46 results about "Bond slip" patented technology

The invention discloses a method for calculating the flexural capacity of a prefabricated segmental girder bridge based on steel shear keys, and belongs to the technical field of fabricated prefabricated segmental girder bridges. According to the method, on the basis of the concrete plasticity theory, a theoretical stress model of bending plastic deformation of the prefabricated segmental girder bridge is constructed, a cracking bending moment calculation formula of the three-section type prefabricated segmental girder bridge is established, and design refinement and design efficiency are improved; based on the fact that the anti-bending bearing capacity of the joint of the segmental beam is mainly determined by deformation of a pressed area of a concrete top plate and limit stress of a steel strand, a calculation formula of the anti-bending bearing capacity of the three-section type prefabricated segmental beam bridge at the joint and the non-joint is provided; according to the method, the plastic deformation of the concrete and the bonding slippage effect of the reinforcing steel bars are considered, the bending bearing capacity of the three-section type prefabricated segmental girder bridge can be accurately calculated, and the calculation method is verified to be safe and reliable through comparison with an experimental value.

This invention discloses a method and system for numerically defining a rebar-concrete interface element under both monotonic and cyclic loading, comprising: first, establishing a finite element model of reinforced concrete component, and generating a solver input file within the finite element software; then, adding a series of user-defined interface elements in the solver input file; then, inputting parameters of characteristic points of the axial bond-slip curve between rebar and concrete, the diameter of rebar, and the characteristic parameters of fibers associated with the user-defined element (UEL) in the solver input file; then, setting the element stiffness matrix, the coordinate transformation matrix and residual in the UEL subroutine; finally, submitting the solver input file in the finite element software, and calling the UEL subroutine for calculation.

The invention discloses a thermal-mechanical coupling behavior numerical simulation system for a reinforced concrete structure, and particularly relates to the field of constructional engineering, and the system comprises a heat conduction analysis module, a mechanical behavior analysis module, a bond slip behavior analysis module and a simulation calibration module. The heat conduction analysis module simulates the temperature field change of the concrete in the fire disaster process by defining temperature related parameters of the concrete; the mechanical behavior analysis module is used for simulating nonlinear mechanical behaviors of concrete and analyzing strength degradation, crack propagation and plastic deformation of the concrete at high temperature in combination with a temperature-dependent material model; and the bond slip behavior analysis module is used for setting a non-linear contact behavior between the reinforcing steel bar and the concrete. According to the invention, comprehensive simulation of reinforced concrete under high-temperature conditions such as fire disasters and the like is realized, and the strength degradation and crack propagation of the concrete and the bond slip behavior of the reinforcing steel bars and the concrete can be accurately predicted in combination with a temperature field and a mechanical field.

The invention relates to the field of building materials and structural engineering, in particular to an analysis method of a composite interface cohesive mechanical behavior. The method for analyzing the cohesive mechanical behavior of the composite interface comprises the following steps: forming the composite interface; respectively applying a tensile load and an alternating electric field in the axial direction and the transverse direction of the modified carbon fiber; establishing a trilinear bond slip constitutive model; measuring an interface impedance phase angle in real time, and calculating an interface damage index; and correcting the trilinear bond slip constitutive model by using the damage index, and analyzing the composite interface cohesive mechanical behavior. According to the method, the nano SiO2 is successfully deposited on the surface of the carbon fiber, synchronous acquisition of interface slippage, strain and impedance spectrum under multi-coupling stress is also realized, and a synergistic effect mechanism of multiple fields to interface damage is conveniently disclosed.

