Super-large-span tunnel component-based design method, design device and construction method

Abstract

The invention provides a super-large-span tunnel component design method, a design device and a construction method, and relates to the technical field of tunnel design, the design method comprises the steps that parameter information of a super-large-span tunnel is taken, and the parameter information comprises surrounding rock mechanical parameters, tunnel geometric parameters and supporting material parameters; a finite element model is constructed according to the parameter information, the design parameters of the finite element model comprise the anchor cable arrangement parameters of each excavation part of the super-large-span tunnel, and the anchor cable arrangement parameters comprise the circumferential spacing, the longitudinal spacing and the prestress of each anchor cable; setting an excavation sequence of the excavation parts; and according to the excavation sequence and the finite element model, carrying out parameter optimization on the anchor cable arrangement parameters of each excavation part to obtain optimal design parameters. The method solves the problem that an existing support design method does not consider mutual influence between different excavation stages and component parts.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel design, and in particular to a design method, a design device and a construction method for componentizing an ultra-large span tunnel. Background Art

[0002] With the continuous development of urban transportation infrastructure, the scale of tunnel construction is constantly expanding. Ultra-long-span tunnels (with spans far larger than conventional tunnels) have gradually become a key development direction in tunnel construction due to their potential to improve traffic capacity and reduce construction costs. However, ultra-long-span tunnels face numerous technical challenges during construction, including poor structural stability due to their large spans, severe surrounding rock deformation, and insufficient initial support bearing capacity. These challenges can easily lead to geological hazards such as surrounding rock instability and initial support failure.

[0003] Currently, common design methods, such as double-sidewall pilot tunneling, CD, and CRD, fail to fully account for the structural complexity and construction disturbance effects of ultra-large-span tunnels. In particular, anchor cable support design lacks systematic optimization methods for the interactions between different excavation stages and component locations, which can easily lead to redundant or insufficient support, impacting construction efficiency and structural safety. Furthermore, traditional design methods fail to fully integrate modern numerical simulation and intelligent optimization techniques, making them unable to meet the requirements of ultra-large-span tunnels for refined, component-based, and comprehensive design.

[0004] Therefore, there is an urgent need for a design and construction method that can systematically consider the construction sequence, the coupling effect of support structure and surrounding rock, and realize the automatic optimization and combination of anchor cable parameters, thereby improving design efficiency and engineering safety. Summary of the Invention

[0005] The purpose of the present invention is to provide a design method, design device and construction method for ultra-large span tunnel components to improve the above-mentioned problems. To achieve the above-mentioned purpose, the technical solutions adopted by the present invention are as follows:

[0006] In a first aspect, the present application provides a component-based design method for an ultra-large span tunnel, comprising:

[0007] Obtaining parameter information of a super-long span tunnel, wherein the parameter information includes surrounding rock mechanical parameters, tunnel geometric parameters, and support material parameters;

[0008] Constructing a finite element model based on the parameter information, wherein the design parameters of the finite element model include anchor cable arrangement parameters for each excavation portion of the super-long span tunnel, wherein the anchor cable arrangement parameters include circumferential spacing, longitudinal spacing, and prestress of each anchor cable;

[0009] Set the excavation order of the excavation parts;

[0010] According to the excavation sequence and the finite element model, the anchor cable arrangement parameters of each excavation location are optimized to obtain the optimal design parameters.

[0011] In a second aspect, the present application also provides a device for designing a component-based ultra-large-span tunnel, comprising:

[0012] An acquisition module is used to obtain parameter information of a super-long span tunnel, wherein the parameter information includes surrounding rock mechanical parameters, tunnel geometric parameters and support material parameters;

[0013] A construction module is used to construct a finite element model based on the parameter information, wherein the design parameters of the finite element model include anchor cable arrangement parameters for each excavation portion of the super-long span tunnel, wherein the anchor cable arrangement parameters include circumferential spacing, longitudinal spacing, and prestress of each anchor cable;

[0014] Setting module, used to set the excavation order of excavation parts;

[0015] The optimization module is used to optimize the anchor cable arrangement parameters of each excavation site according to the excavation sequence and the finite element model to obtain the optimal design parameters.

