Longitudinal dynamic floating prediction method for segment in shield tunnel construction period

Abstract

The invention provides a shield tunnel construction period segment longitudinal dynamic floating prediction method, and relates to the field of shield tunnel segment floating prediction.The method comprises the steps that the static upward floating force and the dynamic upward floating force of a shield tunnel are calculated by considering the timeliness of slurry, and the characteristic of nonlinear change of the rigidity of a circular seam connector is considered; the method comprises the following steps: dividing bending-resistant and shearing-resistant deformation modes of a circular seam joint, further deducing bending rigidity and shearing rigidity of a tenon-type joint in each deformation stage, deducing a shield tail segment longitudinal floating prediction model of the circular seam joint in the shield tunnel construction period, and constructing a nonlinear iterative algorithm of shield tunnel longitudinal deformation according to the theories; and acquiring parameter data of actual engineering, and inputting the parameter data into the duct piece floating prediction model to obtain a duct piece floating value. By means of the method, accurate prediction of floating deformation of the shield tail segment in large shield tunneling can be achieved, an effective scientific basis is provided for large-diameter shield tunneling construction, the problems that parameter decision of shield tunneling machine operators is difficult, and the segment floating control effect is poor are solved, and structural diseases caused by too large floating of the shield tail segment are eliminated.

Description

Technical Field

[0001] The present invention relates to the field of shield tunnel uplift prediction, and in particular to a method for predicting the longitudinal dynamic uplift of a segment during the construction period of a shield tunnel. Background Art

[0002] The shield method has been widely used in my country due to its advantages of high construction efficiency, safety, and low environmental impact. With the continuous construction of shield tunnel projects, shield construction technology is gradually developing towards large diameter, long distance, large burial depth, high water pressure and intelligence, and the stratum conditions traversed by shield tunnels are becoming more and more complex. In a complex geological environment with high water pressure, how to ensure the safety performance of shield tunnels during the construction and operation periods has become an important proposition. According to statistics, by the end of 2024, the total number of large-diameter shield tunnels (diameter 10m to 14m) built in my country has exceeded 2 / 3 of the world's total, making it the country with the largest number of large-diameter shield tunnels in the world.

[0003] During shield tunnel construction, because the diameter of the shield machine's outer casing is larger than the outer diameter of the segments, a circular over-excavation gap, known as the shield tail gap, forms between the segments and the soil as the shield machine advances, temporarily leaving the soil surrounding the tunnel hollow. To eliminate this phenomenon, grouting pipes are often pre-buried at the shield tail, and the shield tail gap is filled through simultaneous grouting. However, since the grouting slurry remains in a fluid state for a long time after being injected into the shield tail gap, the buoyancy of the slurry and the grouting pressure can cause the segments to float upward, leading to safety accidents such as tunnel axis deviation, misalignment or damage between segment rings, and water seepage and leakage within the tunnel. These accidents can damage ground buildings and pose safety risks to the subway during later operations. Therefore, studying the issue of segment floating during shield tunnel construction is extremely important. Furthermore, compared to other tunnel types like immersed tubes and jacking tunnels, shield tunnel linings are constructed from precast reinforced concrete segments connected by bolts. The presence of tunnel joints renders the lining structure discontinuous. Joints are both a crucial component and the weakest link in shield tunnel construction, their mechanical properties influencing and even controlling the overall response of the lining. Among structural defects caused by the longitudinal uplift of segments during shield tunnel construction, damage often occurs at circumferential joints. Therefore, the influence of circumferential joints on the overall longitudinal deformation of shield tunnels cannot be ignored.

