A horseshoe-shaped tunnel structure analysis method and device

Abstract

The invention relates to the field of horseshoe tunnel structure analysis, and provides a horseshoe tunnel structure analysis method and device. The method comprises: establishing a tunnel model with a horseshoe profile according to stratum parameters of an area to be excavated; importing the tunnel model into a general finite element analysis program; setting material information and size parameters of a lining; matching the tunnel model with a coordinate axis based on the general finite element analysis program; grouping objects in the tunnel model; setting effective degrees of freedom for analysis; obtaining corresponding spring stiffness according to elastic reaction force coefficients of surrounding rocks; obtaining surrounding rock pressure according to tunnel structure and geological conditions; applying water buoyancy; and obtaining structural internal force calculation results under various working conditions according to the applied loads, thereby accurately obtaining internal force calculation results under various working conditions of the tunnel, solving the difficulty of being unable to accurately perform tunnel internal force analysis in the industry, improving data accuracy, and playing a role in reducing engineering costs.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel engineering, and in particular to a horseshoe-shaped tunnel structure analysis method and device. Background Art

[0002] With the acceleration of urbanization, centralized heating has become an important way of urban heating. As ground space is precious, centralized placement of thermal pipelines in thermal tunnels has become an inevitable choice. However, existing thermal tunnel structural design and analysis tools are mostly based on approximate calculation results of similar projects or manual calculation experience data of predecessors, which limits the accuracy and efficiency of analysis results and increases project costs and risks.

[0003] At present, the structural analysis and calculation of thermal horseshoe tunnels mainly refer to the design or empirical data of single-hole arch culverts. Since the crown of a single-hole arch culvert is an arc and the bottom is a right angle, and the crown of a horseshoe tunnel is a three-centered circle and the bottom is an arc, there is a large error in the structural analysis of a tunnel using a single-hole arch culvert as a reference.

[0004] When using empirical data as a reference, since the empirical data are mostly based on tunnels of specific sizes and were obtained by manual calculations in the early years, the sizes of thermal tunnels have evolved into more forms after years of optimization and improvement. The timeliness and accuracy of empirical data are difficult to compare with computer simulations.

[0005] Based on the above two points, designers often increase the tunnel section or the diameter of the steel bars or arrange the steel bars more densely in order to increase the safety reserve during the design, which often leads to excessively high project costs or even the inability to implement the project. Summary of the invention

[0006] In order to solve the technical problem in the prior art that designers often increase the tunnel section or the steel bar diameter or the steel bar arrangement in order to increase the safety reserve during design, which often leads to excessively high project costs or even the inability to implement the project, the embodiment of the present invention provides a horseshoe tunnel structure analysis method and device. The technical solution is as follows:

[0007] In one aspect, a horseshoe tunnel structure analysis method is provided, the method comprising:

[0008] According to the stratum parameters of the area to be excavated, a tunnel model with a horseshoe-shaped cross section is established;

[0009] Import the tunnel model into a common finite element analysis program;

[0010] Set the material information and size parameters of the lining;

[0011] Based on a general finite element analysis program, the tunnel model is matched with the coordinate axes;

[0012] Group the objects in the tunnel model;

[0013] Set the effective degrees of freedom for the analysis;

[0014] According to the elastic reaction coefficient of the surrounding rock, the corresponding spring stiffness is obtained;

[0015] Obtain surrounding rock pressure based on tunnel structure and geological conditions;

[0016] Apply water buoyancy;

[0017] Based on the applied loads, the structural internal force calculation results under various working conditions are analyzed.

[0018] Optionally, establishing the tunnel model with a horseshoe-shaped cross-section includes: drawing the tunnel model with a horseshoe-shaped cross-section using computer-aided design software.

[0019] Optionally, establishing the tunnel model with a horseshoe-shaped cross-section further includes: dividing the arc and the straight line into equal parts at specific intervals.

[0020] Optionally, setting effective degrees of freedom for analysis includes: performing a two-dimensional analysis on the grouped objects.

[0021] Optionally, according to the elastic reaction force coefficient of the surrounding rock, the corresponding spring stiffness is obtained including:

[0022] Determine the frame wire spring according to the elastic reaction coefficient of the surrounding rock;

[0023] Define the spring type as simple-decoupled and determine the spring stiffness based on the surrounding rock type.

[0024] Optionally, according to the tunnel structure and geological conditions, obtaining the surrounding rock pressure includes: calculating and inputting the surrounding rock pressure in the vertical direction and the horizontal direction.

[0025] Optionally, calculate and input vertical rock pressure, including:

[0026] Formula 1

[0027] Formula 2

[0028] Formula 3

[0029] Where, q is the surrounding rock pressure in the vertical direction, in kPa;

[0030] ——weight of surrounding rock, unit: kN / m 3 ;

[0031] h——the height of the tunnel top from the ground, in m;

[0032] ——friction angle on both sides of the top soil column, unit: °;

[0033] B——tunnel span, in m;

[0034] ——lateral pressure coefficient, unitless;

[0035] ——Calculated friction angle of surrounding rock, unit: °;

[0036] ——Rupture angle when maximum thrust is generated, unit: °.

