[0260] A——Component cross-sectional area (mm 2 );

[0261] ——Cross-sectional area of ​​compression steel bar (mm 2 );

[0262] ——Design value of concrete axial compressive strength (N / mm 2 );

[0263] ——Design value of compressive strength of steel bar (N / mm 2 );

[0264] When the longitudinal reinforcement ratio is greater than 3%, the concrete area A in the formula is the net cross-sectional area A. n ,Right now: ;

[0265] 2. Slightly eccentric compression state

[0266] The compressive bearing capacity of the positive section of a rectangular cross-section member with small eccentric compression is calculated. The near-side steel bars and concrete are in compression, and the far-side steel bars are also in compression.

[0267] ;

[0268] ;

[0269] Where:

[0270] ——Cross-sectional area of ​​the steel bar on the side away from the axial pressure (mm 2 );

[0271] ——Cross-sectional area of ​​the steel bar on the axial pressure side (mm 2 );

[0272] K - bearing capacity safety factor;

[0273] ——Cross-section height (mm);

[0274] ——Effective height of the cross section (mm);

[0275] ——Effective height of the cross section (mm);

[0276] b——section width (mm), take 1000mm;

[0277] ——Calculated height of compression zone (mm);

[0278] ——Design value of compressive strength of steel bar (N / mm 2 );

[0279] ——Stress of steel bars on the side away from axial pressure (N / mm 2 );

[0280] ——The distance between the axial pressure point and the reasonable point of the longitudinal reinforcement on the compression side or the side with less compression ;

[0281] - the distance from the resultant force point of the longitudinal reinforcement on the tensile side or the side with less compression to the edge (mm);

[0282] ——The distance from the resultant force point of the longitudinal reinforcement on the side with greater compression to the near edge of the section (mm);

[0283] 3. Large eccentric compression state

[0284] The simplified diagram for calculating the compressive bearing capacity of the positive section of a rectangular cross-section member subjected to large eccentric compression is the same as that of the member subjected to large eccentric compression. During the calculation, the near-side steel bars and concrete are in compression, but the far-side steel bars are also in tension.

[0285] The asymmetric reinforcement under large eccentric compression is calculated according to the following formula:

[0286] ;

[0287] ;

[0288] Where:

[0289] ——Cross-sectional area of ​​the steel bar on the side away from the axial pressure (mm 2 );

[0290] ——Cross-sectional area of ​​the steel bar on the axial pressure side (mm 2 );

[0291] K - bearing capacity safety factor;

[0292] ——Cross-section height (mm);

[0293] ——Cross-section height (mm);

[0294] ——Effective height of the cross section (mm);

[0295] b——section width (mm), take 1000mm;

[0296] ——Calculated height of compression zone (mm);

[0297] ——Design value of concrete axial compressive strength (N / mm+);

[0298] ——Design value of compressive strength of steel bar (N / mm 2 );

[0299] ——Design value of longitudinal reinforcement tensile strength (N / mm 2 );

[0300] ——The distance between the axial pressure point and the reasonable point of the longitudinal reinforcement on the compression side or the side with less compression ;

[0301] ——The distance from the longitudinal reinforcement force point on the tensile side or the side with less compression to the near edge of the section (mm);

[0302] ——The distance from the force point of the longitudinal reinforcement on the side with greater compression to the near edge of the section (mm).

[0303] 4. Axial tension state

[0304] Axial tension asymmetric reinforcement is calculated according to the following formula:

[0305] ;

[0306] Where:

[0307] ——Cross-sectional area of ​​steel bars on both sides (mm 2 );

[0308] K - bearing capacity safety factor;

[0309] N——design value of axial tension (KN);

[0310] ——Design value of longitudinal reinforcement tensile strength (N / mm 2 ).

[0311] 5. Slightly eccentric tension state

[0312] The axial tension N acts on a slightly eccentric tension member between the respective resultant points of the longitudinal reinforcements on both sides. When calculating the reinforcement, both the inner and outer reinforcements are in tension, and the tensile stress on the concrete is not considered.

[0313] ;

[0314] ;

[0315] Where:

[0316] ——Cross-sectional area of ​​the steel bar on the side close to the axial tension (mm 2 );

[0317] ——Cross-sectional area of ​​the steel bar on the side away from the axial tension (mm 2 );

[0318] K——For SL191, it is the bearing capacity safety factor; for NB / T11011, it is the concrete structure coefficient.

[0319] ——Effective height of the section ;

[0320] ——The distance from the tensile side longitudinal reinforcement force point to the near edge of the section .