[0004] Although my country has accumulated extensive experience in shield construction, large-diameter shield tunnel construction is still in its early stages, and theoretical research on construction-period flotation remains insufficient. Therefore, this invention, considering the effects of slurry aging and tunnel circumferential joints on the longitudinal flotation of segments, proposes a more reasonable shield tunnel flotation prediction model. This further explains the longitudinal deformation patterns and characteristics of segments during shield construction, which is crucial for the subsequent development of large-diameter shield tunnel projects. Summary of the Invention

[0005] Based on the above analysis, the present invention provides a method for predicting the longitudinal dynamic uplift of tunnel segments during the construction period of a shield tunnel, so as to overcome the shortcomings of the existing technology and achieve accurate prediction of the uplift amount of tunnel segments during the construction period.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: A method for predicting the longitudinal dynamic uplift of a segment during shield tunnel construction, comprising:

[0007] Step 1: Establish a longitudinal uplift prediction model for the shield tail segment that takes into account the slurry hardening process, static and dynamic uplift forces, nonlinear changes in the formation resistance coefficient, and the accumulation of construction steps;

[0008] Step 2: Considering the nonlinear variation characteristics of the girth joint stiffness, the bending and shear deformation modes of the girth joint are divided, and the bending stiffness and shear stiffness of the tenon joint at each deformation stage are further derived;

[0009] Step 3: Consider the tunnel as a Timoshenko beam-spring model placed on a Winkler elastic foundation. Based on the force and moment balance of the ring segment, the governing differential equation for the bending displacement wb of the tunnel ring segment under the action of longitudinal external loads, taking into account the axial force, can be obtained. The shield tunnel is then discretized, and the displacement differential equation is solved using the finite difference method.

[0010] Step 4: Construct an iterative algorithm for the nonlinear longitudinal deformation of the shield tunnel. An iterative algorithm for joint stiffness is used. The bending moment and vertical displacement of the inter-ring joints are used as basic variables. The calculation formulas for the bending stiffness and shear stiffness of the tunnel joints are continuously adjusted to achieve nonlinear changes in the joint stiffness and calculate the buoyancy of the segments accordingly.

[0011] Step 5: Obtain parameter data of the actual project, input the parameter data into the segment floating prediction model, and predict the segment floating value.

[0012] Furthermore, the adjustment of the nonlinear change of the joint stiffness includes:

[0013] Taking the inter-ring joint bending moment and vertical displacement as the basic variables, the inter-ring joint bending moment is compared with the critical values of the three modes of joint bending deformation; the inter-ring stagger amount is compared with the assembly gap of the annular joint components, and the calculation formulas of the tunnel joint bending stiffness and shear stiffness are continuously adjusted.

[0014] Furthermore, the longitudinal buoyancy of the shield tunnel considering the slurry aging is calculated as:

[0015]

[0016] Calculate the static buoyancy: where L is the distance from any cross-section along the longitudinal direction of the tunnel to the shield tail, ve is the tunneling speed of the shield machine, am is the fitting coefficient, and γg is the density of the synchronous grouting slurry.

[0017]

[0018] Calculate the dynamic buoyancy, where t is the longitudinal filling time of the slurry along the tunnel, τ0 is the initial shear stress, μ0 is the initial viscosity, a is the time-varying coefficient, ve is the tunneling speed of the shield machine, and p0 is the grouting pressure on the segment at the end of the circumferential filling.

[0019] Furthermore, the longitudinal uplift prediction model of the shield tail segment, which takes into account the slurry hardening process, static and dynamic uplift forces, nonlinear changes in the formation resistance coefficient, and the accumulation of construction steps, is:

[0020] The model is divided into three parts along the longitudinal direction. The L1 section is the shield tail section where the segment is still inside the shield shell. It is constrained by the shield tail brush and jack shoe. The length of this section is about 2 rings of segment width. The L2 section is the unsolidified section where the segment floats up significantly during the whole process from the start of synchronous grouting to the solidification of the slurry. The length of this stage is affected by the shield tunneling speed.

[0021] Ve is controlled by the solidification time of the grouting slurry, and its length can be calculated by the formula; the L3 section is the stable section after the slurry solidifies. In order to ensure that the stress conditions of the subsequent tunnel segments have enough time to change, the length of this section is 50m.