[0016] Thirdly, the present application also provides a construction method for ultra-large span tunnel components, including:

[0017] Performing roof excavation and initial support for the ultra-large span tunnel, and tensioning anchor cables according to optimal design parameters, wherein the optimal design parameters are calculated according to the component-based design method for the ultra-large span tunnel;

[0018] Carry out side tunnel excavation and initial support on both sides of the super-large span tunnel, and tension the anchor cables according to the optimal design parameters;

[0019] Carry out layered excavation and initial support for super-large span tunnels, and reserve core soil;

[0020] Excavate core soil for ultra-large span tunnels and provide initial support;

[0021] The super-large span tunnel after excavation is subjected to secondary lining to obtain the construction result of the super-large span tunnel.

[0022] The beneficial effects of the present invention are as follows: the present invention realizes multi-objective optimization of anchor cable arrangement parameters at each excavation site by constructing a finite element model and combining it with a phased optimization strategy. Based on the response surface model and the non-dominated sorting genetic algorithm, it is possible to improve the rationality and economy of the design while ensuring the safety of the structure. By considering the coupling relationship between the excavation sequence and the structural response, the design process is more in line with the actual working conditions, and the response surface model greatly reduces the number of finite element analyses, improves the design efficiency, and has good engineering adaptability and promotion value. At the same time, the construction method of the present invention combines the optimal anchor cable design parameters, adopts measures such as pilot tunneling, anchor cable pre-support, core soil reservation and partial excavation, and realizes the safe, controllable and efficient forming of ultra-large span tunnels, thereby improving the construction quality and efficiency.

[0023] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or understood by practicing the embodiments of the present invention. The purposes and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 Schematic diagram of the design process of the componentized super-long-span tunnel according to an embodiment of the present invention;

[0026] Figure 2 Schematic diagram of the excavation location of the ultra-large span tunnel described in an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0028] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are used only to distinguish the description and should not be understood as indicating or implying relative importance.

[0029] Example 1:

[0030] This embodiment provides a design method for component-based ultra-long span tunnels.

[0031] See also Figure 1 , the figure shows that the method includes step S1, step S2, step S3 and step S4.

[0032] Step S1: Acquire parameter information of a super-long-span tunnel, wherein the parameter information includes surrounding rock mechanical parameters, tunnel geometric parameters, and support material parameters;

[0033] In this example, surrounding rock mechanical parameters include elastic modulus, Poisson's ratio, density, and shear strength parameters, representing surrounding rock deformation and stability. Tunnel geometric parameters include tunnel cross-sectional shape, span, height, and segmentation, forming the basis for model construction and segmented design. Support material parameters include the mechanical properties of shotcrete, steel arches, and anchor cables.

[0034] Step S2: constructing a finite element model based on the parameter information, wherein the design parameters of the finite element model include anchor cable arrangement parameters for each excavation portion of the super-long span tunnel, wherein the anchor cable arrangement parameters include circumferential spacing, longitudinal spacing, and prestress of each anchor cable;

[0035] In this embodiment, the prestress of each anchor cable is related to the circumferential spacing and the longitudinal spacing, and is related to different excavation locations. Specifically, the calculation formula for the prestress of each anchor cable is:

[0036] h a =k a 0.45 2 s-1 ·[1+i(d a1 -5)]

[0037]

[0038] Where h a represents the collapse height of excavation location a, k a represents the correction coefficient of the excavation location a, s represents the surrounding rock grade, and i represents d a1 The rate of increase or decrease of surrounding rock pressure per increase or decrease of 1m, d a1 represents the excavation span of excavation location a, d a2represents the longitudinal excavation cycle footage of the tunnel at excavation location a, ρ represents the surrounding rock density, g represents the acceleration of gravity, and F a represents the prestress of each anchor cable at excavation location a, s a1 Indicates the annular spacing of anchor cables at excavation location a, s a2 represents the longitudinal spacing of the anchor cables at excavation location a, where d a1 <5m, take i=0.2, when d a1 When ≥5m, take i=0.1.

[0039] In step S2, constructing a finite element model according to the parameter information includes:

[0040] Step S21: constructing a geometric model of the super-long-span tunnel using tunnel geometric parameters, wherein the geometric model includes multiple excavation locations;

[0041] Step S22: meshing the geometric model and assigning surrounding rock mechanical parameters to the geometric model;

[0042] In this embodiment, when dividing the grid, key parts (such as the vault and the haunch) are locally encrypted.