[0037] Optionally, calculate and input the horizontal rock pressure, including:

[0038] Formula 4

[0039] in, ——horizontal surrounding rock pressure, unit: kPa;

[0040] γ——weight of surrounding rock, unit: kN / m 3 ;

[0041] ——The distance from any point inside or outside to the ground, in meters;

[0042] λ——lateral pressure coefficient, unitless.

[0043] Optionally, applying water buoyancy includes:

[0044] Apply uniformly distributed line loads to all frame objects, obtain the centroid elevation of each frame object through data calculation software, and sort them from small to large;

[0045] Utilize interactive database editing to export frame loads;

[0046] Modify the uniformly distributed line load of each frame object in the data calculation software;

[0047] First sort the loads, then paste the centroid data, and then edit the calculation formula to obtain the load corresponding to the water buoyancy.

[0048] On the one hand, a horseshoe-shaped tunnel structure analysis device is also provided, comprising:

[0049] A modeling module, used to establish a tunnel model with a horseshoe-shaped profile according to the stratum parameters of the area to be excavated;

[0050] Import module for importing tunnel models into common finite element analysis programs;

[0051] Parameter setting module, used to set the material information and size parameters of the lining;

[0052] An analysis module for matching the tunnel model to the coordinate axes based on a general finite element analysis program;

[0053] A grouping module, used to group objects in the tunnel model;

[0054] The degree of freedom acquisition module is used to set the effective degrees of freedom for analysis;

[0055] A determination module is used to obtain the corresponding spring stiffness according to the elastic reaction force coefficient of the surrounding rock;

[0056] The pressure acquisition module is used to obtain the surrounding rock pressure according to the tunnel structure and geological conditions;

[0057] A water buoyancy determination module, used for applying water buoyancy;

[0058] The calculation module is used to analyze and obtain the calculation results of the structural internal forces under various working conditions based on the applied loads.

[0059] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0060] The horseshoe tunnel structure analysis method provided by the embodiment of the present invention can realize the accurate modeling of the thermal horseshoe tunnel, accurately apply the load, and accurately obtain the internal force calculation results of the tunnel under various working conditions through structural finite element analysis, thus solving the difficulty of accurately performing tunnel internal force analysis in the industry. At the same time, the structural section and reinforcement obtained by the method of the present invention are closer to the actual engineering situation, and the data obtained by the analysis are more accurate, which makes up for the shortcomings of the previous design methods and can play a role in reducing engineering costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0062] Figure 1 This is one of the flow charts of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention;

[0063] Figure 2 This is a second flow chart of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention;

[0064] Figure 3 It is a schematic diagram of a horseshoe-shaped tunnel cross-section structure provided by an embodiment of the present invention;

[0065] Figure 4 This is a flow chart of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention;

[0066] Figure 5 is a schematic diagram of a vertical surrounding rock structure provided by an embodiment of the present invention;

[0067] Figure 6 This is a fourth flow chart of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention;

[0068] Figure 7 This is a fifth flow chart of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention;

[0069] Figure 8 is a schematic diagram of applying a load provided by an embodiment of the present invention;

[0070] Fig. 9 is a schematic diagram of internal force calculation results provided by an embodiment of the present invention;

[0071] Fig.10 It is a block diagram of a horseshoe tunnel structure analysis device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0072] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0073] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either of the two.

[0074] In the embodiments of the present invention, sometimes a subscript such as W1 may be mistakenly written as a non-subscript such as W1. When the difference is not emphasized, the meanings to be expressed are consistent.

[0075] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0076] An embodiment of the present invention provides a horseshoe tunnel structure analysis method. Figure 1 This is one of the flow charts of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention, please refer to Figure 1 The processing flow of the method may include the following steps:

[0077] 101. According to the geological parameters of the area to be excavated, a tunnel model with a horseshoe-shaped cross-section is established.

[0078] 102. Import the tunnel model into a general finite element analysis program.

[0079] 103. Set the material information and size parameters of the lining.

[0080] 104. Based on the general finite element analysis program, the tunnel model is matched with the coordinate axes.

[0081] 105. Group the objects in the tunnel model.

[0082] 106. Set the effective degrees of freedom for the analysis.

[0083] 107. According to the elastic reaction coefficient of the surrounding rock, the corresponding spring stiffness is obtained.

[0084] 108. The surrounding rock pressure is obtained based on the tunnel structure and geological conditions.

[0085] 109. Apply water buoyancy.