[0022]

[0023] Where k3 is the equivalent formation resistance coefficient of the stable section, Er is the equivalent formation deformation modulus of the stable section, υ is the Poisson's ratio, and Rc is the centroid radius of the segment.

[0024] k2=k3(1-e -bt )

[0025] Where k2 is the equivalent formation resistance coefficient of the unsolidified section, b is the time-varying coefficient, and t is the slurry setting time.

[0026] Furthermore, the bending and shear resistance modes of the annular seam joint are:

[0027] Based on the contact state of the annular joint and the position of the neutral axis, the bending deformation at the annular joint of a shield tunnel under the coupling of axial force and bending moment is divided into three deformation modes. The shear deformation is also divided into three deformation modes according to the different stages in which the shear force at the annular joint is shared by the sliding friction resistance of adjacent contact surfaces, the longitudinal bolts, and the tenon and groove.

[0028] Furthermore, the longitudinal uplift prediction model of the girth joint shield tunnel during construction is:

[0029] According to the force balance and bending moment balance of the ring segment, the governing differential equation for the bending displacement ωb of the tunnel ring segment under the action of longitudinal external load considering the axial force can be obtained:

[0030]

[0031] Where k is the foundation reaction coefficient, N is the axial force acting on the shield tunnel, q(z) is the additional load acting on the tunnel, z is the coordinate along the longitudinal direction of the tunnel, κGA is the shear stiffness of the beam, ωb is the bending displacement of the cross section, EI is the bending stiffness of the beam, and D is the outer diameter of the segment.

[0032] Furthermore, the shield tunnel is discretized and the displacement differential equation is solved using the finite difference method as follows:

[0033] ω b =[K b +K s -K t ] -1 q

[0034] Where Kb is the bending stiffness matrix of the girth joint, Ks is the shear stiffness matrix of the girth joint, Kt is the foundation stiffness matrix, q is the additional load vector acting on the tunnel, and ωb is the bending displacement of the cross section, that is, the uplift of the shield tunnel.

[0035] Furthermore, the iterative algorithm for constructing the nonlinearity of longitudinal deformation of the shield tunnel is:

[0036] (1) Based on the initial load condition q(z) and the bending stiffness kb and shear stiffness ks of the tunnel joint in the first stage, the bending moment M and relative vertical displacement ωb of each inter-ring joint are obtained to generate the initial joint stiffness.

[0037] (2) Solve the model for the first time, input the initial bending stiffness and shear stiffness of the tunnel joint, and obtain the bending moment M and relative vertical displacement w of the tunnel at the i nodes in the calculation model.

[0038] (3) Update the bending stiffness and shear stiffness of the joint node based on the calculated internal forces and displacements.

[0039] (4) The tunnel displacement control equation is solved again using the updated bending stiffness and shear stiffness of each joint to obtain the bending moment M and relative vertical displacement w of the i-th node of the shield tunnel.

[0040] The beneficial effects of this invention are: Based on the consideration of the superposition effect of shield construction steps and the law of slurry buoyancy dissipation, it further comprehensively considers the time-varying rheological properties and deformation modulus of the synchronous grouting slurry, as well as the nonlinear deformation characteristics of bending and shear of the tenon-type annular joints, thereby establishing a more accurate segment uplift prediction model during the construction of large-diameter shield tunnels. This provides an effective scientific basis for large-diameter shield tunneling construction, solves the problems of difficult parameter decision-making for shield machine operators and poor segment uplift control, and eliminates structural defects caused by excessive uplift of the shield tail segment. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A flowchart of a method for predicting the longitudinal dynamic uplift of segments during shield tunnel construction provided by an embodiment of the present invention;

[0042] Figure 2 This is a flow chart of a system for predicting the longitudinal dynamic uplift of segments during shield tunnel construction provided by an embodiment of the present invention;

[0043] Figure 3 This is a comparison chart of the calculation results of the shield tunnel segment longitudinal dynamic uplift prediction system during construction provided by an embodiment of the present invention and the calculation results of other methods. DETAILED DESCRIPTION

