A highway tunnel reinforcement bearing capacity calculation method based on rigidity analysis

Abstract

The application relates to a highway tunnel reinforcement bearing capacity calculation method based on stiffness analysis. The method collects real-time tunnel deformation of a to-be-detected highway tunnel, calculates corresponding bearing capacity reduction coefficients based on a function of the bearing capacity reduction coefficients and the tunnel deformation, and obtains the lining structure reinforcement bearing capacity based on the product of the bearing capacity reduction coefficients and the limit bearing capacity. The determination of the function of the bearing capacity reduction coefficients and the tunnel deformation comprises: performing indoor similar model test, calculating the prototype tunnel key point load value and the deformation value; establishing a two-dimensional finite element model of the prototype tunnel lining, performing stiffness inversion analysis, obtaining the relationship curve of the tunnel deformation and the stiffness reduction coefficient of the highway tunnel structure, establishing the corresponding relationship of the bearing capacity reduction coefficients and the tunnel deformation, and obtaining the function of the bearing capacity reduction coefficients and the tunnel deformation through function fitting. Compared with the prior art, the application has the advantages of high calculation efficiency and high calculation accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of highway tunnel structure safety, and particularly relates to a highway tunnel reinforcement bearing capacity calculation method based on stiffness analysis. BACKGROUND

[0002] After the completion of the highway tunnel, with the increase of service time, stratum change, construction quality and surrounding engineering activities, the tunnel structure performance will continuously deteriorate, and large deformation of the tunnel structure has become a common disease of highway tunnels.

[0003] In order to ensure the safety of the tunnel structure and maintain the normal operation of the tunnel, it is necessary to take effective reinforcement measures for the highway tunnel with abnormal deformation, and it is essential to calculate the bearing capacity of the tunnel structure before reinforcement, but the current highway tunnel reinforcement bearing capacity calculation methods, such as stratum structure method and load structure method, have some shortcomings such as complex calculation, less practicality, limited application range, etc. In actual reinforcement engineering, the calculation and analysis of highway tunnel reinforcement bearing capacity are often carried out through engineering experience or analogy. In order to improve the safety of the tunnel structure, there is still a lack of a method that can clearly calculate the highway tunnel reinforcement bearing capacity.

[0004] Patent application CN111101980A discloses a tunnel lining structure bearing capacity equivalent evaluation method. The method establishes an evaluation index system according to the degree, position and number of insufficient lining thickness, and uses the three expressions P' (i.e. evaluation bearing capacity) formed by the bearing capacity P (i.e. initial bearing capacity) of the tunnel lining structure in the initial state without damage, the influence index a of insufficient lining thickness and ring length, and the influence index b of the position of insufficient tunnel lining thickness on the bearing capacity as the bearing capacity of the tunnel structure after the insufficient lining thickness, so as to realize the bearing capacity evaluation under different tunnel engineering conditions. However, when this method is used for actual tunnel reinforcement bearing capacity calculation, there are problems such as inaccurate quantitative calculation of bearing capacity before reinforcement, limited actual application range, etc. Therefore, this method is not suitable for the calculation and analysis of highway tunnel reinforcement bearing capacity.

[0005] At present, the calculation and analysis of highway tunnel reinforcement bearing capacity are often carried out through engineering experience or analogy, and there is still a lack of a method that can clearly calculate the highway tunnel reinforcement bearing capacity, which cannot effectively calculate and analyze the bearing capacity of the highway tunnel before reinforcement, so as to ensure the safety of the tunnel structure and improve the service life of the tunnel. SUMMARY

[0006] The purpose of the present application is to overcome the defects of the prior art and provide a highway tunnel reinforcement bearing capacity calculation method based on stiffness analysis, which uses the function of the tunnel structure bearing capacity reduction coefficient and deformation to solve the problem of difficult accurate calculation of highway tunnel reinforcement bearing capacity, and has high calculation efficiency.