[0086] 110. Based on the applied load, the calculation results of the structural internal forces under various working conditions are analyzed.

[0087] The horseshoe tunnel structure analysis method provided by the embodiment of the present invention can realize the accurate modeling of the thermal horseshoe tunnel, accurately apply the load, and accurately obtain the internal force calculation results of the tunnel under various working conditions through structural finite element analysis, thus solving the difficulty of accurately performing tunnel internal force analysis in the industry. At the same time, the structural section and reinforcement obtained by the method of the present invention are closer to the actual engineering situation, and the data obtained by the analysis are more accurate, which makes up for the shortcomings of the previous design methods and can play a role in reducing engineering costs.

[0088] In one embodiment provided by the present invention, establishing a tunnel model with a horseshoe-shaped cross-section includes: drawing the tunnel model with a horseshoe-shaped cross-section using computer-aided design software.

[0089] Furthermore, in an embodiment provided by the present invention, establishing a tunnel model with a horseshoe-shaped cross-section also includes: dividing the arc and the straight line into equal parts at specific intervals.

[0090] In one embodiment provided by the present invention, setting the effective degrees of freedom of analysis includes: performing a two-dimensional analysis on the grouped objects.

[0091] In an embodiment provided by the present invention, the corresponding spring stiffness is obtained according to the elastic reaction force coefficient of the surrounding rock, including:

[0092] Determine the frame wire spring according to the elastic reaction coefficient of the surrounding rock;

[0093] Define the spring type as simple-decoupled and determine the spring stiffness based on the surrounding rock type.

[0094] In an embodiment provided by the present invention, obtaining the surrounding rock pressure according to the tunnel structure and geological conditions includes: calculating and inputting the surrounding rock pressure in the vertical direction and the horizontal direction.

[0095] Furthermore, in an embodiment provided by the present invention, calculating and inputting the surrounding rock pressure in the vertical direction includes:

[0096] Formula 1

[0097] Formula 2

[0098] Formula 3

[0099] Where, q is the surrounding rock pressure in the vertical direction, in kPa;

[0100] ——weight of surrounding rock, unit: kN / m 3 ;

[0101] h——the height of the tunnel top from the ground, in m;

[0102] ——friction angle on both sides of the top soil column, unit: °;

[0103] B——tunnel span, in m;

[0104] ——lateral pressure coefficient, unitless;

[0105] ——Calculated friction angle of surrounding rock, unit: °;

[0106] ——Rupture angle when maximum thrust is generated, unit: °.

[0107] In one embodiment provided by the present invention, the surrounding rock pressure in the horizontal direction is calculated and inputted.

[0108] include:

[0109] Formula 4

[0110] in, ——horizontal surrounding rock pressure, unit: kPa;

[0111] γ——surrounding rock mass, unit: kN / m 3 ;

[0112] ——The distance from any point inside or outside to the ground, in meters;

[0113] λ——lateral pressure coefficient, unitless.

[0114] In one embodiment provided by the present invention, applying water buoyancy includes:

[0115] Apply uniformly distributed line loads to all frame objects, obtain the centroid elevation of each frame object through data calculation software, and sort them from small to large;

[0116] Utilize interactive database editing to export frame loads;

[0117] Modify the uniformly distributed line load of each frame object in the data calculation software;

[0118] First sort the loads, then paste the centroid data, and then edit the calculation formula to obtain the load corresponding to the water buoyancy.

[0119] The present invention provides a horseshoe tunnel structure analysis method. Figure 2 This is a flow chart of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention. Figure 2 , the method comprising:

[0120] 201. According to the geological parameters of the area to be excavated, a tunnel model with a horseshoe-shaped profile is established.

[0121] In this step, the tunnel model with a horseshoe profile can be established based on the stratigraphic parameters of the area to be excavated, such as geological conditions, rock types, soil characteristics, groundwater levels, etc. Based on the above conditions, ensure that the model accurately reflects the geometry and size of the tunnel. The tunnel model should include key parts such as lining and surrounding rock, and consider design parameters such as tunnel burial depth and span. For example, the vault of a horseshoe-shaped tunnel is a three-center circle and the bottom is an arc.

[0122] The step of establishing a tunnel model with a horseshoe-shaped cross section includes: drawing a tunnel model with a horseshoe-shaped cross section using computer-aided design software.

[0123] Based on the above conditions, a tunnel model with a horseshoe-shaped profile is established using computer-aided design software or other modeling tools to ensure that the model accurately reflects the geometry and size of the tunnel. For example, a three-dimensional modeling software such as AutoCAD, SolidWorks, etc. can be used to establish a tunnel model with a horseshoe-shaped profile according to the formation parameters and tunnel design requirements.

[0124] Furthermore, in an embodiment provided by the present invention, establishing a tunnel model with a horseshoe-shaped cross-section also includes: dividing the arc and the straight line into equal parts at specific intervals.