[0044] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0045] like Figure 1 As shown, an embodiment of the present invention provides a method for predicting the longitudinal dynamic floating of a segment during shield tunnel construction, comprising the following steps:

[0046] Step 1: Establish a longitudinal uplift prediction model for the shield tail segment that takes into account the slurry hardening process, static and dynamic uplift forces, nonlinear changes in the formation resistance coefficient, and the accumulation of construction steps;

[0047] Step 2: Considering the nonlinear variation characteristics of the girth joint stiffness, the bending and shear deformation modes of the girth joint are divided, and the bending stiffness and shear stiffness of the tenon joint at each deformation stage are further derived;

[0048] Step 3: Consider the tunnel as a Timoshenko beam-spring model placed on a Winkler elastic foundation. Based on the force and moment balance of the ring segment, the governing differential equation for the bending displacement wb of the tunnel ring segment under the action of longitudinal external loads, taking into account the axial force, can be obtained. The shield tunnel is then discretized, and the displacement differential equation is solved using the finite difference method.

[0049] Step 4: Construct an iterative algorithm for the nonlinear longitudinal deformation of the shield tunnel. An iterative algorithm for joint stiffness is used. The bending moment and vertical displacement of the inter-ring joints are used as basic variables. The calculation formulas for the bending stiffness and shear stiffness of the tunnel joints are continuously adjusted to achieve nonlinear changes in the joint stiffness and calculate the buoyancy of the segments accordingly.

[0050] Step 5: Obtain parameter data of the actual project, input the parameter data into the segment floating prediction model, and predict the segment floating value.

[0051] It should be understood that the buoyancy of the segments refers to the fact that after the construction of the shield machine is completed, the assembled segments will be formed. When the assembled segments are in direct contact with the soil, the buoyancy of the segments is greater than the gravity of the segments themselves, thereby causing the segments to move upward; the joint stiffness refers to the stiffness characteristics of the tunnel segments at the annular joints, which reflects the ability of the annular joints of the segments to deform under the action of force and external pressure.

[0052] Optionally, adjusting for nonlinear changes in joint stiffness includes:

[0053] Taking the inter-ring joint bending moment and vertical displacement as the basic variables, the inter-ring joint bending moment is compared with the critical values of the three modes of joint bending deformation; the inter-ring stagger amount is compared with the assembly gap of the annular joint components, and the calculation formulas of the tunnel joint bending stiffness and shear stiffness are continuously adjusted.

[0054] It is explained that the bending moment of the joint between the rings is compared with the critical values of the three modes of the joint bending deformation; the misalignment between the rings is compared with the assembly gap of the annular joint components, and the actual engineering data parameters can be input into the floating prediction system of the present invention for calculation.

[0055] Optionally, the longitudinal buoyancy of the shield tunnel considering the slurry aging is calculated as:

[0056]

[0057] Calculate the static buoyancy: where L is the distance from any cross-section along the longitudinal direction of the tunnel to the shield tail, ve is the tunneling speed of the shield machine, am is the fitting coefficient, and γg is the density of the synchronous grouting slurry.

[0058]

[0059] Calculate the dynamic buoyancy, where t is the longitudinal filling time of the slurry along the tunnel, τ0 is the initial shear stress, μ0 is the initial viscosity, a is the time-varying coefficient, ve is the tunneling speed of the shield machine, and p0 is the grouting pressure on the segment at the end of the circumferential filling.

[0060] To clarify, static buoyancy refers to the force generated by the grouting slurry wrapping the pipe segments, and dynamic buoyancy refers to the force caused by the grouting pressure during synchronous grouting.

[0061] Optionally, the longitudinal uplift prediction model of the shield tail segment taking into account the slurry hardening process, static and dynamic uplift forces, nonlinear changes in the formation resistance coefficient, and the accumulation of construction steps is:

[0062] The model is divided into three parts along the longitudinal direction. The L1 section is the shield tail section where the segment is still inside the shield shell. It is constrained by the shield tail brush and jack shoe. The length of this section is about 2 rings of segment width. The L2 section is the unsolidified section where the segment floats up significantly during the whole process from the start of synchronous grouting to the solidification of the slurry. The length of this stage is affected by the shield tunneling speed.