The present invention relates to a method for calculating the interfacial bond slip of rebar-anchored concrete components under cyclic loads, and belongs to the technical field of engineering structure reinforcement and reconstruction. The method comprises three parts, namely, analysis of rebar bond stress, correction of bond slip calculation under static loads, and calculation of bond slip under cyclic loads. The present invention takes into account the influence of the main factors of rebar bonding, such as the rebar diameter and the rebar anchoring depth, and accurately describes the influence of the key factors affecting the pull-out bearing capacity of rebar-anchored components, such as the rebar diameter and the rebar anchoring depth, on the bond force, thereby providing a theoretical basis for calculating the internal force and deformation of rebar-anchored components and improving the design of rebar reinforcement and reconstruction projects.

This invention relates to a method for establishing a constitutive model of localized bond in ultra-high performance concrete (UHPC) structures and its finite element method implementation. Firstly, based on the energy release rate per unit crack surface, a coarse aggregate-fiber competitive fracture index is proposed. Based on this, a multi-field coupled effective fiber weighting function is constructed, explicitly incorporating factors such as coarse aggregate volume fraction, particle size, tensile strength, fiber content, bond length ratio, and cover thickness ratio. Furthermore, an internal state variable representing the degree of coarse aggregate participation is introduced within a four-stage bond-slip framework, expressing the bond stress as a superposition of three parts: matrix, fiber bridging, and coarse aggregate-rib mechanical interlocking. A dedicated UHPC-CA-reinforcement interface element and numerical implementation scheme are designed, which can improve the accuracy and engineering usability of the analysis of anchorage and lap zone in UHPC containing coarse aggregate.

The invention discloses a concrete member simulation model building method based on a BIM technology, and relates to the technical field of concrete member BIM simulation, and the method comprises the steps: obtaining design information including the geometric dimension definition of a member, a steel bar arrangement detail drawing, a concrete strength grade requirement and an external load action parameter; the method comprises the following steps: establishing a parameterized three-dimensional geometry on a BIM platform, associating strength requirements, implanting a parameterized reinforcement network model containing spatial trend, diameter, protective layer thickness and bond-slip relationship according to a reinforcement detail drawing, integrating to generate a preliminary BIM integrated model, calling a structure analysis engine to execute static and dynamic coupling numerical analysis by taking the model, strength and load as input, and establishing a structural analysis model; and generating a multi-working-condition mechanical response data set. According to the method, through reinforcement bond-slip relation definition and BIM model direct-connection static and dynamic coupling analysis, the integrity of concrete member simulation modeling and mechanical analysis is improved, and modeling and analysis integrated connection is achieved.

The invention belongs to the technical field of rock soil and structural engineering, and discloses an anchor rod bearing performance prediction method and related device based on data driving and physical constraint, and the method comprises the steps: obtaining a short anchor test curve of a to-be-tested anchor rod; based on the short anchor test curve of the to-be-tested anchor rod, and in combination with a pre-constructed bond-slip model parameter identification model, obtaining multi-stage parameters of the bond-slip model; the pre-constructed bonding-slippage model parameter identification model is a decision tree model in which preset mathematical physical constraints are introduced; substituting the multi-stage parameters of the bond-slip model into the four-linear bond-slip control equation to generate a load-slip curve of the to-be-tested anchor rod; according to the load-slip curve of the to-be-tested anchor rod, obtaining a preset bearing performance index of the to-be-tested anchor rod, and taking the preset bearing performance index as a bearing performance prediction result of the to-be-tested anchor rod; according to the method, the test cost is greatly reduced, the prediction effect is improved, high universality can be kept, and a reliable basis is provided for design and optimization of the anchor rod.

The invention provides a finite element calculation method for beam moving construction stress of a widening pier of a railway pier. The finite element calculation method comprises the following steps: establishing a three-dimensional model, and performing grid division and refinement; constructing a concrete constitutive model; obtaining a bonding-slip curve of a bonding surface similar to the actual working condition; obtaining soil layer data in a construction range of new and old piers and settlement data of the old piers, and calculating a settlement difference value of the new and old piers in beam moving construction; inputting the obtained parameters into a finite element model for fitting to obtain a concrete plastic damage model CDP and a bonding surface model; defining settlement data to boundary conditions of the bottom of the three-dimensional model of the new and old piers; the method comprises the following steps: simulating top stress change generated in a beam moving process applied to the tops of new and old piers, obtaining a stress distribution cloud chart of the interiors of the new and old piers and a bonding surface through numerical simulation, and comparing a simulation result with parameters obtained by a new and old concrete bonding surface shear failure test and a theoretical calculation value of a local pressure-bearing model; and verifying the accuracy of a stress distribution result and a bonding surface damage result.