[0125] In CAD or other modeling software, you can use drawing tools to draw the basic shapes of the horseshoe section, such as lines, arcs, etc. Then, use the software's equal division function to divide the arcs and straight lines into equal parts at specific intervals, such as "equal division of line segments" or "equal division of arcs".

[0126] 202. Import the tunnel model into a general finite element analysis program.

[0127] Specifically, the established tunnel model is imported into a general finite element analysis program for subsequent structural analysis. For example, it can be COMSOL Multiphysics, Abaqus, Optistruct or ANSYS. Among them, COMSOL Multiphysics is widely used in scientific research and engineering calculations, and is particularly good at simulating various physical processes. It is famous for its efficient computing performance and excellent multi-field bidirectional direct coupling analysis capabilities. Abaqus is powerful and can simulate from simple linear analysis to complex nonlinear problems. It is suitable for processing various engineering materials and system-level analysis. Optistruct focuses on structural analysis and optimization, and is suitable for linear and nonlinear structural problems under static and dynamic load conditions. ANSYS is known for its task-based interface and powerful technology, and is suitable for basic operations and advanced simulations.

[0128] In this step, the global upward direction can be defined as Y in the general finite element analysis program, with the length unit in mm, and the center of the invert is translated to the origin of the coordinate system. The invert is a reverse arch structure set at the bottom of the tunnel to improve the stress conditions of the upper support structure. It is one of the main components of the tunnel structure. On the one hand, it effectively transfers the stratum pressure above the tunnel to the underground through the tunnel side wall structure or the load on the road surface, and also effectively resists the reaction force from the stratum below the tunnel.

[0129] 203. Set the material information and size parameters of the lining.

[0130] See also Figure 3

[0131] In this step, the formation information of the lining, such as elastic modulus, Poisson's ratio, density, internal friction angle, cohesion, etc., can be determined based on the above-mentioned formation parameters and input into the general finite element analysis program. At the same time, the material, cross-sectional shape, thickness and other dimensional parameters of the lining are specified in the general finite element analysis program. Specifically, it may include concrete strength grade, lining thickness, reinforcement, etc. In addition, boundary conditions, such as bottom fixed constraints, side wall constraints, etc., can also be set according to the actual engineering conditions.

[0132] 204. Based on the general finite element analysis program, the tunnel model is matched with the coordinate axes.

[0133] Based on the general finite element analysis program, the tunnel model is matched with the coordinate axes to ensure the correct direction and coordinate system of the analysis.

[0134] Specifically, this step can be to select the entire model, edit the advanced local axis, select the plane, define the plane reference vector as the coordinate axis, define GLOBAL as the coordinate system, define -Y as the main direction of the coordinate axis, and stretch the view to check that the coordinate axis direction is correct.

[0135] 205. Group the objects in the tunnel model.

[0136] In order to facilitate subsequent operations and analysis, the objects in the tunnel model are grouped. For example, the upper arc segment can be defined as the TOP group, the middle part as the MID group, and the lower part as the BOT group, and the local 2 axes can be modified to point uniformly inward.

[0137] This step is used to group objects in the tunnel model, such as lining and surrounding rock, to facilitate subsequent operations.

[0138] 206. Set the effective degrees of freedom for the analysis.

[0139] In finite element analysis, degrees of freedom (DOF) usually refers to the number of parameters or variables that can be changed independently in a system. These parameters or variables may be displacements, rotations, stresses, etc. Effective degrees of freedom are those degrees of freedom that have a real impact or contribution to the analysis results.

[0140] In one embodiment provided by the present invention, setting the effective degrees of freedom for analysis includes: performing a two-dimensional analysis on the grouped objects. Generally, for the two-dimensional analysis, UX (horizontal displacement) and UZ (vertical displacement) can be selected as effective degrees of freedom. This step can avoid unnecessary error prompts of out-of-plane instability in the three-dimensional analysis by performing a two-dimensional analysis on the objects.

[0141] 207. According to the elastic reaction coefficient of the surrounding rock, the corresponding spring stiffness is obtained.

[0142] In the structural design of underground projects, the interaction between the surrounding rock and the supporting structure is an important consideration, where the supporting structure includes the frame, lining, etc. This interaction is usually simulated by introducing a wire spring model, where the wire spring represents the elastic reaction force of the surrounding rock on the supporting structure.

[0143] The elastic reaction coefficient of the surrounding rock describes the relationship between the reaction force generated by the surrounding rock on the support structure and the deformation of the support structure. This coefficient is a function of the physical properties of the surrounding rock, geological conditions and stress state. Among them, the physical properties of the surrounding rock include elastic modulus, Poisson's ratio, etc., and the geological conditions include rock formation type, rock formation thickness, rock formation direction, etc.