[0063] Ve is controlled by the solidification time of the grouting slurry, and its length can be calculated by the formula; the L3 section is the stable section after the slurry solidifies. In order to ensure that the stress conditions of the subsequent tunnel segments have enough time to change, the length of this section is 50m.

[0064]

[0065] Where k3 is the equivalent formation resistance coefficient of the stable section, Er is the equivalent formation deformation modulus of the stable section, υ is the Poisson's ratio, and Rc is the centroid radius of the segment.

[0066] k2=k3(1-e -bt )

[0067] Where k2 is the equivalent formation resistance coefficient of the unsolidified section, b is the time-varying coefficient, and t is the slurry setting time.

[0068] It can be explained that the ground resistance coefficient is an important parameter used to describe the ability of soil or foundation materials to respond to structural settlement and lateral deformation. It is often used to analyze and design the stability and service performance of tunnel structures.

[0069] Specifically, in order to more realistically simulate the actual working conditions on site, slurry material performance tests were carried out. According to the grouting material performance tests, it was found that the change in the tunnel synchronous grouting slurry performance over time was approximately an exponential function growth, and the time-varying coefficient of the key parameter in the relationship between the equivalent formation resistance coefficient of the solidified section and the unsolidified section was obtained. This embodiment is based on the Jinan Yellow River Tunnel Project, and the time-varying coefficient is b = -0.439.

[0070] Optionally, the bending and shear resistance modes of the annular seam joint are:

[0071] Based on the contact state of the annular joint and the position of the neutral axis, the bending deformation at the annular joint of a shield tunnel under the coupling of axial force and bending moment is divided into three deformation modes. The shear deformation is also divided into three deformation modes according to the different stages in which the shear force at the annular joint is shared by the sliding friction resistance of adjacent contact surfaces, the longitudinal bolts, and the tenon and groove.

[0072] Optionally, the longitudinal uplift prediction model of the girth joint shield tunnel during construction is:

[0073] According to the force balance and bending moment balance of the ring segment, the governing differential equation for the bending displacement ωb of the tunnel ring segment under the action of longitudinal external load considering the axial force can be obtained:

[0074]

[0075] Where k is the foundation reaction coefficient, N is the axial force acting on the shield tunnel, q(z) is the additional load acting on the tunnel, z is the coordinate along the longitudinal direction of the tunnel, κGA is the shear stiffness of the beam, ωb is the bending displacement of the cross section, EI is the bending stiffness of the beam, and D is the outer diameter of the segment.

[0076] Optionally, the shield tunnel is discretized and the displacement differential equation is solved using the finite difference method as follows:

[0077] ω b =[K b +K s -K t ] -1 q

[0078] Where Kb is the bending stiffness matrix of the girth joint, Ks is the shear stiffness matrix of the girth joint, Kt is the foundation stiffness matrix, q is the additional load vector acting on the tunnel, and ωb is the bending displacement of the cross section, that is, the uplift of the shield tunnel.

[0079] like Figure 2 As shown, an embodiment of the present invention provides a system for predicting the rise of segments during shield tunnel construction:

[0080] (1) Based on the initial load condition q(z) and the bending stiffness kb and shear stiffness ks of the tunnel joint in the first stage, the bending moment M and relative vertical displacement ωb of each inter-ring joint are obtained to generate the initial joint stiffness.

[0081] (2) Solve the model for the first time, input the initial bending stiffness and shear stiffness of the tunnel joint, and obtain the bending moment M and relative vertical displacement w of the tunnel at the i nodes in the calculation model.

[0082] (3) Update the bending stiffness and shear stiffness of the joint node based on the calculated internal forces and displacements.

[0083] (4) The tunnel displacement control equation is solved again using the updated bending stiffness and shear stiffness of each joint to obtain the bending moment M and relative vertical displacement w of the i-th node of the shield tunnel.