The invention discloses a reinforced concrete pull-out test device. The reinforced concrete pull-out test device comprises a device main body, a concrete test piece clamping device, a loading device and a displacement meter fixing device, the clamping device is composed of an upper clamping plate, a lower clamping plate, an upper rotating arm and a lower rotating arm, the upper rotating arm and the lower rotating arm are connected with a common rotating arm rotating shaft, the upper clamping plate and the lower clamping plate are in a step shape, compliance layers are attached to the contact faces, and the rotating arms can independently rotate and be locked so as to adapt to the uneven surface of a test piece, and clamping lateral pressure is reduced. The loading device is composed of a loading plate, a supporting plate and paired symmetrical connecting rod pieces, opposite adjusting nuts on the connecting rod pieces are used for synchronously adjusting the inclination angle of the supporting plate, and a self-centering pair is arranged between the loading plate and the supporting plate, so that loading force is transmitted in the axis direction of the steel bar. The device effectively improves the accuracy and repeatability of the bonding-slipping test, and is suitable for scientific research and engineering detection.

The invention provides a construction method of a geopolymer coating bond-slip constitutive model, and relates to the technical field of concrete bond-slip constitutive research, and the construction method comprises the following steps: carrying out a center pull-out test on a geopolymer coating steel bar pouring concrete test piece to obtain loading end slip, free end slip and bond stress data; calculating the relative slip and the average bonding stress, analyzing the relative slip and the average bonding stress to obtain the relation between the relative slip length and the average bonding stress, and correcting the relation between the relative slip length and the average bonding stress through the geopolymer influence coefficient; the bonding stress data are analyzed, and the relation between the relative anchoring position and the relative bonding stress is obtained; according to the corrected relation between the relative slip length and the average bonding stress and the relation between the relative anchoring position and the relative bonding stress, the geopolymer coating bonding slip constitutive relation is constructed, and the geopolymer coating bonding slip constitutive relation is corrected based on complex network entropy flow logic.

The application discloses a built-in magnetic three-dimensional bond-slip testing device and a mounting testing method thereof, which is used for testing the bond-slip and vertical peeling at the interface of a steel plate-concrete composite structure, is mounted on the inner side of the steel plate before pouring concrete, and comprises a steel shell and a core testing element in the steel shell, wherein the steel shell is magnetically sealed with the bottom of the steel plate; the core testing element comprises a hollow conduit, a sliding head, a pre-tightening spring and six arc-shaped steel belt strain gauges; the arc-shaped steel belt strain gauge comprises a pre-tightening arc-shaped steel belt and a resistance strain gauge attached to the pre-tightening arc-shaped steel belt, and six arc-shaped steel belt strain gauges are arranged in two groups along X, Y and Z directions, respectively, and are used for testing the slip amount along the X and Y directions and the peeling amount along the Z direction between the steel plate and the concrete. The application breaks through the defects of single testing direction and low testing dimension of the existing bond-slip testing, and significantly improves the feasibility of long-term monitoring of the interface damage of the composite structure.

The application discloses a kind of digital twin's fiber composite arch reinforced tunnel structure evaluation method, it is related to tunnel health monitoring technical field, establishes bonding slip model and total stress model, is combined with coupling temperature variation equation, coupling humidity variation equation, constructs damage rate model;Real-time data are collected, total stress is calculated after Gaussian process interpolation processing, calculate residual life and first assess whether to replace;When no replacement is needed in first assessment, future state is simulated using time series reasoning network and finite element method and life is assessed again to decide whether to replace lattice reinforced fiber composite arch, realize the dynamic evaluation and life prediction of lattice reinforced fiber composite arch reinforced tunnel structure, improve the evaluation accuracy and forwardness.