[0043] Step S23: obtaining support parameters and anchor material parameters according to support material parameters;

[0044] Step S24: Modeling the support structure according to the support parameters to obtain a support structure model, and modeling the anchor cable according to the anchor cable material parameters to obtain an anchor cable model;

[0045] Step S25: coupling the concrete model, the anchor cable model, and the geometric model to obtain a finite element model of support-surrounding rock-anchor cable;

[0046] Step S26: setting the boundary conditions and initial geostress field of the finite element model.

[0047] Step S3: setting the excavation order of the excavation parts;

[0048] In this embodiment, Figure 2 As shown, the excavation order is excavation part ①, excavation part ②, excavation part ③, excavation part ④, excavation part ⑤, excavation part ⑥, excavation part ⑦, excavation part ⑧, excavation part ⑨, excavation part ①0, excavation part Excavation site Excavation site Excavation site and excavation sites Among them, only the excavation parts ① to ⑦ need to be fixed with anchor cables. Therefore, the anchor cable arrangement parameters from excavation parts ① to ⑦ are designed according to the excavation sequence.

[0049] Step S4: Optimize the anchor cable arrangement parameters for each excavation location according to the excavation sequence and the finite element model to obtain the optimal design parameters.

[0050] The step S4 comprises:

[0051] Step S41: for each excavation location, performing excavation simulation on the current excavation location using the finite element model of the previous stage to obtain a first finite element model, wherein the finite element model of the previous stage includes the optimal anchor cable arrangement parameters of the previous excavation location;

[0052] In this example, tunnel design involves multiple complex factors (such as excavation sequence, anchor cable placement, and material strength), each of which influences the final result. By using phased optimization, the entire design process can be broken down into multiple smaller problems, each of which can be solved incrementally, simplifying the problem-solving process.

[0053] Tunnel excavation typically follows a specific sequence, and the design of each excavation section must consider the impact of preceding and following sections. Phased optimization aligns with the actual construction sequence, making the design more responsive to the needs of the actual construction process. During finite element analysis, the results of previous stages can be used to reduce the number of variables that need to be considered, avoiding the need to recalculate the responses of all excavation sections with each optimization.

[0054] Step S42: simulating excavation of the next excavation location using the first finite element model to obtain a response surface model of the current excavation location;

[0055] In step S42, obtaining the response surface model of the current excavation location includes:

[0056] Step S421: setting constraints on anchor cable arrangement parameters;

[0057] In this embodiment, the anchor cable arrangement parameter constraints are set with upper and lower limits based on design specifications, construction capabilities, and safety requirements. Stability constraints are also set, including structural performance constraints and construction physics constraints. Specifically, the structural performance constraints require that the maximum displacement and maximum principal stress be less than preset thresholds. Construction physics constraints include that the circumferential and longitudinal spacing of the anchor cables cannot be less than the minimum operating distance for anchor cable construction, and that the prestressing force cannot exceed the yield bearing capacity or anchoring force limit of the anchor cable material.

[0058] Step S422: setting a working condition design table according to the constraint conditions, wherein the working condition design table includes a plurality of anchor cable arrangement parameter combinations;

[0059] In this embodiment, the operating condition design table is generated through full factorial design or Latin hypercube sampling.

[0060] Step S423: adding support structures and anchor cables according to the working condition design table, updating the first finite element model, and obtaining a second finite element model under different anchor cable arrangement parameter combinations;

[0061] Step S424: Simulate excavation of the next excavation location using the second finite element model to obtain the structural response of the current excavation location under different anchor cable arrangement parameter combinations;

[0062] Step S425: Construct a response surface model using the structural response and operating condition design table.

[0063] The step S425 includes:

[0064] Step A1: Obtain the maximum principal stress and maximum displacement at key locations of the excavation site under different combinations of anchor cable arrangement parameters through structural response;

[0065] In this embodiment, a corresponding key position, such as the dome, is selected for each excavation location.

[0066] Step A2: Perform response surface fitting based on the maximum principal stress and maximum displacement to construct displacement polynomial function and stress polynomial function related to the anchor cable arrangement parameters;

[0067] In this embodiment, the circumferential spacing, longitudinal spacing and prestress of each anchor cable are used as independent variables, and two three-variable quadratic polynomial models are constructed to describe the relationship with stress and displacement respectively, wherein both quadratic polynomial models include coefficients to be fitted.

[0068] The coefficients to be fitted are calculated by the least square method to obtain the optimal polynomial coefficients, which are then substituted into the quadratic polynomial model to obtain the displacement polynomial function and the stress polynomial function.