[0321] 6. Large eccentric tension state

[0322] For a rectangular cross-section large eccentric tension member where the axial tensile force N does not act between the respective resultant force points of the longitudinal reinforcements on both sides, the tensile bearing capacity of the positive section should conform to the following formula. In this state, the distal reinforcement and part of the concrete are in compression, and the proximal reinforcement is in tension.

[0323] ;

[0324] ;

[0325] ;

[0326] ;

[0327] Where:

[0328] ——Cross-sectional area of ​​the steel bar on the side close to the axial tension (mm 2 );

[0329] ——Cross-sectional area of ​​the steel bar on the side away from the axial tension (mm 2 );

[0330] K - bearing capacity safety factor;

[0331] ——Design value of compressive strength of steel bar (N / mm 2 );

[0332] ——Design value of longitudinal reinforcement tensile strength (N / mm 2 );

[0333] ——Design value of concrete axial compressive strength (N / mm 2 );

[0334] b——section width (mm), take 1000mm;

[0335] ——Calculated height of compression zone (mm);

[0336] ——The distance between the point of axial tension application and the point of resultant force of the longitudinal reinforcement on the tension side (mm);

[0337] ——Distance from the point of application of axial tension to the center of gravity of the cross section (mm);

[0338] ——Cross-section height (mm);

[0339] ——Effective height of the cross section (mm);

[0340] ——The axial pressure eccentricity increase coefficient considering the influence of the second-order effect in the eccentric pressure construction is taken as 1.0;

[0341] ——Distance from the tension side longitudinal reinforcement force point to the near edge of the section (mm);

[0342] ——Distance from the force point of the longitudinal reinforcement on the compression side to the near edge of the section (mm).

[0343] According to the above-mentioned calculation formulas for the bearing capacity of reinforced concrete under axial compression, small eccentric compression, large eccentric compression, axial tension, small eccentric tension and large eccentric tension, when the segment concrete parameters and reinforcement parameters are known, the bearing capacity envelope curve is drawn as follows: Figure 4 As shown, it can be seen that after considering the compressive stress of the steel bars, the bearing capacity envelope is greatly improved compared with the calculation according to plain concrete components.

[0344] Furthermore, the analyzing of the time history trend and operational health status of the cross section of the segment to be evaluated based on the segment bearing capacity further includes:

[0345] When analyzing the time-history trend of the section of the segment to be evaluated based on the segment bearing capacity, obtaining water and soil pressure monitoring data and concrete strain monitoring data of the section of the segment to be evaluated;

[0346] Analyzing the water and soil pressure monitoring data and the concrete strain monitoring data to obtain a time history trend of the cross section of the segment to be evaluated;

[0347] The water and soil pressure monitoring data includes at least: water and soil pressure during the construction phase and long-term water and soil pressure;

[0348] The concrete strain monitoring data includes at least: the compressive state of the pipe segment section;

[0349] The relationship between the outer and inner compressive stresses at various locations on the segment;

[0350] Variation trend of ring concrete compressive strain with time.

[0351] In this embodiment, the time history trend is analyzed based on the test data of the LQS4+807.8 section (section 3, 3972 rings), including:

[0352] Water and soil pressure during the construction phase: Measurement points were arranged according to the location of the earth pressure gauges: one earth pressure gauge was placed in each of Blocks B1 (Section 3), B1 (Section 6), B3 (Section 9), L2 (Section 12), and L2 (Section 16). The temporal evolution of the ground pressure acting on the segments during construction gradually increased as the test segments were released from the ring and entered the ground, and the shield machine moved away. Affected by the shield tunneling state and the simultaneous grouting process, the ground pressure fluctuated dramatically during the shield tunneling phase. When the shield was stopped, the water and soil pressure gradually increased. The earth pressure acting on the segments was most significantly affected when the segments were near the shield tail. As the segments moved away from the shield tail, the impact of the shield construction process on the earth pressure decreased. During the shield construction phase (5:45 on May 15, 2022), the soil pressure was distributed relatively evenly around the tunnel, ranging from 0.3 to 0.4 MPa, which was basically the same as the shield synchronous grouting pressure.

[0353] Long-term Soil and Water Pressure: The long-term variation of soil pressure acting on the segments is shown in the figure. The soil pressure on the five segments generally shows a trend of increasing, then decreasing, and then increasing again. As of April 2024, monitored soil and water pressures in segments L1, B1, and L2 ranged from 0.5 to 0.65 MPa, an increase of 0.2 to 0.3 MPa compared to May 2022, when the segments were installed. The soil and water pressures were relatively uniform across all sections, and the lateral soil pressure reduction factor ranged from 0.8 to 1.0.