The application provides a joint bending stiffness calculation method, an electronic device and a storage medium. The method comprises the following steps: when a test beam is subjected to graded loading, the joint opening amount of the node area of the test beam and the actual strain of the anchorage reinforcement in the non-node area of the test beam under different load states are measured respectively; the structure parameters of the test beam are obtained, and the bond slip amount of the non-node area under different load states is calculated respectively according to the structure parameters and the actual strain; and the joint bending stiffness is calculated according to the bond slip amount and the joint opening amount. The application can improve the calculation accuracy of the joint bending stiffness of the anchorage joint.

The invention relates to the technical field of civil engineering materials, in particular to a fiber asphalt bond slip prediction method based on innovation-first fractional order accumulation, which comprises the following steps: firstly, selecting bond slip values obtained by performing monofilament drawing on basalt fibers in an asphalt matrix as a database, and constructing a non-negative original sequence as the input of a model; secondly, an innovation priority and fractional order accumulation operator is introduced when the model is constructed; then, a genetic algorithm is adopted to seek an optimal parameter in an innovation priority fractional order accumulation operator; and finally, applying the improved grey generalized Verhulst model to the bond slip curve prediction of the basalt fiber. According to the method, the interface performance evolution rule of the basalt fiber in the asphalt matrix can be well predicted, the influence of physical characteristics such as fiber modulus and surface morphology on interface stress transmission can be reflected, and a more reliable theoretical method is provided for predicting the interface performance of the fiber asphalt concrete.

The invention discloses a reinforcing steel bar and concrete interface displacement field testing method and device.The displacement field testing device is mainly composed of a top plate, a bottom plate, a balance plate, a lead screw assembly, a sleeve, an upper loading head, a lower loading head, a testing machine and a DIC testing device.According to the displacement field testing method, a shear test piece is fixed through the displacement field testing device; carrying out a shear experiment; collecting a speckle pattern of the interface through the DIC test device, and processing the speckle pattern to obtain a displacement field; the method comprises the following steps: firstly, dividing a single-side J-integral path in a displacement field, determining a change curve of single-side J-integral along with loading time through a J-integral calculation formula, finally, extracting axial strain of a stage line on the displacement field, and determining a bonding-slip curve by utilizing a relationship between interface shear stress and the axial strain. The method has the advantages of low experiment cost, high experiment success rate, simplicity and convenience in operation and the like.

The application discloses a built-in three-dimensional bond-slip testing device and a mounting testing method thereof, which is used for testing the bond-slip and vertical peeling at the interface of a steel plate-concrete composite structure, is mounted on the inner side of the steel plate before pouring the concrete, and comprises a steel shell and a core testing element located in the steel shell, wherein the steel shell is sealed with the bottom of the steel plate; the core testing element comprises a hollow conduit, a sliding head, a pre-tightening spring and six string strain gauges; two of the six string strain gauges are arranged along three directions of X, Y and Z respectively, and are used for testing the slip amount along the X and Y directions and the peeling amount along the Z direction between the steel plate and the concrete. The application is based on a novel internal structure, breaks through the defects of single testing direction and low dimension of the existing bond-slip testing, can realize the repetitive and intermittent non-continuous testing of the interface slip damage, and significantly improves the feasibility of long-term monitoring of the interface damage of the composite structure.