[0069] Step A3: The displacement polynomial function and the stress polynomial function are used together as a response surface model.

[0070] In this embodiment, the response surface model obtained is specifically:

[0071] σ max =f1(s1,s2,F)

[0072] δ max =f2(s1,s2,F)

[0073] Where, σ max represents the maximum principal stress, δ max represents the maximum displacement, f1(·) represents the stress polynomial function, f2(·) represents the displacement polynomial function, s1 represents the circumferential spacing, s2 represents the longitudinal spacing, and F represents the prestress of each anchor cable.

[0074] Step S43: performing multi-objective optimization on the anchor cable arrangement parameters according to the response surface model to obtain the optimal anchor cable arrangement parameters for the current excavation location;

[0075] In step S43, obtaining the optimal anchor cable arrangement parameters for the current excavation location includes:

[0076] Step S431: Initializing a parent population, wherein the parent population includes a plurality of individuals, each of which is a combination of anchor cable arrangement parameters;

[0077] Step S432: Calculate the maximum displacement and maximum principal stress of each individual through the response surface model;

[0078] Step S433: Update the parent population using the maximum displacement and the maximum principal stress to obtain a joint population;

[0079] In step S433, obtaining the joint population includes:

[0080] Step B1: Perform non-dominated sorting on the parent population by maximum displacement and maximum principal stress to obtain individuals of multiple levels;

[0081] In this embodiment, individuals with better performance are ranked first, and if an individual is better than another individual in both objectives, it is considered to be better.

[0082] Step B2: Calculate the crowding degree for each level of individuals and construct a mating pool based on the crowding degree and the level of the individual;

[0083] In this embodiment, the crowding degree (i.e., the distance between individuals) is calculated for each level of individuals. This helps to avoid excessive aggregation during the selection process and maintain population diversity. Individuals with low crowding degrees indicate that there are many other individuals in the area, while individuals with high crowding degrees indicate that the area is sparsely populated. During the selection process, individuals with low crowding degrees are given priority in the mating pool.

[0084] Step B3: Construct a mating pool to perform crossover and mutation operations on individuals to obtain the offspring population;

[0085] Step B4: Merge the parent population and the child population to obtain a joint population.

[0086] Step S434: Determine whether the number of iterations has been reached. If so, select the individual with the highest level as the Pareto front solution set. Otherwise, use the joint population as the parent population for the next iteration and proceed to the next iteration.

[0087] Step S435: Select the optimal solution from the Pareto front solution set according to the actual project to obtain the optimal anchor cable arrangement parameters for the current excavation location.

[0088] In this embodiment, multiple design objectives are optimized simultaneously, namely, minimizing the maximum displacement and the maximum principal stress, to ensure that the anchor cable arrangement parameters are optimized in multiple aspects. Furthermore, through crossover and mutation in the genetic algorithm, local optimal solutions are avoided, and the potential design space can be effectively explored. Non-dominated sorting and crowding calculation are used to ensure the diversity of the population, and high-quality individuals can be preferentially selected to improve optimization efficiency.

[0089] Step S44: The optimal anchor cable arrangement parameters of all excavation locations are taken together as the optimal design parameters of the super-long span tunnel.

[0090] In summary, the design method of the present invention constructs a high-precision finite element model based on tunnel surrounding rock conditions, geometric parameters, and support material parameters. It then combines this with a phased optimization strategy to perform multi-objective optimization of anchor cable placement parameters at each excavation location. By constructing a response surface model and employing a non-dominated sorting genetic algorithm for parameter optimization, the scientific nature and engineering adaptability of anchor cable design are significantly improved, achieving a balance between structural safety and economic efficiency.

[0091] While ensuring constructibility, this design approach fully considers the impact of tunnel excavation sequence on structural response, ensuring that design decisions at each stage are more consistent with actual working conditions. Furthermore, the response surface model reduces finite element calculation costs, improves design efficiency, and effectively supports the rapid design and intelligent optimization of tunnel support systems, demonstrating strong engineering application value and intelligent capabilities.