[0354] Concrete strain monitoring data: Among the concrete strain monitoring sections, Sections 1 to 5 are monitored from the top to the bottom, respectively. (1) The entire section of the segment is in a compressive state; (2) At the top of the segment, the compressive stress on the outside is greater than that on the inside; at the waist of the segment, the compressive stress on the inside is greater than that on the outside, and the whole presents a "flattened" stress state. (3) The strain of the concrete in this ring tends to be stable overall, and the compressive strain increases slightly over time.

[0355] Furthermore, analyzing the time history trend and operational health status of the cross section of the segment to be evaluated based on the segment bearing capacity further includes:

[0356] When analyzing the operational health status of the section of the segment to be evaluated based on the segment bearing capacity, obtaining an axial force and bending moment distribution diagram, a time-varying trend diagram of the axial force and bending moment, a bearing capacity envelope diagram based on concrete strain, and a bearing capacity envelope diagram based on water and soil pressure of the section of the segment to be evaluated;

[0357] The operational health status of the section of the pipe segment to be evaluated is obtained by analyzing the axial force and bending moment distribution diagram of the section of the pipe segment to be evaluated, the axial force and bending moment change trend diagram over time, the bearing capacity envelope diagram based on concrete strain, and the bearing capacity envelope diagram based on water and soil pressure.

[0358] In this embodiment, taking the health status of section LQS4+807.8 (section 3, ring 3972) as an example, obtaining its operational health status includes:

[0359] Axial force and bending moment distribution diagram: In the axial force and bending moment distribution diagram of different points obtained by concrete strain calculation from January to April 2024 in ring 3972, (1) all sections of the ring segment are in a compression state (there is no monitoring data in the lower left and lower left parts, and the axial force is displayed as 0); (2) from the top to the middle and then to the bottom, the bending moment changes from positive to negative, and then to positive, indicating that the water and soil pressure at the top and bottom is greater than the water and soil pressure at the side, and the segment presents a stress state of "compression up and down, expansion left and right". From the top to the middle to the bottom, the pressure is mainly on the outside, then on the inside, and then on the outside (there is no monitoring data in the lower left and lower left parts, and the axial force is displayed as 0); (3) The state presented by the segment is consistent with the small eccentric compression state considered in the design.

[0360] The trend of axial force and bending moment changing with time: The axial force and bending moment calculated by concrete strain at the upper right side (1 o'clock), the middle right side (4 o'clock) and the middle left side (13 o'clock) of the 3972 ring are shown as follows: (1) As time goes by, the axial force still has a trend of gradually increasing, but the increase is very small; (2) The bending moment gradually decreases and has stabilized, indicating that the water and soil loads along the pipe segment are gradually adjusted to a uniform distribution; (3) The increase in soil pressure due to rheological effects is uniform, which increases the axial force and reduces the bending moment, with a trend of changing from small eccentric compression to axial compression, which is beneficial to the bearing capacity of the pipe segment;

[0361] Bearing capacity envelope diagram based on concrete strain: The bearing capacity envelope diagram of axial force and bending moment of ring 3972 is calculated based on concrete strain. (1) The stress state of the ring 3972 segment is within the bearing capacity envelope range considering the combined effect of steel bars and concrete, and does not exceed the bearing capacity envelope range of plain concrete; (2) From January to April 2024, the axial force and bending moment at the same point changed very little, and the stress of the ring segment tended to be stable.

[0362] Bearing capacity envelope diagram based on water and soil pressure: The water and soil pressure monitored by the 3972 ring is used as the segment load to calculate the bearing capacity envelope diagram of axial force and bending moment. The trend of the envelope diagram is consistent with the bearing capacity trend obtained by concrete strain calculation, and the segment is within the design bearing capacity range.

[0363] Furthermore, the step of comparing the real-time monitored water and soil pressure of the segment to be evaluated with the design value to determine the safety of the design value of the segment to be evaluated further includes:

[0364] Design water and soil pressure values ​​and lateral pressure coefficient values ​​for lateral pressure tests;

[0365] Comparing the monitored water and soil pressure with the design value, the lateral earth pressure coefficient obtained by monitoring is greater than the design value, and the design value safety of the design load value is high.

[0366] Furthermore, the segment emergency reinforcement plan corresponding to the safety of the design value of the segment to be evaluated further includes:

[0367] During the construction process, if the monitoring data reaches the warning standard or the measured deformation value is greater than 2 / 3 of the allowable deformation, an alarm report should be sent;

[0368] When the tunnel structure shows deformation, cracks, water leakage, or the shield segment clearance convergence deformation rate is greater than 2mm / d, and the cumulative clearance convergence deformation value is greater than 10mm, the deep buried shield tunnel segment reinforcement treatment shall be carried out.