[0007] The purpose of the application can be realized by the following technical solutions:

[0008] A highway tunnel reinforcement bearing capacity calculation method based on stiffness analysis, the method comprises:

[0009] The real-time tunnel deformation of the to-be-detected highway tunnel is collected, the corresponding bearing capacity reduction coefficient is calculated based on a function of the bearing capacity reduction coefficient and the tunnel deformation, and the real-time lining structure reinforcement bearing capacity of the to-be-detected highway tunnel is calculated based on the product of the bearing capacity reduction coefficient and the ultimate bearing capacity.

[0010] The function of the bearing capacity reduction coefficient and the tunnel deformation is determined by the following steps:

[0011] An indoor similar model test is carried out based on the load-structure method, the relationship curve between the tunnel deformation and the load of the highway tunnel structure under an adverse load mode and the ultimate bearing capacity are obtained, a plurality of key points are set on the relationship curve, and the key point load value and the deformation value of the prototype tunnel are calculated according to the similarity ratio.

[0012] A two-dimensional finite element model of the prototype tunnel lining is established based on the load-structure method, the stiffness inversion analysis is carried out based on the key point load value and the deformation value, the stiffness reduction coefficient of the lining structure is calculated, and the relationship curve between the tunnel deformation and the stiffness reduction coefficient of the highway tunnel structure under the adverse load mode is obtained.

[0013] The relationship curve between the tunnel deformation and the stiffness reduction coefficient of the highway tunnel structure is divided into a plurality of damage states, the tunnel deformation range under each damage state is recorded, the corresponding relationship between the bearing capacity reduction coefficient and the tunnel deformation is established according to the bearing capacity reduction coefficients under different damage states recorded in the industry specification, and the function of the bearing capacity reduction coefficient and the tunnel deformation of the prototype tunnel is obtained through function fitting.

[0014] Further, the tunnel deformation includes the horizontal displacement of the side wall and / or the vertical displacement of the vault.

[0015] Further, the function of the bearing capacity reduction coefficient and the tunnel deformation includes a first function of the bearing capacity reduction coefficient and the horizontal displacement of the side wall and a second function of the bearing capacity reduction coefficient and the vertical displacement of the vault, and when calculating the real-time lining structure reinforcement bearing capacity of the to-be-detected highway tunnel, the smaller bearing capacity reduction coefficient obtained based on the first function and the second function is used for calculation.

[0016] Further, the indoor similar model test is specifically:

[0017] Based on the similar ratio, a highway tunnel lining model is obtained, under the selected adverse load mode, a full-circle loading device is used to load the highway tunnel lining model, the stress deformation characteristics, failure mode and damage process of the tunnel structure under the adverse load are analyzed, the relationship curve of deformation and load is recorded, and the ultimate bearing capacity is recorded.

[0018] Further, when performing the stiffness inversion analysis, the effective thickness of the lining section is taken as the inversion parameter.

[0019] Further, when performing the stiffness inversion analysis, the effective thickness of the lining section is adjusted under each key point load value, so that the calculated displacement is consistent with the deformation value of the prototype tunnel key point, and the structure stiffness under each load state is inversely deduced, and the corresponding stiffness reduction coefficient is calculated, and the calculation formula is:

[0020]

[0021] Wherein, alpha is the stiffness reduction coefficient, h is the effective thickness of the lining section under a certain load state, h0 is the initial thickness of the lining calculation section.

[0022] Further, the adverse load mode includes lateral load and / or vertical overload.

[0023] Further, after setting a plurality of key points, the relationship curve between the tunnel deformation and the load is divided into an elastic stress stage of the structure under the design load, a structure haunch cracking stage, a structure protection layer local crushing and peeling stage and a structure softening and damage stage.

[0024] Further, the damage state includes a basic undamaged stage, a structure slightly damaged stage, a structure damage aggravated stage, a structure softening stage and a structure residual stiffness stage.