[0092] Example 2:

[0093] This embodiment provides a design device for component-based ultra-long-span tunnels, the design device comprising:

[0094] An acquisition module is used to obtain parameter information of a super-long span tunnel, wherein the parameter information includes surrounding rock mechanical parameters, tunnel geometric parameters and support material parameters;

[0095] A construction module is used to construct a finite element model based on the parameter information, wherein the design parameters of the finite element model include anchor cable arrangement parameters for each excavation portion of the super-long span tunnel, wherein the anchor cable arrangement parameters include circumferential spacing, longitudinal spacing, and prestress of each anchor cable;

[0096] Setting module, used to set the excavation order of excavation parts;

[0097] The optimization module is used to optimize the anchor cable arrangement parameters of each excavation site according to the excavation sequence and the finite element model to obtain the optimal design parameters.

[0098] The optimization module includes:

[0099] a first simulation unit configured to perform excavation simulation on the current excavation location for each excavation location using a finite element model from a previous stage to obtain a first finite element model, wherein the finite element model from the previous stage includes optimal anchor cable arrangement parameters for the previous excavation location;

[0100] The second simulation unit is used to simulate the excavation of the next excavation part by using the first finite element model to obtain a response surface model of the current excavation part;

[0101] The optimization unit is used to perform multi-objective optimization on the anchor cable arrangement parameters according to the response surface model to obtain the optimal anchor cable arrangement parameters for the current excavation location;

[0102] The output unit is used to take the optimal anchor cable arrangement parameters of all excavation locations as the optimal design parameters of the super-long span tunnel.

[0103] It should be noted that, regarding the apparatus in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated on here.

[0104] Example 3:

[0105] This embodiment also provides a construction method for componentizing an ultra-large span tunnel, which includes step C1, step C2, step C3, step C4, and step C5.

[0106] Step C1: Excavate the top of the ultra-large-span tunnel and perform initial support, and tension the anchor cables according to the optimal design parameters calculated using the component-based design method for ultra-large-span tunnels;

[0107] In this embodiment, the top of the tunnel is excavated first. Specifically, a pilot tunnel is excavated first. After the pilot tunnel is penetrated, holes are drilled in the horizontal pilot tunnel according to the designed anchor hole positions, anchor cables are installed and grouting is carried out. After the strength of the anchor hole grouting body reaches the design requirements, tensioning operations are carried out.

[0108] The top hole of excavation section ① was excavated using weak blasting. The tunnel face was sealed with 5cm thick concrete spraying after each advance cycle. Initial support for the top hole of excavation section ① was implemented in stages, with an initial 5cm thick concrete spraying and the erection of a temporary vertical support steel frame. The arch of the top hole of excavation section ① was then sprayed with a second layer of concrete according to the designed thickness. Anchor cables were connected to the steel frame and tensioned to the designed prestressing force.

[0109] Similarly, after the top hole construction of Excavation Section ① is completed, Excavation Sections ② and ③ will be constructed using weak blasting, with Excavation Section ③ lagging behind Excavation Section ② by a certain distance. Initial support will be provided around Excavation Section ② in stages, with an initial 5cm thick concrete spraying and the erection of a temporary vertical support steel frame. The top hole arch of Excavation Section ② will be concreted a second time according to the design thickness. Anchor cables will be connected to the steel frame and tensioned to the designed prestressing force. The construction procedures and requirements for Excavation Section ③ are the same as for Excavation Section ②.

[0110] Step C2: Excavate the side tunnels and provide initial support for the super-long-span tunnel, and tension the anchor cables according to the optimal design parameters;

[0111] In this embodiment, after the top hole construction is completed, weak blasting is used to construct excavation areas ④ and ⑤, with excavation area ⑤ lagging behind excavation area ④ by a certain distance. Initial support for the top hole in excavation area ④ is performed in stages, with an initial 5 cm thick concrete spraying and the erection of a temporary vertical support steel frame. A second concrete spraying is performed on the top hole arch of excavation area ④ to the designed thickness. Anchor cables are connected to the steel frame and tensioned to the designed prestressing force.

[0112] The construction procedures and requirements for excavation part ⑤ are the same as those for excavation part ④.

[0113] Similarly, weak blasting is used to excavate areas ⑥ and ⑦, with excavation area ⑦ lagging behind excavation area ⑥ by a certain distance. The construction procedures and requirements for excavation areas ⑥ and ⑦ are the same as those for excavation area ④.

[0114] Excavation sites ⑧ and ⑨ were constructed using weak blasting, with excavation site ⑨ lagging behind excavation site ⑧ by a certain distance. Initial support for the top cavity of excavation site ⑧ was implemented in stages, with an initial 5cm thick spraying of concrete and the erection of a temporary vertical support steel frame. A second spraying of concrete was performed on the top cavity arch of excavation site ⑧ according to the designed thickness. The construction procedures and requirements for excavation site 9 were the same as for excavation site 8.