The present application relates to the field of building materials and structural engineering, and particularly relates to a method for analyzing the mechanical behavior of composite interface bonding. The method for analyzing the mechanical behavior of composite interface bonding comprises forming a composite interface; applying tensile load and alternating electric field in the axial and transverse directions of the modified carbon fiber respectively; establishing a three-linear bonding-slip constitutive model; measuring the phase angle of interface impedance in real time and calculating the interface damage index; correcting the three-linear bonding-slip constitutive model by using the damage index and analyzing the mechanical behavior of the composite interface bonding. The present application successfully deposits nano-SiO2 on the surface of carbon fiber, and also realizes the synchronous collection of interface slip, strain and impedance spectrum under multi-coupling stress, which facilitates the revelation of the synergistic mechanism of multi-field on interface damage.

The present application provides a kind of construction method of geopolymer coating bond-slip constitutive model, it is related to concrete bond-slip constitutive research technical field, the present application carries out center pull test to geopolymer coating steel reinforced concrete test piece, obtains loading end slip, free end slip and bond stress data;Calculate relative slip and average bond stress, analyze relative slip and average bond stress, obtain the relationship between relative slip length and average bond stress, the relationship between relative slip length and average bond stress is corrected by geopolymer influence coefficient;Bond stress data are analyzed, and the relationship between relative anchoring position and relative bond stress is obtained;According to the relationship between the corrected relative slip length and average bond stress, and the relationship between relative anchoring position and relative bond stress, the bond-slip constitutive relationship of geopolymer coating is constructed, and the bond-slip constitutive relationship of geopolymer coating is corrected based on complex network entropy flow logic.

The present invention discloses a method for calculating the bending bearing capacity of a prefabricated segmental beam bridge based on steel shear keys, and belongs to the technical field of prefabricated segmental beam bridges. Based on the concrete plasticity theory, the present invention constructs a theoretical force model of the plastic deformation of the prefabricated segmental beam bridge under bending, and establishes a calculation formula for the cracking bending moment of the three-section prefabricated segmental beam bridge, thereby improving the refinement and efficiency of the design; based on the fact that the bending bearing capacity at the joints of the segmental beams is mainly determined by the deformation of the compression zone of the concrete top plate and the ultimate stress of the steel strand, a calculation formula for the bending bearing capacity of the three-section prefabricated segmental beam bridge at the joints and non-joints is provided; taking into account the plastic deformation of the concrete and the bond-slip effect of the steel bars, the bending bearing capacity of the three-section prefabricated segmental beam bridge can be accurately calculated, and the safety and reliability of the calculation method are verified by comparison with the experimental values.

The invention relates to a method for calculating bonding slip of an embedded steel bar concrete member interface under the cyclic load effect, and belongs to the technical field of engineering structure reinforcement and transformation. The method sequentially comprises three parts of bonded stress analysis of embedded steel bars, calculation and correction of bond slip under the action of static load and calculation of bond slip under the action of cyclic load. According to the method, the influence of main factors such as the embedded steel bar diameter and the embedded steel bar anchoring depth of embedded steel bar bonding is considered, and the influence of key influence factors such as the embedded steel bar diameter and the embedded steel bar anchoring depth on the bonding force of the drawing bearing capacity of the embedded steel bar component is accurately described, so that a theoretical basis is provided for calculating the internal force and deformation of the embedded steel bar component; and the embedded steel bar reinforcement reconstruction engineering design is perfected.

The application provides a WGAN-based FRP sheet and concrete interface bonding slip model generation method, which can automatically, quickly and accurately obtain the bonding slip model and has a wide application prospect. After the automatic and rapid acquisition of the bonding slip model, the bonding performance between the FRP sheet and the concrete can be accurately reflected, and a safe and reliable reinforcement component design calculation method can be established. The WGAN is used to predict the strain, so that the training process can be simplified and the training can be stable. The WGAN can replace the traditional experimental analysis to quickly and accurately establish a bonding strength model. The LSTM is used as the generator of the WGAN model, so that the gradient disappearance and explosion problems of the RNN are solved, and the strain data related to time can be more accurately predicted. The CNN is used as the discriminator of the WGAN model, so that the quality and convergence speed of the generated samples are improved.