[0025] Further, the function expression of the bearing capacity reduction coefficient of the prototype tunnel and the tunnel deformation is:

[0026]

[0027] Wherein, alpha is the stiffness reduction coefficient, h is the effective thickness of the lining section under a certain load state, h0 is the initial thickness of the lining calculation section. r The bearing capacity reduction coefficient is a function of the tunnel deformation of the prototype tunnel, and a, b and k are function parameters obtained by fitting the function.

[0028] Compared with the prior art, the present application has the following beneficial effects:

[0029] 1. Based on the stiffness equivalence, the stiffness reduction coefficient is used to analyze the reinforcement bearing capacity of the highway tunnel, which solves the problem that the traditional specification table cannot be applied to the reinforcement bearing capacity reduction, and the calculation efficiency is high.

[0030] 2、The present application takes the easily measured tunnel deformation as a parameter to calculate the reinforcement bearing capacity of the tunnel, and the calculation result is accurate and reliable, and can be directly applied to practical engineering, and has wide application range.

[0031] 3、The present application realizes the quantitative analysis of the reinforcement bearing capacity of the highway tunnel by establishing the fitting curve formula of the displacement and bearing capacity reduction coefficient of the side wall and the vault of the tunnel lining structure, and provides a new and more accurate method for the calculation and analysis of the reinforcement bearing capacity of the highway tunnel. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 The function acquisition flowchart of the present application is shown in the figure;

[0033] Figure 2 The structure size schematic diagram of the highway tunnel needing to be calculated is shown in the figure;

[0034] Figure 3 The lateral load mode schematic diagram is shown in the figure;

[0035] Figure 4 The relationship curve between the side wall displacement and the load of the highway tunnel structure under the lateral load mode is shown in the figure;

[0036] Figure 5 The relationship curve between the vault displacement and the load of the highway tunnel structure under the lateral load mode is shown in the figure;

[0037] Figure 6 The two-dimensional finite element calculation model schematic diagram of the prototype tunnel lining is shown in the figure;

[0038] Figure 7 The relationship curve between the side wall displacement of the highway tunnel structure and the lining structure stiffness reduction coefficient α under the lateral load is shown in the figure;

[0039] Figure 8 The relationship curve between the vault displacement of the highway tunnel structure and the lining structure stiffness reduction coefficient α under the lateral load is shown in the figure. DETAILED DESCRIPTION

[0040] The present application will be described in detail below in combination with the drawings and specific embodiments. The present embodiment is implemented on the premise of the technical scheme of the present application, and detailed implementation mode and specific operation process are given, but the protection scope of the present application is not limited to the following embodiments.

[0041] TERMS EXPLANATION

[0042] Ultimate bearing capacity F: the maximum jacking force of the loading area jack when the model loses the bearing capacity.

[0043] Stiffness equivalent: the lining in simulation has no cracking property, the lining thickness of the model is adjusted constantly to ensure the same deformation of simulation and test (the lining has cracking property), so as to obtain the structural stiffness EI of the prototype lining under different deformations.

[0044] Section effective thickness h: under the action of adverse load, the section part of the lining has failed and has no contribution to the stiffness of the lining, and the section effective thickness h is the initial thickness h0 of the lining section minus the height of the failed part.

[0045] Lining bearing capacity reduction coefficient α r : when the bearing capacity of the tunnel lining structure is reduced due to diseases and needs to be reinforced, the bearing capacity of the lining structure is reduced according to the lining damage technical condition value.

[0046] Lining stiffness reduction coefficient α: the ratio of the structural stiffness EI to the initial stiffness EI0 of the prototype tunnel.

[0047] The application provides a highway tunnel reinforcement bearing capacity calculation method based on stiffness analysis, which comprises the following steps: collecting real-time tunnel deformation of a to-be-detected highway tunnel, calculating a corresponding bearing capacity reduction coefficient based on a function of a predetermined bearing capacity reduction coefficient and tunnel deformation, and calculating a real-time lining structure reinforcement bearing capacity of the to-be-detected highway tunnel based on the product of the bearing capacity reduction coefficient and a limit bearing capacity, i.e. r F r = α r × F, α r is the bearing capacity reduction coefficient, and F is the limit bearing capacity.