[0144] In this step, the distribution of surrounding rock pressure can be calculated based on the tunnel structure and geological conditions, taking into account factors such as the deadweight and lateral pressure of the surrounding rock.

[0145] Figure 4 This is a flow chart of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention. Please refer to Figure 4 In one embodiment provided by the present invention, the corresponding spring stiffness is obtained according to the elastic reaction force coefficient of the surrounding rock, including:

[0146] 2071. Determine the frame wire spring based on the elastic reaction coefficient of the surrounding rock.

[0147] In the simulation, in order to consider the supporting effect of the surrounding rock on the support structure, wire springs are set at appropriate locations of the support structure, for example, at the nodes or edges of the frame. The stiffness and damping parameters of these wire springs are determined according to the elastic reaction coefficient of the surrounding rock.

[0148] 2072. Define the spring type as simple-decoupled and determine the spring stiffness based on the surrounding rock type.

[0149] Among them, the simple-decoupled spring assumes that the stiffness of the spring in each direction is independent, that is, the deformation in one direction does not affect the stiffness in other directions.

[0150] Different types of surrounding rock have different physical properties, so the corresponding spring stiffness will also be different. Generally, hard rock has a larger elastic modulus and a corresponding spring stiffness, while soft rock or soil has a smaller elastic modulus and a corresponding spring stiffness. Therefore, it is necessary to determine the spring stiffness.

[0151] Use springs to simulate the interaction between surrounding rock and lining, specify frame wire springs, and define the spring type as simple-decoupled, so that the elastic reaction coefficient of the surrounding rock can be obtained. Specifically, according to the surrounding rock type, the spring stiffness k can be determined by formula or experimental data. Enter the spring stiffness k per unit length in kN / m / m. Among them, the spring type is a single compression spring, which can only withstand pressure but not tension. The spring stiffness will be used to simulate the elastic support of the surrounding rock to the tunnel structure.

[0152] Furthermore, the tension direction is parallel to the linear local axis 2Axis, where in the simulation, the spring generates a reaction force when the support structure is stretched along the second axis of its local coordinate system, which is usually called the y-axis or vertical axis. In underground engineering, this usually corresponds to the deformation of the support structure in a direction perpendicular to the axis of the tunnel or cavern.

[0153] Next, based on the tunnel structure and geological conditions, the surrounding rock pressure, including horizontal pressure and vertical pressure, is calculated and applied.

[0154] 208. Calculate and input the vertical surrounding rock pressure based on the tunnel structure and geological conditions.

[0155] See also Figure 5 In this step, the load direction is selected as the gravity projection direction, and the vertical surrounding rock pressure is calculated as follows:

[0156] Formula 1

[0157] Formula 2

[0158] Formula 3

[0159] Where, q is the surrounding rock pressure in the vertical direction, in kPa;

[0160] ——weight of surrounding rock, unit: kN / m 3 ;

[0161] h——the height of the tunnel top from the ground, in m;

[0162] ——friction angle on both sides of the top soil column, unit: °;

[0163] B——tunnel span, in m;

[0164] ——lateral pressure coefficient, unitless;

[0165] ——Calculated friction angle of surrounding rock, unit: °;

[0166] ——Rupture angle when maximum thrust is generated, unit: °.

[0167] 209. Calculate and input the horizontal surrounding rock pressure based on the tunnel structure and geological conditions.

[0168] In this step, select the horizontal projection direction for the load direction. When the load direction is to the left, enter a positive value. When the load direction is to the right, enter a negative value. The horizontal surrounding rock pressure is calculated as follows:

[0169] Formula 4

[0170] in, ——horizontal surrounding rock pressure, unit: kPa;

[0171] γ——surrounding rock mass, unit: kN / m3 ;

[0172] ——The distance from any point inside or outside to the ground, in meters;

[0173] λ——lateral pressure coefficient, unitless.

[0174] 210. Apply water buoyancy.

[0175] When performing finite element analysis of tunnels or other underground structures, water buoyancy is a load that cannot be ignored. Especially in areas with high water levels or shallow buried structures, water buoyancy may have a significant impact on the safety and stability of the structure. Therefore, in this step, the influence of groundwater is considered. If the tunnel is underwater or subject to the buoyancy of water, the corresponding water buoyancy load needs to be applied to the model to ensure the accuracy of the analysis results. The corresponding loads obtained are shown in Table 1.

[0176] Table 1

[0177]

[0178] Figure 6 This is a flow chart of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention, see Figure 6 Specifically, the step includes:

[0179] 2101. Apply uniformly distributed line loads to all frame objects, obtain the centroid elevation of each frame object through data calculation software, and sort them from small to large.

[0180] In this step, it is necessary to identify which objects in the model, such as tunnel linings, beams, columns, etc., will be subject to the buoyancy of water. Use the built-in functions of data calculation software, such as ANSYS, Abaqus, etc., to calculate the centroid elevation of each frame object. Sort the calculated centroid elevations in ascending order for easy subsequent processing.