[0084] Combine Figure 1 and Figure 3In order to ensure the accuracy of the method for predicting the longitudinal dynamic buoyancy of the segments during shield tunnel construction, this embodiment is based on the Jinan Chuanhuang Tunnel project. The static and dynamic buoyancy forces on the segments separated from the first ring of the shield tail are calculated to be 3592.41kN / m and 428.75kN / m respectively, and the anti-buoyancy force generated by the segment's own weight is 769.3kN / m. The actual engineering data parameters are substituted into the tunnel longitudinal buoyancy calculation model, and the buoyancy of the segments under a single construction step load is accumulated and summed to obtain the theoretical solution for the cumulative buoyancy of the tunnel. The comparison results with the actual measurements are shown in the figure below. Figure 3 As shown in the figure, the longitudinal variation patterns of the theoretical calculation results are consistent with the field measurements, confirming the correctness of the calculation theory proposed in this patent. It also proves that the floatation prediction model proposed in this patent can accurately predict the longitudinal dynamic floatation of the tail segment during the construction of large-diameter shield tunnels with distributed concave and convex tenons.

Claims

1. A method for predicting the longitudinal dynamic uplift of a segment during shield tunnel construction, characterized in that: The method comprises: Step 1: Establish a longitudinal uplift prediction model for the shield tail segment that takes into account the slurry hardening process, static and dynamic uplift forces, nonlinear changes in the formation resistance coefficient, and the accumulation of construction steps; Step 2: Considering the nonlinear variation characteristics of the girth joint stiffness, the bending and shear deformation modes of the girth joint are divided, and the bending stiffness and shear stiffness of the tenon joint at each deformation stage are further derived; Step 3: Consider the tunnel as a Timoshenko beam-spring model placed on a Winkler elastic foundation. Based on the force and moment balance of the ring segment, the governing differential equation for the bending displacement wb of the tunnel ring segment under the action of longitudinal external loads, taking into account the axial force, can be obtained. The shield tunnel is then discretized, and the displacement differential equation is solved using the finite difference method. Step 4: Construct an iterative algorithm for the nonlinear longitudinal deformation of the shield tunnel. An iterative algorithm for joint stiffness is used. The bending moment and vertical displacement of the inter-ring joints are used as basic variables. The calculation formulas for the bending stiffness and shear stiffness of the tunnel joints are continuously adjusted to achieve nonlinear changes in the joint stiffness and calculate the buoyancy of the segments accordingly. Step 5: Obtain parameter data of the actual project, input the parameter data into the segment floating prediction model, and predict the segment floating value.

2. A method for predicting the longitudinal dynamic uplift of a segment during shield tunnel construction as claimed in claim 1, characterized in that: Adjustments for nonlinear changes in joint stiffness include: Taking the inter-ring joint bending moment and vertical displacement as the basic variables, the inter-ring joint bending moment is compared with the critical values of the three modes of joint bending deformation; the inter-ring stagger amount is compared with the assembly gap of the annular joint components, and the calculation formulas of the tunnel joint bending stiffness and shear stiffness are continuously adjusted.

3. A method for predicting the longitudinal dynamic uplift of a segment during shield tunnel construction as claimed in claim 2, characterized in that: The longitudinal buoyancy of the shield tunnel considering the slurry aging is calculated as follows: Calculate the static buoyancy: where L is the distance from any cross-section along the longitudinal direction of the tunnel to the shield tail, ve is the tunneling speed of the shield machine, am is the fitting coefficient, and γg is the density of the synchronous grouting slurry. Calculate the dynamic buoyancy, where t is the longitudinal filling time of the slurry along the tunnel, τ0 is the initial shear stress, μ0 is the initial viscosity, a is the time-varying coefficient, ve is the tunneling speed of the shield machine, and p0 is the grouting pressure on the segment at the end of the circumferential filling.