This invention belongs to the field of prefabricated bridges, specifically relating to a calculation method for the bond-slip relationship between energy-dissipating reinforcing bars and concrete in assembled bridge piers. The method includes the following steps: assembling the bridge pier; applying quasi-static loading to the assembled bridge pier; calculating the slip at the loading end of the energy-dissipating reinforcing bars; establishing an initial calculation model for the bond-slip relationship between the energy-dissipating reinforcing bars and concrete; calculating the average bond stress before and after yielding in the initial model based on measured and obtained data, thereby obtaining the final calculation models for the bond-slip relationship between the energy-dissipating reinforcing bars and concrete before and after yielding. This invention can be applied to measuring and calculating the bond-slip relationship between energy-dissipating reinforcing bars and concrete in different assembled bridge piers, and has engineering application value.

The invention discloses a calculation method of a bonding-sliding relation between a reinforcing steel bar and cracked concrete, which comprises the following steps: S1, pre-splitting a reinforced concrete drawing test piece through a universal testing machine to obtain pre-cracked reinforced concrete drawing test pieces with different crack parameters and reinforcing steel bar parameters; wherein the crack parameters comprise crack angles, and the steel bar parameters comprise steel bar diameters; s2, carrying out a pull-out test on the pre-cracked reinforced concrete pull-out test piece through a universal testing machine to obtain a bonding-sliding relation test curve of the reinforcing steel bar and the cracked concrete; s3, characteristic parameters are obtained according to the bond-slip relation test curve, the crack parameters and the steel bar parameters; and S4, according to the characteristic parameters, the bonding-sliding relation between the steel bars and the cracked concrete is constructed. The bond-slip curve of the reinforcing steel bar and the cracked concrete can be well predicted according to the bond-slip relation of the reinforcing steel bar and the cracked concrete, and a basis is provided for analyzing the bond property of the cracked concrete.

The utility model discloses a steel pipe and concrete interface bond-slip performance testing device, which solves the problem of lack of testing equipment for researching the bonding strength (single element) between a steel pipe and concrete. The testing device comprises a supporting frame, a supporting cylinder, a limiting ring and a concrete-filled steel tube test piece, the supporting cylinder is mechanically installed on the supporting frame and is in a suspended state, the concrete-filled steel tube test piece is located in the supporting cylinder, and the limiting ring is arranged between the supporting cylinder and the concrete-filled steel tube test piece. The at least two limiting rings are used for annularly restraining the upper end and the lower end of the concrete-filled steel tube test piece, and the pressure sensor is used for detecting the pressure stress in the concrete; the tensile stress strain gauge detects stress generated by expansion of the steel pipe. According to the utility model, the concrete filled steel tube sample inside is effectively placed, and a reasonable gap is kept between the sample and the supporting cylinder. Due to the existence of the gap, the sample has an external expansion space, so that experimental data are closer to reality.

The invention discloses a wind turbine foundation structure cracking research method based on global insertion of Cohesive units, and belongs to the technical field of wind turbine foundation cracking numerical simulation. Comprising the following steps: S1, constructing a fan foundation overall set model; s2, based on the fan basic overall set model, performing grid division through Hypermesh software, constructing a finite element grid model, and globally inserting a Cohesive unit through a code; s3, endowing the fan foundation overall set model with material attributes, and meanwhile, applying an interaction relationship between the concrete and the reinforcing steel bars by considering a bond-slip effect between the reinforcing steel bars and the concrete; s4, considering boundary conditions, loading the overall set model of the fan foundation, and performing finite element calculation on the model in which Cohesive is globally inserted to analyze cracks and mechanical behaviors of the cracks; while the precision of the model is maintained, the calculation cost can be remarkably reduced and the efficiency can be improved by optimizing the calculation process and reasonable grid division, so that the accurate capture of the structural crack behavior is ensured, and the possible high calculation requirement in the traditional method is avoided.