[0181] 2102. Use the interactive database to edit and export frame loads.

[0182] In this step, if there is not already a database for storing structural loads, it is necessary to create one. This database can be a spreadsheet, database software, or a dedicated data management system. The calculated uniformly distributed load data for the frame objects is exported from the data calculation software and imported into the database. In the database, the load data can be easily edited and modified to meet different analysis requirements. In this way, the loads can be further edited and processed to meet specific analysis requirements.

[0183] 2103. Modify the uniformly distributed line load of each framework object in the data calculation software.

[0184] In this step, the modified load data in the database is re-imported into the data calculation software. After importing, the accuracy of the data needs to be verified to ensure that no data is lost or distorted due to errors during the import process. According to the new load data, the corresponding parameters of the model are modified in the data calculation software to ensure that the model can correctly reflect the effect of water buoyancy.

[0185] 2104. Sort the loads first, then paste the centroid data, and then edit the calculation formula to obtain the load corresponding to the water buoyancy.

[0186] In this step, check and confirm again that the load data has been sorted in the order of centroid elevation. In the data calculation software, paste the sorted centroid data to the corresponding position for use in subsequent calculations. According to the calculation principle of water buoyancy, edit or create a calculation formula in the data calculation software, where the calculation principle of water buoyancy can be Archimedes principle, etc. This formula will be used to calculate the magnitude of water buoyancy based on the water level and the geometric dimensions of the structure. Using the edited calculation formula, calculate the water buoyancy of each frame object. This calculation process may need to be iterative or cyclic to ensure that all possible water level changes and structural deformations are taken into account. Apply the calculated water buoyancy as a load to the corresponding frame object. In the data calculation software, this can usually be achieved by applying the load data to the corresponding nodes or elements of the model.

[0187] Through the above steps, water buoyancy loads can be accurately applied, thus more realistically simulating the stress conditions of the tunnel when it is underwater or under the action of water buoyancy. This helps to improve the accuracy of structural analysis and provide a more reliable basis for tunnel design and construction.

[0188] 211. Based on the applied load, the calculation results of the structural internal forces under various working conditions are analyzed.

[0189] In a general finite element analysis program, set the effective degrees of freedom for the analysis and start the analysis calculation.

[0190] According to the project requirements, the internal force, displacement and other parameters of the tunnel under different working conditions are analyzed.

[0191] Extract analysis results, including internal force cloud diagram, displacement cloud diagram, stress-strain curve, etc.

[0192] Based on the analysis results, the stability and safety of the tunnel structure are evaluated.

[0193] Based on the analysis results, the tunnel structure is optimized, such as adjusting the lining thickness and reinforcement.

[0194] Consider the uncertainties in the construction process and conduct sensitivity analysis and risk assessment.

[0195] The optimized tunnel design scheme is applied to actual projects to guide tunnel construction and monitoring.

[0196] The accuracy and reliability of the analysis method are further verified through on-site monitoring data feedback.

[0197] Figure 7 This is a flow chart of a horseshoe tunnel structure analysis method provided by an embodiment of the present invention, see Figure 7 In this step, it specifically includes:

[0198] 2111. Copy the column data in the calculation software and paste it into the interactive data table of the general finite element analysis program to complete the application of the load.

[0199] See Table 2 and Figure 8 Specifically, in the data calculation software, ensure that all load data that need to be applied to the model have been obtained and organized into a column data format that can be copied.

[0200] Table 2

[0201]

[0202] In the data calculation software, select the column data to be copied and use the copy command, for example, Ctrl+C, to copy the data to the clipboard.

[0203] Open a general finite element analysis program, such as ANSYS, Abaqus, SAP2000, etc., and load or create a model.

[0204] In finite element analysis programs, find interactive data forms for entering or editing load data. This is usually an editable table interface that allows the user to enter and modify various parameters and loads of the model.

[0205] In the interactive data table, locate the location where you need to enter the loads and use the paste command, for example, Ctrl+V, to paste the data previously copied from the calculation software into the corresponding column. Make sure that the format and units of the data are consistent with the requirements of the finite element analysis program.

[0206] After pasting the data, double-check that it has been entered correctly and verify the accuracy and completeness of the data.

[0207] Once the data has been correctly entered, calculations can be run in the FEA program to complete the application of loads and loading of the model.

[0208] 2112. Define the load combination according to the relevant specifications, the working condition type is nonlinear, and the calculation results of the structural internal force under various working conditions are obtained based on analysis.

[0209] In this step, see Fig. 9 , you need to understand and be familiar with the relevant specifications of the industry or project you are engaged in. These specifications usually specify the values ​​and calculation methods of load combinations.