[0048] The above method uses the function of the tunnel structure bearing capacity reduction coefficient and deformation to solve the problem that the highway tunnel reinforcement bearing capacity is difficult to accurately calculate.

[0049] Reference Figure 1 In the above method, the determination process of the function of the bearing capacity reduction coefficient and the tunnel deformation comprises the following steps:

[0050] S1, indoor similar model test is carried out based on the load-structure method, the relationship curve between the tunnel deformation and the load of the highway tunnel structure under the adverse load mode and the limit bearing capacity are obtained, and a plurality of key points are set on the relationship curve, and the key point load value and deformation value of the prototype tunnel are calculated according to the similarity ratio.

[0051] In the specific embodiment, the tunnel deformation includes the horizontal displacement of the side wall, the vertical displacement of the vault and the like. The indoor similar model test specifically comprises:

[0052] A highway tunnel lining model is obtained based on a similarity ratio, a full-circle loading device is used to load the lining model under a selected adverse load mode, stress and deformation characteristics, failure mode and damage process of the tunnel structure under the adverse load are analyzed, a relationship curve between lining structure deformation and load is recorded, and ultimate bearing capacity is obtained. The lining structure deformation includes horizontal displacement of the side wall and vertical displacement of the vault. During the test, the similarity ratio can be selected according to actual needs.

[0053] The adverse load mode includes lateral load and vertical overload, wherein the lateral load is mainly lateral pressure when the tunnel passes through an expansive surrounding rock, argillaceous schist and other unfavorable geological sections, and the plastic pressure becomes the main load acting on the tunnel lining under the condition that the surrounding rock strength is significantly smaller than the soil pressure or the surrounding rock strength degrades. The vertical overload is that the ground stacking load and other adverse factors make the vertical pressure of the surrounding rock acting on the tunnel lining larger.

[0054] In the specific embodiment, after a plurality of key points are set, the relationship curve is divided into a plurality of stages, including:

[0055] ① The design load loading point to the first cracking point of the structure is divided into the elastic stress stage of the structure;

[0056] ② The first cracking point of the structure to the first yield point is divided into the arch waist cracking stage of the structure, and the first yield point of the structure is that the concrete protective layer reaches its tensile strength and breaks;

[0057] ③ The first yield point of the structure to the limit state point is divided into the local broken and peeled stage of the structure protective layer, and the limit state point of the structure is that the structure appears shear failure;

[0058] ④ The limit state point of the structure to the collapse point is divided into the softening damage stage of the structure, and the collapse point of the structure is that the structure has excessive deformation and bending failure.

[0059] S2, a two-dimensional finite element model of the prototype tunnel lining is established based on the load-structure method, stiffness inversion analysis is performed based on the key point load value and deformation value, the stiffness reduction coefficient of the lining structure is calculated and obtained, and the relationship curve between the tunnel deformation of the highway tunnel structure and the stiffness reduction coefficient under the adverse load mode is obtained.

[0060] In the specific embodiment, when performing the stiffness inversion analysis, the effective thickness h of the lining section is taken as the inversion parameter, because the lining in the model does not have cracking properties, the lining thickness is continuously adjusted to ensure that the simulation and the test (the lining has cracking properties) have the same deformation, so as to obtain the structural stiffness EI of the prototype lining under different deformations. The effective thickness h of the section is the part of the section that has failed under the adverse load of the lining, which does not contribute to the stiffness of the lining. The effective thickness h of the section is the initial thickness h0 of the lining section minus the height of the failed part.