[0369] In this embodiment, during the segment structure design phase, according to Sections 5.2.3 and 5.2.6 of the "Standard for Design of Shield Tunnel Engineering" (GB-51438-2021), vertical stratum pressure should be factored into the soil unloading arch effect for deep-buried shield tunnels in clay strata with a SPF greater than 8, and external water pressure in clay strata should be determined using a combined water-soil method. The deep-buried section of the inverted siphon shield tunnel is located in the ①-7 stratum, a clay stratum with a SPF greater than 8. The design water-soil pressure values ​​for different deep-buried sections were obtained from Table 2. The water-soil loads were calculated and analyzed using a combined water-soil method, taking into account the soil unloading arch effect at the tunnel top, using the Terzaghi formula.

[0370] The section with pile number LQS4+868.4 is selected as the typical section for deep buried structure design. The buried depth of this section is 73.9m, and the distance from the groundwater surface to the top of the tunnel is 60.5m.

[0371] Table 2 Design water and soil pressure values ​​for deep buried section

[0372]

[0373] In this example, "Water and Soil Pressure Testing and Key Parameter Research in Deep Composite Soft Soil Layers," key physical and mechanical parameters of deep composite soft soil layers were proposed through a combination of indoor and in-situ testing. The recommended static lateral pressure coefficient for the fine sand layer in soil layer ①-1 is 0.31, and its recommended lateral subgrade coefficient is 43 MPa / m. The recommended static lateral pressure coefficient for the clay layer ①-7 is 0.48, and its recommended lateral subgrade coefficient is 49 MPa / m.

[0374] The 4160, 4047 and 3972 rings monitored in this embodiment are all deep-buried tunnel sections. The comparison results of the water-soil pressures and the designed water-soil pressures of the three sections obtained by monitoring are shown in Table 3. The lateral pressure coefficient is the ratio of the average lateral pressure (the average of the lateral top, lateral middle and lateral bottom) to the average value of the top and bottom pressures (the average of the top pressure and the bottom pressure). It can be seen that (1) the design value of the top pressure of the deep-buried tunnel section is relatively close to the monitored value; (2) it is assumed that the top pressure and the bottom pressure are close during design, and only the soil pressure difference caused by the cavern height is considered, but the monitoring results show that the top soil pressure and the bottom soil pressure differ greatly; (3) the monitored lateral pressure coefficient is greater than the designed lateral pressure coefficient; it is safe to use a lateral pressure coefficient of about 0.5.

[0375] Table 3 Comparison of designed water and soil pressure values ​​and monitored values ​​in deep buried section

[0376]

[0377] According to a second embodiment of the present invention, the present invention claims protection for a shield tunnel segment safety assessment system based on data monitoring, comprising:

[0378] one or more processors;

[0379] A memory having one or more programs stored thereon, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the shield tunnel segment safety evaluation method based on data monitoring.

[0380] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0381] In addition, the functional units in the various embodiments of the present application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units. The above is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

[0382] The above detailed description of the specific embodiments of the invention is intended only as an example, and the present application is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications or substitutions of the invention are also within the scope of the present application. Therefore, equivalent changes, modifications, and improvements made without departing from the spirit and scope of the present application should be included within the scope of the present application.