[0210] In the finite element analysis program, different load combinations are defined according to the requirements of the specification. This usually includes considering the combination of different load types and the combination of different load factors. Among them, the above-mentioned different load types can be dead load, live load, wind load, temperature load, etc.

[0211] For some complex structures or situations that require more precise analysis, it may be necessary to set the operating condition type to nonlinear, and then run the finite element analysis program to start calculating the structural internal forces under various operating conditions.

[0212] After the analysis is completed, the calculation results of the internal forces of the structure under various working conditions can be viewed and exported. These results usually include various stresses, strains, displacements and other parameters, which can help evaluate the safety and stability of the structure. If necessary, the tunnel design can be optimized, such as adjusting the lining thickness, changing the support method, etc., to meet the engineering requirements.

[0213] The tunnel model was subjected to structural finite element analysis using a general finite element analysis program. During the analysis, various load conditions, such as deadweight, surrounding rock pressure, water buoyancy, etc., were considered to calculate the internal force distribution of the tunnel under different conditions.

[0214] The horseshoe tunnel structure analysis method provided by the embodiment of the present invention can realize the accurate modeling of the thermal horseshoe tunnel, accurately apply the load, and accurately obtain the internal force calculation results of the tunnel under various working conditions through structural finite element analysis, thus solving the difficulty of accurately performing tunnel internal force analysis in the industry. At the same time, the structural section and reinforcement obtained by the method of the present invention are closer to the actual engineering situation, and the data obtained by the analysis are more accurate, which makes up for the shortcomings of the previous design methods and can play a role in reducing engineering costs.

[0215] Furthermore, the horseshoe tunnel structure analysis method provided by the present invention can be widely used in urban subways, highway tunnels, water conservancy projects and other fields.

[0216] In practical applications, model parameters and analysis steps can be adjusted according to specific engineering conditions to meet the needs of different projects.

[0217] Fig.10 1 is a block diagram of a horseshoe tunnel structure analysis device provided by an embodiment of the present invention, and the device is used in a horseshoe tunnel structure analysis method. Fig.10The device includes a modeling module 1010, an import module 1020, a parameter setting module 1030, an analysis module 1040, a grouping module 1050, a degree of freedom acquisition module 1060, a determination module 1070, a pressure acquisition module 1080, a water buoyancy determination module 1090 and a calculation module 10100. Among them:

[0218] A modeling module 1010 is used to establish a tunnel model with a horseshoe-shaped cross section according to the stratum parameters of the area to be excavated;

[0219] An import module 1020, for importing the tunnel model into a general finite element analysis program;

[0220] Parameter setting module 1030, used to set material information and size parameters of lining;

[0221] An analysis module 1040, for matching the tunnel model with the coordinate axis based on a general finite element analysis program;

[0222] A grouping module 1050, used to group objects in the tunnel model;

[0223] A degrees of freedom acquisition module 1060 is used to set effective degrees of freedom for analysis;

[0224] A determination module 1070 is used to obtain a corresponding spring stiffness according to the elastic reaction force coefficient of the surrounding rock;

[0225] The pressure acquisition module 1080 is used to obtain the surrounding rock pressure according to the tunnel structure and geological conditions;

[0226] A water buoyancy determination module 1090, for applying water buoyancy;

[0227] The calculation module 10100 is used to analyze and obtain the calculation results of the structural internal force under various working conditions according to the applied load.

[0228] The horseshoe tunnel structure analysis device provided by the embodiment of the present invention can realize accurate modeling of thermal horseshoe tunnels, accurately apply loads, and accurately obtain the internal force calculation results of the tunnel under various working conditions through structural finite element analysis, thereby solving the difficulty of accurately performing tunnel internal force analysis in the industry. At the same time, the structural section and reinforcement obtained by the method of the present invention are closer to the actual engineering situation, and the data obtained by analysis are more accurate, which makes up for the shortcomings of previous design methods and can reduce engineering costs.