[0115] Similarly, weak blasting construction excavation area ①0 and excavation area Excavation site Lag behind the construction of part ①0 for a certain distance. The construction procedures and requirements are the same as those for the excavation area⑧.

[0116] Step C3: Carry out layered excavation and initial support for the super-large span tunnel, and reserve core soil;

[0117] In this embodiment, first remove the temporary support and then use weak blasting to excavate the site. and excavation sites Excavation site Delayed excavation area Construction is carried out at a certain distance. Excavation is carried out step by step. Initial support of the top hole is to spray 5cm thick concrete. The top arch of the cave is sprayed with concrete for the second time according to the design thickness requirements. The construction process and requirements are the same as those for the excavation site

[0118] Step C4: Excavate the core soil for the super-long span tunnel and carry out initial support;

[0119] In this embodiment, the delayed excavation area Excavation site A certain distance, weak blasting construction excavation area Excavation site Core soil, excavation area Delayed excavation area Construction is carried out at a certain distance. Excavation is carried out step by step. Initial support of the top hole is to spray 5cm thick concrete. The top arch of the cave is sprayed with concrete for the second time according to the design thickness requirements. The construction process and requirements are the same as those for the excavation site

[0120] Step C5: Perform secondary lining on the super-large span tunnel after excavation to obtain the construction result of the super-large span tunnel.

[0121] In this embodiment, the primary support concrete surface is processed according to the monitoring and measurement results, and the secondary lining is carried out using a lining formwork trolley.

[0122] The construction method proposed in this paper uses a pilot tunnel to determine geological conditions in advance, pre-anchoring the vault surrounding rock (critical surrounding rock) with anchor cables, and then reserving core soil to provide safety and a reinforcement platform. Using distributed excavation, the span of a single excavation is reduced, improving safety. The method is simple, requiring minimal process changes, and enables safe and rapid construction of ultra-large-span tunnels.

[0123] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

[0124] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A component-based design method for ultra-large span tunnels, characterized in that: include: Obtaining parameter information of a super-long span tunnel, wherein the parameter information includes surrounding rock mechanical parameters, tunnel geometric parameters, and support material parameters; Constructing a finite element model based on the parameter information, wherein the design parameters of the finite element model include anchor cable arrangement parameters for each excavation portion of the super-long span tunnel, wherein the anchor cable arrangement parameters include circumferential spacing, longitudinal spacing, and prestress of each anchor cable; Set the excavation order of the excavation parts; According to the excavation sequence and the finite element model, the anchor cable arrangement parameters of each excavation location are optimized to obtain the optimal design parameters.

2. The design method for ultra-large span tunnel components according to claim 1 is characterized in that ,The finite element model is constructed according to the parameter information, including: Constructing a geometric model of a super-long-span tunnel using tunnel geometric parameters, wherein the geometric model includes multiple excavation locations; Divide the geometric model into grids and assign the surrounding rock mechanical parameters to the geometric model; Obtain support parameters and anchor material parameters based on support material parameters; The support structure is modeled according to the support parameters to obtain a support structure model, and the anchor cable is modeled according to the anchor cable material parameters to obtain an anchor cable model; The concrete model, anchor cable model and geometric model are coupled to obtain the finite element model of support-surrounding rock-anchor cable; Set the boundary conditions and initial geostress field of the finite element model.

3. The design method for ultra-large span tunnel components according to claim 1 is characterized in that , the optimal design parameters are obtained, including: For each excavation location, performing excavation simulation on the current excavation location using the finite element model of the previous stage to obtain a first finite element model, wherein the finite element model of the previous stage includes the optimal anchor cable arrangement parameters of the previous excavation location; Simulating excavation of the next excavation site using the first finite element model to obtain a response surface model of the current excavation site; The anchor cable arrangement parameters are optimized by multi-objective method based on the response surface model to obtain the optimal anchor cable arrangement parameters for the current excavation location. The optimal anchor cable arrangement parameters of all excavation locations are taken together as the optimal design parameters of the super-long span tunnel.