[0061] In the specific embodiment, the stiffness inversion analysis specifically comprises:

[0062] (1) Calculate the key point displacement under each load level, and based on the stiffness equivalence principle, adjust the effective thickness h of the section to weaken the section stiffness EI, so that the calculated displacement is consistent with the key point displacement of the prototype tunnel, so as to inversely deduce the structural stiffness EI under the displacement state of each load level;

[0063] (2) Calculate the lining structure stiffness reduction coefficient a:

[0064]

[0065] In the formula, E is the elastic modulus of the prototype tunnel lining; I is the inertia moment of the lining calculation section under a certain load-displacement level; I0 is the initial inertia moment of the lining calculation section; h is the effective thickness of the lining calculation section under a certain load-displacement level; h0 is the initial thickness of the lining calculation section;

[0066] (3) Based on the inversion analysis of the structural stiffness EI, the relationship curve between the displacement of the highway tunnel structure side wall and vault and the lining structure stiffness reduction coefficient a under the adverse load mode is obtained.

[0067] S3, divide the relationship curve between the tunnel deformation of the highway tunnel structure and the stiffness reduction coefficient a into several damage states, record the tunnel deformation range under each damage state, and establish the corresponding relationship between the bearing capacity reduction coefficient and the tunnel deformation according to the bearing capacity reduction coefficient under different damage states recorded in the industry standard, and obtain the function of the bearing capacity reduction coefficient and the tunnel deformation of the prototype tunnel through function fitting.

[0068] In the specific embodiment, the several damage states divided can include a structure basically undamaged stage, a structure slightly damaged stage, a structure damage aggravated stage, a structure softened stage, and a structure residual stiffness stage.

[0069] Lining bearing capacity reduction coefficient a r When the bearing capacity of the tunnel lining structure is reduced due to diseases and needs to be reinforced, the bearing capacity of the lining structure is calculated according to the lining damage technical condition value, and the reduction coefficient when the reduction coefficient is reduced.

[0070] In the specific embodiment, the lining bearing capacity reduction coefficient a r The fitting function of the tunnel deformation is specifically:

[0071]

[0072] In the formula, x is the displacement (cm) of the lining side wall or vault of the prototype tunnel; a, b, and k are function parameters.

[0073] If the above method is realized in the form of a software function unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the parts that contribute to the prior art or parts of the technical solutions can be embodied in the form of a software product, which is stored in a storage medium and includes instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0074] The above method is described in a specific embodiment.

[0075] I. Based on the similar model test of the highway tunnel structure (the size of the tunnel structure is shown in Figure 2 ), the relationship curves between the displacement of the side wall and the load and the ultimate bearing capacity F under the lateral load mode (see Figure 3 ) are obtained, which are respectively the first and second relationship curves, as shown in Figure 4 、 Figure 5 According to the failure process, strain development and deformation law of the lining, the stress and deformation process of the lining is divided into four stages, which are respectively the elastic stress stage of the structure under the design load, the structure haunch cracking stage, the structure protection layer local broken peeling stage, and the structure softening failure stage. Each key point corresponds to the threshold value of the side wall horizontal or arch top vertical displacement under the current load.

[0076] II. According to the first and second relationship curves, the key point load value and displacement of the prototype tunnel are obtained through the similarity ratio 1:10 conversion, and the key point displacement is the side wall horizontal and arch top vertical displacement:

[0077] The load value of each point of the prototype tunnel = the load value of each point of the model test × 10

[0078] The key point displacement of the prototype tunnel = the key point displacement of the model test × 10

[0079] III. Based on the model test data, a two-dimensional finite element calculation model of the prototype tunnel lining is established by using the finite element numerical analysis software through the load structure method, as shown in Figure 6 , and the inverse analysis of the structure stiffness EI is carried out, and the effective thickness h of the lining section is taken as the inverse parameter.

[0080] Four, calculate the displacement of the key point under each level of load, and adjust the effective thickness h of the section based on the stiffness equivalence principle to weaken the section stiffness EI, so that the calculated displacement is consistent with the displacement of the key point of the prototype tunnel, and the structural stiffness EI under each level of load displacement state is inversely deduced.

