Tunnel supporting structure and tunnel supporting structure parameter optimization method
By installing steel support structures made of steel mesh, anchor bolts, and "U"-shaped steel plates inside the tunnel, and optimizing parameters using a finite element numerical calculation model, the problems of high project cost and difficulty in ensuring construction quality during tunnel construction were solved, achieving stable support and ease of construction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-26
- Publication Date
- 2026-03-10
AI Technical Summary
In existing tunnel construction, the tunnel lining structures using open-type TBMs and shield-type TBMs have problems such as difficulty in ensuring construction quality, high project costs, and large steel consumption.
A steel support structure made of steel mesh, anchor bolts, and "U"-shaped steel plates is used. The structural parameters are optimized by combining a finite element numerical calculation model to form a spiral tunnel support structure, which is fixed to the inner wall of the tunnel by anchor bolts.
To reduce project costs, improve the working environment inside the tunnel, enhance construction convenience, and ensure stable tunnel support.
Smart Images
Figure CN121630482A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of tunnel support, and particularly relates to a tunnel support structure and a tunnel support structure parameter optimization method. BACKGROUND
[0002] Full-face tunnel boring machine (TBM) has been widely used in tunnel construction, which includes open TBM and shield TBM. When the open TBM is used for tunnel construction, the lining structure type in the tunnel adopts a composite lining structure of "primary support + secondary lining". The "primary support" is formed by a steel frame + sprayed concrete, and the steel frame is built by I-beams. The "secondary lining" is formed by cast-in-situ concrete. The above scheme has the following technical problems: firstly, the sprayed concrete has a great influence on the environment in the hole, and the construction quality is difficult to guarantee; secondly, the combined thickness of "primary support + secondary lining" is large, which leads to the increase of TBM excavation area and high engineering cost; thirdly, the steel frame built by I-beams has the problem of large steel consumption. When the shield TBM is used for tunnel construction, the lining structure type in the tunnel adopts a single-layer prefabricated segment assembly. The unit volume segment cost is about 2-3 times the cast-in-situ concrete cost, which has the problem of high cost. SUMMARY
[0003] The application solves the technical problem of providing a tunnel support structure and a tunnel support structure parameter optimization method, which can reduce the engineering cost while ensuring the stable support of the tunnel.
[0004] The technical scheme adopted by the application to solve the technical problem is: a tunnel support structure, comprising a steel mesh, an anchor rod structure, and a steel support structure made of a "several" shaped steel plate; the steel support structure is arranged on the inner wall of the tunnel in a spiral structure with the tunnel axis as the center and has a pitch; the steel support structure and the inner wall of the tunnel are provided with a steel mesh; the steel support structure comprises an arched web with an opening facing the inner wall of the tunnel, and wing plates arranged on both sides of the opening of the arched web; the wing plates and the steel mesh are fixed to the inner wall of the tunnel through the anchor rod structure.
[0005] Further, the anchor rod structure comprises a plurality of anchor rod units arranged at a distance from each other along the spiral extension direction of the steel support structure, the anchor rod unit comprises two anchor rods, one of the wing plates of the steel support structure and the steel mesh are fixed to the inner wall of the tunnel through one of the anchor rods, and the other wing plate of the steel support structure and the steel mesh are fixed to the inner wall of the tunnel through the other anchor rod.
[0006] Further, the anchor rod is a locking foot anchor rod.
[0007] The tunnel support structure parameter optimization method adopts the tunnel support structure, and comprises the following steps: S1, establish a finite element numerical calculation model based on the structure parameters of the tunnel excavation process and the construction process, the structure parameters including: steel plate thickness, arch height of the "J" shaped steel plate, width of the "J" shaped steel plate, arch web width, wing plate width, and pitch; S2, based on the finite element numerical calculation model, numerical simulation analysis is performed on the structure parameters; the finite element numerical calculation model is discretized into element nodes, and the element nodes are calculated through the balance equation, the geometric equation and the physical equation; (a) balance equation: ; ; ; wherein, σ x , σ y , σ z respectively, x, y, z normal stress component in the axial direction, τ xy , τ yz , τ zx respectively, x, y, z shear stress component in the axial direction, f x 、f y 、f z respectively, x, y, z volume force component in the axial direction; (b) geometric equation: ; ; ; wherein, ε x , ε y , ε z respectively, x, y, z normal strain component in the axial direction, γ xy , γ yz , γ zx respectively, x, y, z shear strain component in the axial direction, u, v, w respectively, x, y, z displacement component in the axial direction; (c) physical equation: ; ; ; Where E is the elastic modulus. Poisson's ratio; S3, calculate the structural safety factor K, compare the structural safety factor K with the value specified in the code to determine the optimal structural parameters; when the structural safety factor K is greater than the specified value, the corresponding combination of structural parameters is the optimal structural parameters; when the structural safety factor K is less than the specified value, adjust the structural parameters in S2 until the calculated structural safety factor K is greater than the specified value.