4. The design method for ultra-large span tunnel components according to claim 3 is characterized in that , the response surface model of the current excavation location is obtained, including: Set constraints on anchor cable layout parameters; Setting a working condition design table according to the constraint conditions, wherein the working condition design table includes a plurality of anchor cable arrangement parameter combinations; Add support structures and anchor cables according to the working condition design table, update the first finite element model, and obtain the second finite element model under different anchor cable arrangement parameter combinations; The second finite element model is used to simulate the excavation of the next excavation site and obtain the structural response under different combinations of anchor cable arrangement parameters of the current excavation site; Response surface models are constructed using structural responses and load case design tables.

5. The design method for ultra-large span tunnel components according to claim 4 is characterized in that ,The response surface model is constructed through the structural response and working condition design table, including: The maximum principal stress and maximum displacement at key locations of the excavation site under different combinations of anchor cable arrangement parameters are obtained through structural response. Response surface fitting is performed based on the maximum principal stress and maximum displacement, and displacement polynomial function and stress polynomial function of anchor cable arrangement parameters are constructed. The displacement polynomial function and the stress polynomial function are used together as the response surface model.

6. The design method for ultra-large span tunnel components according to claim 5 is characterized in that , the optimal anchor cable arrangement parameters for the current excavation location are obtained, including: Initializing a parent population, wherein the parent population includes a plurality of individuals, each of which is a combination of anchor cable arrangement parameters; The maximum displacement and maximum principal stress of each individual were calculated using the response surface model; Update the parent population by the maximum displacement and maximum principal stress to obtain the joint population; Determine whether the number of iterations has been reached. If so, select the individual with the highest level as the Pareto front solution set. Otherwise, use the joint population as the parent population for the next iteration and proceed to the next iteration. According to the actual project, the optimal solution is selected from the Pareto front solution set to obtain the optimal anchor cable arrangement parameters for the current excavation location.

7. The design method for ultra-large span tunnel components according to claim 6 is characterized in that , the obtained joint population includes: The parent population is sorted non-dominated by the maximum displacement and the maximum principal stress to obtain individuals of multiple levels; The crowding degree is calculated for each rank of individuals, and a mating pool is constructed based on the crowding degree and the rank of the individuals; Construct a mating pool to perform crossover and mutation operations on individuals to obtain the offspring population; Merge the parent population and the offspring population to obtain the joint population.

8. A design device for component-based ultra-large-span tunnels, characterized in that: include: An acquisition module is used to obtain parameter information of a super-long span tunnel, wherein the parameter information includes surrounding rock mechanical parameters, tunnel geometric parameters and support material parameters; A construction module is used to construct a finite element model based on the parameter information, wherein the design parameters of the finite element model include anchor cable arrangement parameters for each excavation portion of the super-long span tunnel, wherein the anchor cable arrangement parameters include circumferential spacing, longitudinal spacing, and prestress of each anchor cable; Setting module, used to set the excavation order of excavation parts; The optimization module is used to optimize the anchor cable arrangement parameters of each excavation site according to the excavation sequence and the finite element model to obtain the optimal design parameters.

9. The design device for ultra-large-span tunnel components according to claim 8 is characterized in that , the optimization module includes: a first simulation unit configured to perform excavation simulation on the current excavation location for each excavation location using a finite element model from a previous stage to obtain a first finite element model, wherein the finite element model from the previous stage includes optimal anchor cable arrangement parameters for the previous excavation location; The second simulation unit is used to simulate the excavation of the next excavation part by using the first finite element model to obtain a response surface model of the current excavation part; The optimization unit is used to perform multi-objective optimization on the anchor cable arrangement parameters according to the response surface model to obtain the optimal anchor cable arrangement parameters for the current excavation location; The output unit is used to take the optimal anchor cable arrangement parameters of all excavation locations as the optimal design parameters of the super-long span tunnel.

10. A construction method for ultra-large span tunnel components, characterized in that: include: performing top excavation and initial support of the ultra-large-span tunnel, and tensioning anchor cables according to optimal design parameters, wherein the optimal design parameters are calculated according to the component-based design method for ultra-large-span tunnels according to any one of claims 1 to 7; Carry out side tunnel excavation and initial support on both sides of the super-large span tunnel, and tension the anchor cables according to the optimal design parameters; Carry out layered excavation and initial support for super-large span tunnels, and reserve core soil; Excavate core soil for ultra-large span tunnels and provide initial support; The super-large span tunnel after excavation is subjected to secondary lining to obtain the construction result of the super-large span tunnel.

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