4. A method for predicting the longitudinal dynamic uplift of a segment during shield tunnel construction as claimed in claim 3, characterized in that: The longitudinal uplift prediction model of the shield tail segment, which takes into account the slurry hardening process, static and dynamic uplift forces, nonlinear changes in the formation resistance coefficient, and the accumulation of construction steps, is: The model is divided into three parts along the longitudinal direction. The L1 section is the shield tail section where the segment is still inside the shield shell. It is constrained by the shield tail brush and jack shoe. The length of this section is about 2 rings of segment width. The L2 section is the unsolidified section where the segment floats up significantly during the whole process from the start of synchronous grouting to the solidification of the slurry. The length of this stage is affected by the shield tunneling speed. Ve is controlled by the solidification time of the grouting slurry, and its length can be calculated by the formula; the L3 section is the stable section after the slurry solidifies. In order to ensure that the stress conditions of the subsequent tunnel segments have enough time to change, the length of this section is 50m. Where k3 is the equivalent formation resistance coefficient of the stable section, Er is the equivalent formation deformation modulus of the stable section, υ is the Poisson's ratio, and Rc is the centroid radius of the segment. k2=k3(1-e -bt ) Where k2 is the equivalent formation resistance coefficient of the unsolidified section, b is the time-varying coefficient, and t is the slurry setting time.

5. A method for predicting the longitudinal dynamic uplift of a segment during shield tunnel construction as claimed in claim 4, characterized in that: The bending and shear resistance modes of the annular seam joint are: Based on the contact state of the annular joint and the position of the neutral axis, the bending deformation at the annular joint of a shield tunnel under the coupling of axial force and bending moment is divided into three deformation modes. The shear deformation is also divided into three deformation modes according to the different stages in which the shear force at the annular joint is shared by the sliding friction resistance of adjacent contact surfaces, the longitudinal bolts, and the tenon and groove.

6. A method for predicting the longitudinal dynamic uplift of a segment during shield tunnel construction as claimed in claim 5, characterized in that: The longitudinal uplift prediction model of the annular joint shield tunnel during construction is: According to the force balance and bending moment balance of the ring segment, the governing differential equation for the bending displacement ωb of the tunnel ring segment under the action of longitudinal external load considering the axial force can be obtained: Where k is the foundation reaction coefficient, N is the axial force acting on the shield tunnel, q(z) is the additional load acting on the tunnel, z is the coordinate along the longitudinal direction of the tunnel, κGA is the shear stiffness of the beam, ωb is the bending displacement of the cross section, EI is the bending stiffness of the beam, and D is the outer diameter of the segment.

7. A method for predicting the longitudinal dynamic uplift of a segment during shield tunnel construction as claimed in claim 6, characterized in that: The shield tunnel is discretized and the displacement differential equation is solved using the finite difference method as follows: ω b =[K b +K s -K t ] -1 q Where Kb is the bending stiffness matrix of the girth joint, Ks is the shear stiffness matrix of the girth joint, Kt is the foundation stiffness matrix, q is the additional load vector acting on the tunnel, and ωb is the bending displacement of the cross section, that is, the uplift of the shield tunnel.

8. A method for predicting the longitudinal dynamic uplift of a segment during shield tunnel construction as claimed in claim 7, characterized in that: The iterative algorithm for constructing the nonlinearity of longitudinal deformation of shield tunnel is: (1) Based on the initial load condition q(z) and the bending stiffness kb and shear stiffness ks of the tunnel joint in the first stage, the bending moment M and relative vertical displacement ωb of each inter-ring joint are obtained to generate the initial joint stiffness. (2) Solve the model for the first time, input the initial bending stiffness and shear stiffness of the tunnel joint, and obtain the bending moment M and relative vertical displacement w of the tunnel at the i nodes in the calculation model. (3) Update the bending stiffness and shear stiffness of the joint node based on the calculated internal forces and displacements. (4) The tunnel displacement control equation is solved again using the updated bending stiffness and shear stiffness of each joint to obtain the bending moment M and relative vertical displacement w of the i-th node of the shield tunnel.

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