[0229] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0230] In the present invention, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0231] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0232] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A horseshoe tunnel structure analysis method, characterized in that: The method comprises: According to the stratum parameters of the area to be excavated, a tunnel model with a horseshoe-shaped cross section is established; Importing the tunnel model into a general finite element analysis program; Set the material information and size parameters of the lining; Based on the general finite element analysis program, matching the tunnel model with coordinate axes; Grouping objects in the tunnel model; Set the effective degrees of freedom for the analysis; According to the elastic reaction coefficient of the surrounding rock, the corresponding spring stiffness is obtained; Obtain surrounding rock pressure based on tunnel structure and geological conditions; Apply water buoyancy; According to the applied load, the calculation results of the structural internal force under various working conditions are analyzed; Wherein, obtaining the surrounding rock pressure according to the tunnel structure and geological conditions includes: calculating and inputting the surrounding rock pressure in the vertical direction and the horizontal direction; Calculate and input vertical rock pressure, including: Where, q is the surrounding rock pressure in the vertical direction, in kPa; γ——surrounding rock mass, unit: kN / m 3 ; h——the height of the tunnel top from the ground, in m; θ——friction angle on both sides of the top soil column, unit: °; B——tunnel span, in m; λ——lateral pressure coefficient, no unit; ——Calculated friction angle of surrounding rock, unit: °; β——rupture angle when maximum thrust is generated, unit: °; Calculate and input the horizontal surrounding rock pressure, including: e i = γh i λ Formula 4 Among them, e i ——horizontal surrounding rock pressure, unit: kPa; γ——weight of surrounding rock, unit: kN / m 3 ; h i ——The distance from any point inside or outside to the ground, in meters; λ——lateral pressure coefficient, no unit; The applying of water buoyancy comprises: Applying uniformly distributed line loads to all framework objects, including tunnel lining, beams, and columns; Obtain the centroid elevation of each frame object through data calculation software and sort them from small to large; Establish an interactive database for storing structural loads; importing uniformly distributed line loads of frame objects into the database; Utilize interactive database editing to export frame loads; Modify the uniformly distributed line load of each frame object in the data calculation software; First sort the loads, then paste the centroid data, and then edit the calculation formula to calculate the water buoyancy of each frame object; The calculated water buoyancy is applied as a load to the corresponding frame object to obtain the load corresponding to the water buoyancy.

2. The horseshoe tunnel structure analysis method according to claim 1, characterized in that: The step of establishing the tunnel model with a horseshoe-shaped cross section comprises: drawing the tunnel model with a horseshoe-shaped cross section using computer-aided design software.

3. The horseshoe tunnel structure analysis method according to claim 2, characterized in that: The step of establishing a tunnel model with a horseshoe-shaped cross section further includes: dividing the arc and the straight line into equal parts at specific intervals.

4. The horseshoe tunnel structure analysis method according to claim 1, characterized in that: The setting of effective degrees of freedom for analysis includes: performing two-dimensional analysis on the grouped objects.

5. The horseshoe tunnel structure analysis method according to claim 1, characterized in that: The corresponding spring stiffness obtained according to the elastic reaction force coefficient of the surrounding rock includes: Determine the frame wire spring according to the elastic reaction coefficient of the surrounding rock; Define the spring type as simple-decoupled and determine the spring stiffness based on the surrounding rock type.

6. A horseshoe-shaped tunnel structure analysis device, characterized in that: The device comprises: A modeling module, used to establish a tunnel model with a horseshoe-shaped profile according to the stratum parameters of the area to be excavated; An import module for importing the tunnel model into a general finite element analysis program; Parameter setting module, used to set the material information and size parameters of the lining; an analysis module for matching the tunnel model with coordinate axes based on the general finite element analysis program; A grouping module, used for grouping objects in the tunnel model; The degree of freedom acquisition module is used to set the effective degrees of freedom for analysis; A determination module is used to obtain the corresponding spring stiffness according to the elastic reaction force coefficient of the surrounding rock; The pressure acquisition module is used to obtain the surrounding rock pressure according to the tunnel structure and geological conditions; A water buoyancy determination module, used for applying water buoyancy; The calculation module is used to analyze and obtain the calculation results of the structural internal forces under various working conditions according to the applied loads; Wherein, obtaining the surrounding rock pressure according to the tunnel structure and geological conditions includes: calculating and inputting the surrounding rock pressure in the vertical direction and the horizontal direction; Calculate and input vertical rock pressure, including: Where, q is the surrounding rock pressure in the vertical direction, in kPa; γ——weight of surrounding rock, unit: kN / m 3 ; h——the height of the tunnel top from the ground, in m; θ——friction angle on both sides of the top soil column, unit: °; B——tunnel span, in m; λ——lateral pressure coefficient, no unit; ——Calculated friction angle of surrounding rock, unit: °; β——rupture angle when maximum thrust is generated, unit: °; Calculate and input the horizontal surrounding rock pressure, including: e i = γh i λ Formula 4 Among them, e i ——horizontal surrounding rock pressure, unit: kPa; γ——weight of surrounding rock, unit: kN / m 3 ; h i ——The distance from any point inside or outside to the ground, in meters; λ——lateral pressure coefficient, no unit; The applying of water buoyancy comprises: Applying uniformly distributed line loads to all framework objects, including tunnel lining, beams, and columns; Obtain the centroid elevation of each frame object through data calculation software and sort them from small to large; Establish an interactive database for storing structural loads; importing uniformly distributed line loads of frame objects into the database; Utilize interactive database editing to export frame loads; Modify the uniformly distributed line load of each frame object in the data calculation software; First sort the loads, then paste the centroid data, and then edit the calculation formula to calculate the water buoyancy of each frame object; The calculated water buoyancy is applied as a load to the corresponding frame object to obtain the load corresponding to the water buoyancy.

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