[0008] Furthermore, in the finite element numerical calculation model of step S1, the surrounding rock adopts an ideal elastic-plastic constitutive relation and the Drucker-Prager nonlinear yield criterion is selected for calculation and analysis. The yield criterion is as follows: ; ; ; in: I 1 It is the first invariant of stress; J 2 It is the second invariant of stress deviator; α This is an experimental constant related to the internal friction angle of rocks; K 1 These are experimental constants related to adhesive force; 1 represents the major principal stress; 2 represents the intermediate principal stress; 3 represents the minor principal stress.
[0009] Furthermore, in step S1, the finite element numerical calculation model for the spiral steel support structure adopts an ideal elastic model simulated by shell elements, and the constitutive relation is: ; in: For stress; In response to the situation; It is the elastic modulus.
[0010] Furthermore, for the calculation of the structural safety factor K in step S3, according to the stress state of the "ji"-shaped steel plate and concrete composite section, it is divided into the following situations: S301. When the neutral axis is located within the concrete area, the steel plate is completely in tension, and the basic calculation formula is: ; The calculation formula for the structural safety factor K deduced from the basic formula is: ; Where: α r is the reduction factor of the structure; R p is the design value of the tensile strength of the steel; A p is the cross-sectional area of the steel plate (per unit width); R w is the design value of the axial compressive strength of the concrete; b is the unit width of the steel plate; h is the thickness of the concrete above the steel plate; e is the eccentricity; S302. When the neutral axis is located within the "ji"-shaped steel plate area, part of the steel plate is in tension and part is in compression, and the basic calculation formula is: ; Where: f cd is the design value of the axial compressive strength of the concrete; A s is the cross-sectional area of the steel plate (per unit width); is the sub-area of the steel plate in the compression zone; f d is the design value of the tensile strength of the steel; is the design value of the compressive strength of the steel; B is the unit width of the steel plate; h c is the thickness of the concrete above the steel plate; e is the eccentricity; Y1 represents the distance from the resultant tensile stress in the tension zone of the steel plate to the resultant compressive stress in the concrete section of the compression zone; Y 2 represents the distance from the resultant tensile stress in the tension zone of the steel plate to the resultant compressive stress in the steel plate section; The structural safety factor K is solved using an iterative calculation method: S3021, in the first equation In the middle, let K=1, and find the cross-sectional area of the steel plate in the compression zone; S3022, Y1 and Y2 are calculated from the cross-sectional area of the steel plate in the compression zone; S3023, Substitute Y1 and Y2 into the second equation. The new K value is obtained from the middle; S3024, compare the new K value with the initial K value, and set the convergence rule to be that the difference between the two values is less than 1 × 10. -6 If the conditions are not met, the new K value is used to replace the initial K value and the calculation is repeated until the convergence condition is met; the K value at this time is the structural safety factor. S303, when the tension zone is located on the concrete side, first calculate the distance (eccentricity) from the point of application of the axial force to the centroid of the section. e 0: ; in: M For bending moment; N It is the axial force; when e 0 ≤0.20 h When the compressive strength controls the bearing capacity, the formula for calculating the structural safety factor K is: ; in: The longitudinal bending coefficient of the component; α is an experimental constant related to the internal friction angle of the rock; h The height of the cross section; b The width of the cross section; N It is the axial force; R a This refers to the ultimate compressive strength of concrete. when e 0 > 0.20 h When the tensile strength controls the bearing capacity, the formula for calculating the structural safety factor K is: ; in: The longitudinal bending coefficient of the component; h The height of the cross section; b The width of the cross section; R l The tensile ultimate strength of concrete; N This is the axial force.
[0011] Compared with existing technologies, the beneficial effects of this invention are: this invention provides a tunnel support structure and a method for optimizing tunnel support structure parameters, which reduces engineering costs while ensuring stable support for the tunnel. It also has advantages such as improving the working environment inside the tunnel and facilitating construction. Attached Figure Description
[0012] Figure 1 This is a three-dimensional schematic diagram of the tunnel support structure; Figure 2 This is a cross-sectional diagram of the tunnel support structure and the tunnel itself. Figure 3 This is a cross-sectional schematic diagram of the steel support structure; Figure 4 This is a flowchart of the method for optimizing tunnel support structure parameters; Figure label: 1-Reinforcing mesh; 2-Steel support structure; 201-Wing plate; 202-Web plate; 3-Anchor bolt. Detailed Implementation
[0013] The following is in conjunction with the appendix Figure 1 , 2 The invention is further illustrated in sections 3 and 4, as well as in the embodiments.