[0081] Five, calculate the reduction coefficient a of the lining structure stiffness:

[0082]

[0083] In the formula, E is the elastic modulus of the prototype tunnel lining; I is the inertia moment of the calculation section of the lining under a certain level of load-displacement; I0 is the initial inertia moment of the calculation section of the lining; h is the effective thickness of the calculation section of the lining under a certain level of load-displacement; h0 is the initial thickness of the calculation section of the lining.

[0084] Six, according to the inverse analysis of the structural stiffness EI, the relationship curve between the displacement of the side wall and the vault of the highway tunnel structure under lateral load and the reduction coefficient a of the lining structure stiffness is obtained, which is respectively the third and fourth relationship curves, see Figure 7 、 Figure 8 .

[0085] Seven, according to the five key nodes of the tunnel lining structure entering the slight damage state, the damage intensification state, the softening state, the residual stiffness state and the structure losing bearing capacity in the model test, the stiffness attenuation process of the lining structure is divided into five stages, which are [1, 0.95], (0.95, 0.57], (0.57, 0.33], (0.33, 0.21], (0.21, 0.16].

[0086] Eight, the five stages of the lining structure stiffness attenuation are respectively corresponding to the five technical state values of the civil structure in the “Technical Code for Maintenance of Highway Tunnels (JTG H12-2015)” (see Table 1), and the corresponding displacement ranges of the side wall and the vault are obtained according to the 1-5 stages divided by the third and fourth relationship curves, as shown in Table 2.

[0087] Table 1 Evaluation criteria for technical state of civil structure

[0088]

[0089] Table 2 Relationship between lining structure damage state and displacement of side wall and vault

[0090]

[0091] Nine, according to the bearing capacity reduction coefficient a corresponding to the technical state value of the tunnel lining structure being 1-5 in the “Technical Code for Reinforcement of Highway Tunnels (JTG / T 5540-2018)” (see Table 3), the bearing capacity reduction coefficient a of the lining structure under different damage states is established. r Table 3 Bearing capacity reduction coefficient a corresponding to technical state value of tunnel lining structurer The relationship between the side wall displacement and the vault displacement is shown in Table 4, and the tunnel original structure bearing capacity reduction factor a is obtained by function fitting r The function of the tunnel deformation is:

[0092] COD(R 2 ) = 0.98

[0093] COD(R 2 ) = 0.98

[0094] In the formula, x1 and x2 are the original tunnel lining side wall convergence and vault heave displacement (cm) respectively.

[0095] Table 3 Lining bearing capacity reduction factor a r

[0096]

[0097]

[0098] Table 4 Lining bearing capacity reduction factor a r The relationship between the tunnel deformation and the vault displacement

[0099]

[0100] Ten, if the current tunnel lining side wall convergence displacement is x1 cm, then the lining structure reinforcement bearing capacity F r is:

[0101]

[0102] If the current tunnel lining vault heave displacement is x2 cm, then the lining structure reinforcement bearing capacity F r is:

[0103]

[0104] In the formula, x1 and x2 are the original tunnel lining side wall convergence and vault heave displacement (cm) respectively; a r is the lining bearing capacity reduction factor; F is the lining structure ultimate bearing capacity (N);

[0105] Tunnel lining reinforcement bearing capacity F r Take the minimum value of the above calculation results.

[0106] The preferred embodiments of the present application have been described above in detail. It should be understood that modifications and variations to the preferred embodiments could be made by those skilled in the art in light of the teachings above without departing from the spirit of the present application. It is therefore to be understood that what is desired to be protected by letters patent is defined by the scope of the claims that follow and that on behalf of which the summary of the application is intended to serve.