The application provides a mechanical property analysis method and system of CFRP grid reinforced concrete, parameters and loading schemes of a stress analysis model of a CFRP grid concrete beam are acquired, a linear softening model is used for a CFRP grid and a concrete interface bonding slip relationship; a known beam with the same height and bearing external bending moment is constructed; in a first stage with a crack bottom width less than a critical crack width, load, crack parameters and stress distribution characteristics in a crack expansion process are calculated according to geometric characteristics, concrete characteristics and CFRP characteristics of the known beam; in a second stage with the crack bottom width greater than or equal to the critical crack width, a force balance equation is described, a relationship between the crack bottom width and the compressive stress of the top of the section is defined, and the load, crack parameters and stress distribution characteristics in the crack expansion process are calculated. The application considers post-cracking tensile stress in the concrete, bonding slip behavior between the CFRP and the concrete, and the result is accurate.

The invention discloses a method for analyzing the bending performance of a steel-concrete sandwich panel based on strain monitoring, and relates to the technical field of structural performance evaluation, and the method comprises the following steps: S1, collecting cross section distributed strain data, and reconstructing a continuous strain field along the height direction of a cross section based on a spatial interpolation algorithm; based on the continuous strain field, dynamically tracking the position of a neutral shaft, and performing staged calculation to obtain a macroscopic bending moment-curvature relation and full-field deflection distribution; and S2, based on the continuous strain field, extracting strain data of paired sensors at the steel-concrete interface. According to the method for analyzing the bending performance of the steel-mixed-steel sandwich panel, the stress state of the cross section is finely described by reconstructing the continuous strain field, deviation caused by traditional discrete point monitoring and fixed assumption is overcome, and therefore the response process of the structure under the load effect is more truly reflected, and the bending performance of the steel-mixed-steel sandwich panel is improved. The dynamic quantitative evaluation of the steel and concrete bond slip behavior is realized.

This invention provides a method for reinforcing post-tensioned prestressed fiber-reinforced beams to control cracks in humid and hot environments. The specific steps are as follows: First, the area of ​​the bonded auxiliary fiber-reinforced reinforcement is obtained based on the lower limit of its reinforcement area. Second, a bond-slip model of the bonded auxiliary fiber-reinforced reinforcement and concrete is established under standard and humid and hot environments. The bond-slip constant and the amplification factor of the beam crack width under humid and hot environments are solved, and the height of the compression zone of the fiber-reinforced beam is obtained based on the amplification factor. Third, the area of ​​the i-th layer of unbonded prestressed fiber-reinforced reinforcement is obtained based on the minimum reinforcement area of ​​the i-th layer of unbonded prestressed fiber-reinforced reinforcement in the fiber-reinforced beam. Fourth, bonded auxiliary fiber-reinforced reinforcement and unbonded prestressed fiber-reinforced reinforcement are arranged, concrete is poured, and prestressing is applied to obtain the post-tensioned prestressed fiber-reinforced beam. This invention accurately and conveniently calculates the limit value of the reinforcement amount, avoiding repeated verification of the maximum crack width of the beam.

The invention discloses a method for evaluating a digital twin fiber composite arch reinforced tunnel structure, and relates to the technical field of tunnel health monitoring. A bond slip model and a total stress model are established, a coupling temperature change equation and a coupling humidity change equation are combined, and a damage rate model is constructed; collecting real-time data, calculating the total stress after Gaussian process interpolation processing, calculating the residual life, and primarily evaluating whether to replace or not; when replacement is not needed in primary evaluation, a future state is simulated by using a sequential reasoning network and a finite element method, and the service life is evaluated again to decide whether to replace the lattice reinforced fiber composite arch, so that dynamic evaluation and service life prediction of the lattice reinforced fiber composite arch reinforced tunnel structure are realized, and evaluation accuracy and perspectiveness are improved.