[0014] like Figure 1 , 2 As shown in Figure 3, the tunnel support structure includes a steel mesh 1, an anchor structure, and a steel support structure 2 made of "U"-shaped steel plates. The steel support structure 2 is spirally arranged on the inner wall of the tunnel with the tunnel axis as the center and has a pitch. The steel mesh 1 is arranged between the steel support structure 2 and the inner wall of the tunnel. The steel support structure 2 includes an arched web 202 with its opening facing the inner wall of the tunnel, and wing plates 201 arranged on both sides of the opening of the arched web 202. The wing plates 201 and the steel mesh 1 are fixed to the inner wall of the tunnel by the anchor structure.
[0015] Pitch refers to the distance between the arched webs 202 of two adjacent turns of the steel support structure 2 in the helical structure.
[0016] The arched web 202 and the flange 201 can be connected by welding. Preferably, the arched web 202 and the flange 201 are an integrally formed integral structure.
[0017] Preferably, the bolt structure includes a plurality of bolt units arranged at intervals along the spiral extension direction of the steel support structure 2. Each bolt unit includes two bolts 3. One flange 201 of the steel support structure 2 and the steel bar mesh 1 are fixed to the inner wall of the tunnel by one of the bolts 3, and the other flange 201 of the steel support structure 2 and the steel bar mesh 1 are fixed to the inner wall of the tunnel by the other bolt 3.
[0018] Preferably, the bolt 3 is a foot-locking bolt.
[0019] The method for optimizing the parameters of the tunnel support structure adopts the tunnel support structure, including the following steps: S1, establish a finite element numerical calculation model based on the structural parameters of the tunnel excavation process and the construction process. The structural parameters include: steel plate thickness, arch height of the "channel-shaped" steel plate, width of the "channel-shaped" steel plate, width of the arched web 202, width of the flange 201, and pitch. S2, based on the finite element numerical calculation model, conduct numerical simulation analysis on the structural parameters; discretize the finite element numerical calculation model into unit nodes, and calculate the unit nodes through the equilibrium equation, geometric equation, and physical equation. (a) Equilibrium equation: ; ; ; Among them, σ x , σ y , σ z are respectively x, y, z the normal stress components in the τ xy , τ yz <{0000305}> zx are respectively x, y, z the shear stress components in the f x 、f y 、f z are respectively x, y, z the body force components in the (b) Geometric equation: ; ; ; in, ε x , ε y , ε z They are respectively x, y, z Normal strain components in the axial direction, γ xy , γ yz , γ zx They are respectively x, y, z Shear strain components in the axial direction u, v, w They are respectively x, y, z Displacement components in the axial direction; (c) Physical equations: ; ; ; Where E is the elastic modulus. Poisson's ratio; S3, calculate the structural safety factor K, compare the structural safety factor K with the value specified in the code to determine the optimal structural parameters; when the structural safety factor K is greater than the specified value, the corresponding combination of structural parameters is the optimal structural parameters; when the structural safety factor K is less than the specified value, adjust the structural parameters in S2 until the calculated structural safety factor K is greater than the specified value.
[0020] Preferably, in the finite element numerical calculation model of step S1, the surrounding rock adopts an ideal elastic-plastic constitutive relation and the Drucker-Prager nonlinear yield criterion is used for calculation and analysis. The yield criterion is as follows: ; ; ; in: I 1 It is the first invariant of stress; J 2 It is the second invariant of stress deviator; α This is an experimental constant related to the internal friction angle of rocks; K 1 These are experimental constants related to adhesive force.
[0021] 1 is the major principal stress; 2 is the intermediate principal stress; 3 is the minor principal stress.
[0022] Preferably, in the finite element numerical calculation model in step S1, the spiral steel support structure adopts an ideal elastic model simulated by shell elements, and the constitutive relationship is: ; Where: is the stress; is the strain; is the elastic modulus.