Claims

1. A highway tunnel reinforcement bearing capacity calculation method based on stiffness analysis, characterized in that, The method comprises: The method comprises: The method comprises: The function of the bearing capacity reduction coefficient and the tunnel deformation is determined through the following steps: An indoor similar model test is performed based on the load-structure method to obtain a relationship curve between the tunnel deformation and the load and a limit bearing capacity of the highway tunnel structure under an adverse load mode, a plurality of key points are set on the relationship curve, and a prototype tunnel key point load value and a deformation value are calculated according to a similarity ratio; A two-dimensional finite element model of the prototype tunnel lining is established based on the load-structure method, a stiffness inversion analysis is performed based on the key point load value and the deformation value, a stiffness reduction coefficient of the lining structure is calculated, and a relationship curve between the tunnel deformation and the stiffness reduction coefficient of the highway tunnel structure under the adverse load mode is obtained; 2. The method for calculating the carrying capacity of a highway tunnel reinforcement based on rigidity analysis according to claim 1, characterized in that, The relationship curve between the tunnel deformation and the stiffness reduction coefficient of the highway tunnel structure is divided into a plurality of damage states, a tunnel deformation range under each damage state is recorded, a corresponding relationship between the bearing capacity reduction coefficient and the tunnel deformation is established according to bearing capacity reduction coefficients of different damage states recorded according to an industry specification, a function of the bearing capacity reduction coefficient and the tunnel deformation of the prototype tunnel is obtained through function fitting.

3. The method for calculating the carrying capacity of a highway tunnel reinforcement based on rigidity analysis according to claim 1, characterized in that, The tunnel deformation comprises a sidewall horizontal displacement and / or a vault vertical displacement.

4. The method for calculating the carrying capacity of a highway tunnel reinforcement based on rigidity analysis according to claim 1, characterized in that, The function of the bearing capacity reduction coefficient and the tunnel deformation comprises a first function of the bearing capacity reduction coefficient and the sidewall horizontal displacement and a second function of the bearing capacity reduction coefficient and the vault vertical displacement, and a smaller bearing capacity reduction coefficient obtained based on the first function and the second function is used for calculation when the real-time lining structure reinforcement bearing capacity of the highway tunnel to be detected is calculated. The indoor similar model test is specifically performed as follows:

5. The method for calculating the carrying capacity of a highway tunnel reinforcement based on rigidity analysis according to claim 1, characterized in that, A highway tunnel lining model is obtained based on a similarity ratio, a full-circumference loading device is used to load the highway tunnel lining model under a selected adverse load mode, stress and deformation characteristics, a failure mode and a damage process of the tunnel structure under the adverse load are analyzed, a relationship curve between the deformation and the load is recorded, and a limit bearing capacity is recorded.

6. The method for calculating the carrying capacity of a highway tunnel reinforcement based on rigidity analysis according to claim 5, characterized in that, The lining section effective thickness is used as a parameter to be inverted when the stiffness inversion analysis is performed. The lining section effective thickness is adjusted at each key point load value so that the calculated displacement is consistent with the prototype tunnel key point deformation value, the structure stiffness under each load state is inversely deduced, and the corresponding stiffness reduction coefficient is calculated, and the calculation formula is as follows:

7. The method for calculating the carrying capacity of a highway tunnel reinforcement based on rigidity analysis according to claim 1, characterized in that, The adverse load mode comprises a lateral load and / or a vertical overload.

8. The method for calculating the carrying capacity of a highway tunnel reinforcement based on rigidity analysis according to claim 1, characterized in that, After the plurality of key points are set, the relationship curve between the tunnel deformation and the load is divided into an elastic stress stage of the structure under a design load, a structure haunch cracking stage, a structure protection layer local crushing and peeling stage, and a structure softening and failure stage. 9.The method of claim 1, wherein, The damage state includes a substantially undamaged stage, a structure slightly damaged stage, a structure damage aggravated stage, a structure softened stage and a structure residual stiffness stage.

10. The method for calculating the carrying capacity of a highway tunnel reinforcement based on rigidity analysis according to claim 1, characterized in that, The function of the bearing capacity reduction factor of the prototype tunnel and the tunnel deformation is expressed as: wherein a r is a bearing capacity reduction coefficient, x is the tunnel deformation of the prototype tunnel, and a, b, and k are function parameters obtained by fitting the function.

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