Claims

1. A shield tunnel segment safety evaluation method based on data monitoring, characterized in that: include: Select monitoring indicators of the segment to be evaluated, and calculate the first bending moment and first axial force of the segment to be evaluated based on water and soil pressure load monitoring indicators, including tangential load and radial load acting on the micro-segment of the lining; Calculating the second bending moment and the second axial force of the segment to be evaluated based on the concrete strain and the steel bar stress; When calculating the second bending moment and the second axial force, the thin shell method is used to calculate the internal force of the shield segment as a bearing capacity monitoring indicator. For sections where both steel bar gauges and concrete strain gauges are laid out, the eccentric short column method is used to verify the axial force and bending moment. In the eccentric short column method, the tunnel lining is considered as an eccentrically compressed short column, taking into account the role of reinforcement; The stress-strain relationship of the steel bar is linear; The stress-strain relationship of concrete is linear or nonlinear; The calculation formula is: ； Where: N - axial force KN; M - bending moment KN m; A - cross-sectional area of ​​the component m 2 ; h - the height of the component in m; b - width of the component in m; A' S1 、A' S2 ——area of ​​steel bars at both ends respectively (m) 2 ; σ c1 , σ c2 ——Respectively the concrete compressive stress at both ends KN / m 2 ; σ s1 , σ s2 ——Respectively the compressive stress of the steel bars at both ends KN / m 2 ; n1, n2 - the number of inner and outer steel bars; p1, p2 - concentrated force of inner and outer steel bars KN; α, α′ – the distance from the steel bar resultant point to the edge in m; Reinforcement is ignored in the thin shell method; The stress-strain relationships of both steel and concrete are linear; According to different axial compression states, eccentric compression states, and eccentric tension states, the steel bars and concrete jointly bear the bending moment and axial force of the section, and based on the axial force balance and bending moment balance equations, the cross-sectional steel reinforcement beam index of the segment to be evaluated is forward calculated to solve the segment bearing capacity envelope diagram; When analyzing the time-history trend of the section of the segment to be evaluated based on the segment bearing capacity, obtaining water and soil pressure monitoring data and concrete strain monitoring data of the section of the segment to be evaluated; Analyzing the water and soil pressure monitoring data and the concrete strain monitoring data to obtain a time history trend of the cross section of the segment to be evaluated; The water and soil pressure monitoring data includes at least: water and soil pressure during the construction phase and long-term water and soil pressure; The concrete strain monitoring data includes at least: the compressive state of the pipe segment section; The relationship between the outer and inner compressive stresses at various locations on the segment; Trend of ring concrete compressive strain over time; Design water and soil pressure values ​​and lateral pressure coefficient values ​​for lateral pressure tests; Comparing the monitored water and soil pressure with the design value, the lateral earth pressure coefficient obtained by monitoring is greater than the design value, and the design load value has a high safety; A corresponding segment emergency reinforcement plan is configured based on the safety of the design values ​​of the segment to be evaluated.

2. A shield tunnel segment safety evaluation method based on data monitoring according to claim 1, characterized in that: Select monitoring indicators for the segments to be evaluated, including: Water and soil pressure load monitoring indicators; Internal force monitoring indicators of reinforced concrete components; Segment deformation monitoring indicators; The water and soil pressure load monitoring indicator adopts the segment forward design method, uses the monitored water and soil pressure as the load borne by the segment, calculates the axial force and bending moment borne by different sections of the segment to be evaluated, and draws a bearing capacity envelope diagram based on the actual reinforced concrete parameters of the segment to be evaluated; The internal force monitoring indicators of reinforced concrete components include lining internal force, which is calculated by arranging steel bar gauges and concrete strain gauges on the inner and outer sides of the segment to be evaluated, and back-calculating axial force and bending moment based on the monitoring values; The segment deformation monitoring indicators are obtained by monitoring the segment deformation and settlement using a total station. No permanent deformation monitoring equipment and collection devices are set up. When the segment internal force monitoring value is abnormal, the segment deformation and settlement are measured more frequently.

3. A shield tunnel segment safety evaluation method based on data monitoring according to claim 2, characterized in that: Analyzing the time history trend and operational health status of the section of the segment to be evaluated based on the segment bearing capacity also includes: When analyzing the operational health status of the section of the segment to be evaluated based on the segment bearing capacity, obtaining an axial force and bending moment distribution diagram, a time-varying trend diagram of the axial force and bending moment, a bearing capacity envelope diagram based on concrete strain, and a bearing capacity envelope diagram based on water and soil pressure of the section of the segment to be evaluated; The operational health status of the section of the pipe segment to be evaluated is obtained by analyzing the axial force and bending moment distribution diagram of the section of the pipe segment to be evaluated, the axial force and bending moment change trend diagram over time, the bearing capacity envelope diagram based on concrete strain, and the bearing capacity envelope diagram based on water and soil pressure.

4. A shield tunnel segment safety evaluation method based on data monitoring according to claim 1, characterized in that: The segment emergency reinforcement plan corresponding to the design value safety configuration of the segment to be evaluated further includes: During the construction process, if the monitoring data reaches the warning standard or the measured deformation value is greater than 2 / 3 of the allowable deformation, an alarm report should be sent; When the tunnel structure shows deformation, cracks, water leakage, or the shield segment clearance convergence deformation rate is greater than 2mm / d, and the cumulative clearance convergence deformation value is greater than 10mm, the deep buried shield tunnel segment reinforcement treatment shall be carried out.

5. A shield tunnel segment safety evaluation system based on data monitoring, characterized in that: include: one or more processors; A memory having one or more programs stored thereon, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement a shield tunnel segment safety evaluation method based on data monitoring according to any one of claims 1 to 4.

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