[0023] Preferably, for the calculation of the structural safety factor K in step S3, according to the stress state of the "zigzag" steel plate and concrete composite section, it is divided into the following situations: S301, when the neutral axis is within the concrete area, the steel plate is completely in tension, and the basic calculation formula is: ; The calculation formula for the structural safety factor K derived from the basic formula is: ; Where: α r is the reduction coefficient of the structure; R p is the design value of the tensile strength of the steel; A p is the cross-sectional area of the steel plate (per unit width); R w is the design value of the axial compressive strength of the concrete; b is the unit width of the steel plate; h is the thickness of the concrete above the steel plate; e [[ID=...]] is the eccentricity; S302, when the neutral axis is within the "zigzag" steel plate area, part of the steel plate is in tension and part is in compression, and the basic calculation formula is: ; Where: f cd is the design value of the axial compressive strength of the concrete; A s This refers to the cross-sectional area of the steel plate (per unit width). The area of the steel plate in the pressure zone; f d This is the design value for the tensile strength of the steel. This is the design value for the compressive strength of the steel. B The unit width of the steel plate; h c The thickness of the concrete above the steel plate; e It is the eccentricity; Y 1 represents the distance from the resultant tensile stress in the tension zone of the steel plate to the resultant compressive stress in the concrete section of the compression zone; Y 2 represents the distance from the resultant tensile stress in the tension zone of the steel plate to the resultant compressive stress in the steel plate section; The structural safety factor K is solved using an iterative calculation method: S3021, in the first equation In the middle, let K=1, and find the cross-sectional area of the steel plate in the compression zone; S3022, Y1 and Y2 are calculated from the cross-sectional area of the steel plate in the compression zone; S3023, Substitute Y1 and Y2 into the second equation. The new K value is obtained from the result.
[0024] S3024, compare the new K value with the initial K value, and set the convergence rule to be that the difference between the two values is less than 1 × 10. -6 If the conditions are not met, the new K value is used to replace the initial K value and the calculation is repeated until the convergence condition is met; the K value at this time is the structural safety factor.
[0025] S303, when the tension zone is located on the concrete side, first calculate the distance (eccentricity) from the point of application of the axial force to the centroid of the section. e 0: ; in: M For bending moment; N It is the axial force; when e 0 ≤0.20 h When the compressive strength controls the bearing capacity, the formula for calculating the structural safety factor K is: ; in: The longitudinal bending coefficient of the component; α is an experimental constant related to the internal friction angle of the rock; h The height of the cross section; b The width of the cross section; N It is the axial force; R a This refers to the ultimate compressive strength of concrete. when e 0 > 0.20 h When the tensile strength controls the bearing capacity, the formula for calculating the structural safety factor K is: ; in: The longitudinal bending coefficient of the component; h The height of the cross section; b The width of the cross section; R l The tensile ultimate strength of concrete; N This is the axial force.
[0026] The specific embodiments described are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. All equivalent changes made to the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.
Claims
1. A tunnel support structure, characterized in that, The steel support structure (2) is arranged on the inner wall of the tunnel in a spiral structure with the tunnel axis as the center and has a pitch; the steel support structure (2) and the inner wall of the tunnel are provided with the steel mesh (1); the steel support structure (2) comprises an arched web (202) with an opening facing the inner wall of the tunnel, and wing plates (201) arranged on both sides of the opening of the arched web (202); the wing plates (201) and the steel mesh (1) are fixed on the inner wall of the tunnel through the anchor rod structure.
2. The tunnel support structure of claim 1, wherein, The anchor rod structure comprises a plurality of anchor rod units arranged at a distance from each other along the spiral extension direction of the steel support structure (2), each anchor rod unit comprises two anchor rods (3), one of the wing plates (201) of the steel support structure (2) and the steel mesh (1) are fixed on the inner wall of the tunnel through one of the anchor rods (3), and the other wing plate (201) of the steel support structure (2) and the steel mesh (1) are fixed on the inner wall of the tunnel through the other anchor rod (3).
3. The tunnel support structure of claim 1, wherein, The anchor rod (3) is a locking foot anchor rod.
4. A method for optimizing parameters of a tunnel support structure, using the tunnel support structure according to any one of claims 1 to 3, characterized by, The method comprises the following steps: S1, establishing a finite element numerical calculation model based on the structural parameters in the tunnel excavation process and the construction process, the structural parameters comprising: the thickness of the steel plate, the arch height of the "U" shaped steel plate, the width of the "U" shaped steel plate, the width of the arched web (202), the width of the wing plate (201), and the pitch; S2, based on the finite element numerical calculation model, performing numerical simulation analysis on the structural parameters; discretizing the finite element numerical calculation model into element nodes, and calculating the element nodes through balance equations, geometric equations and physical equations; (a) balance equation: ； ； ； wherein σ x , σ y , σ z respectively x, y, z normal stress component in the axial direction, τ xy , τ yz , τ zx respectively x, y, z shear stress component in the axial direction, f x 、f y 、f z respectively x, y, z volume force component in the axial direction; (b) geometric equation: ； ； ； wherein ε x , ε y , ε z respectively x, y, z normal strain components in the axial direction, γ xy , γ yz , γ zx respectively x, y, z shear strain components in the axial direction, u, v, w respectively x, y, z displacement components in the axial direction; (c) physical equation: ； ； ； where E is the modulus of elasticity, is the Poisson's ratio; S3, calculating the structural safety factor K, comparing the structural safety factor K with the specified value to determine the optimal structural parameters; when the structural safety factor K is greater than the specified value, the corresponding structural parameter combination is the optimal structural parameter; when the structural safety factor K is less than the specified value, adjusting the structural parameters in S2 until the calculated structural safety factor K is greater than the specified value.
5. The method of optimizing parameters of a tunnel support structure according to claim 4, wherein, In the step S1, the surrounding rock in the calculation adopts an ideal elastic-plastic constitutive relation, and a Drucker-Prager nonlinear yield criterion is selected for calculation and analysis, and the yield criterion is: ； ； ； wherein: I 1 First invariant of stress; J 2 stress deviatoric second invariant; α an experimental constant related to the internal friction angle of the rock; K 1 an experimental constant related to the cohesive force; 1 is the major principal stress; 2 is the intermediate principal stress; 3 is the minor principal stress.
6. The method of optimizing parameters of a tunnel support structure according to claim 4, wherein, In the step S1, the steel support structure of the spiral structure adopts an ideal elastic model simulated by a shell element, and the constitutive relation is: ； wherein: is stress; to strain; E is the modulus of elasticity.
7. The method of optimizing parameters of a tunnel support structure according to claim 4, wherein, In the step S3, according to the stress state of the "U" shaped steel plate and the concrete composite section, the following cases are divided: S301, when the neutral axis is located in the concrete area, the steel plate is completely in tension, and the basic calculation formula is: ； According to the basic formula, the calculation formula of the structural safety factor K is obtained as: ； wherein: α r Reduction factor for structure; R p Design value for tensile strength of steel A p A is the cross-sectional area of the steel plate; R w For the design value of the concrete axial compressive strength; b For steel sheet unit width; h For steel plate above concrete thickness; e e is the eccentricity; S302, when the neutral axis is located in the "few" steel plate area, a part of the steel plate is in tension, and another part of the steel plate is in compression, and the basic calculation formula is: ； Wherein: f cd For the design value of the concrete axial compressive strength; A s A is the cross-sectional area of the steel plate; Subarea of the steel plate for the compression zone; f d Design value for tensile strength of steel Design value for compressive strength of steel B For steel sheet unit width; h c For steel plate above concrete thickness; e Ecc is the eccentricity; Y 1 is the distance from the resultant tensile stress force of the steel plate tension zone section to the resultant compressive stress force of the concrete section in the compression zone; Y 2 is the distance from the resultant tensile stress force of the steel plate tension zone cross section to the resultant compressive stress force of the steel plate cross section; The structure safety factor K is solved by iteration calculation: S3021, in the first equation K = 1, the cross-sectional area of the steel plate in the compression zone is obtained; S3022, Y1 and Y2 are calculated by the cross-sectional area of the compressed steel plate; S3023, substituting Y1, Y2 into the second equation new K value is obtained in the middle S3024, compare the new K value and the initial K value, set the convergence rule as the difference between the two values is less than 1x10 -6 , if not satisfied, replace the initial K value with the new K value to recalculate until the convergence condition is met; at this time, the K value is the structural safety factor; S303, when the tension zone is located at the concrete side, first calculate the distance from the axial force action point to the section center of gravity (eccentricity) e 0: ； Wherein: M For bending moment; N Ax is the axial force; When e 0 ≤0.20 h When the compressive strength controls the bearing capacity, the calculation formula of the structure safety factor K is: ； Wherein: Cm = coefficient of longitudinal bending of the member; Alpha is an experimental constant related to the internal friction angle of rock; h H is the cross-sectional height; b for the cross-sectional width; N Ax is the axial force; R a fcu is the compressive strength of the concrete; When e 0 0.20 h The tensile strength control bearing capacity, at this time the structure safety factor K formula is: ； Wherein: Cm = coefficient of longitudinal bending of the member; h H is the cross-sectional height; b W is the cross-sectional width; R l is the tensile strength of the concrete. N is the axial force.