Door-shaped steel bar optimization method and system based on ballastless track interface damage analysis

Abstract

The invention provides a door-shaped steel bar optimization method and system based on ballastless track interface damage analysis, and relates to the field of track traffic, the method comprises the following steps: determining track interlayer bonding parameters of a ballastless track based on interface comprehensive mechanical property test data of a concrete material composite test piece of the ballastless track, and establishing a finite element model of the ballastless track; a service temperature field of the ballastless track is calculated, and equivalent simulation of shrinkage of the self-compacting concrete layer is completed; on the basis of the multiple structure optimization variables, multiple door-shaped steel bar optimization schemes are determined, and the track interface damage area and distribution of the ballastless track under the combined action of shrinkage of the self-compacting concrete layer and the temperature load are calculated by utilizing a finite element analysis method based on a finite element model of the ballastless track corresponding to the door-shaped steel bar optimization schemes; the method has the advantages that the early-stage interface damage risk is reduced, and the durability and reliability of the track structure are improved.

Description

Technical Field

[0001] The present invention relates to the field of rail transit, and particularly to a method and system for optimizing portal steel bars based on the analysis of interface damage of ballastless tracks. Background Art

[0002] A ballastless track is a railway track structure that does not use traditional ballast (stones). A ballastless track mainly consists of precast track slabs, a base slab, a self-compacting concrete filling layer, and portal steel bars in the middle. The rails are directly fixed to the subgrade or bridge through integral materials such as concrete and asphalt. Compared with traditional ballasted tracks, ballastless tracks have higher stability, durability, and maintenance efficiency, and are widely used in high-speed railways, urban rail transit, and other fields.

[0003] In actual operation, the problem of early interface damage of ballastless tracks has gradually emerged, mainly manifested as phenomena such as debonding and cracks between the track slab and the self-compacting concrete filling layer. These damages not only affect the smoothness and stability of the track, but may also lead to fatigue failure of the track structure, shorten its service life, and increase maintenance costs. Therefore, in-depth study of the causes of track interface debonding and the proposal of effective control measures have important practical significance for extending the service life of ballastless tracks and ensuring their operation safety. However, existing research mostly considers using methods such as implanting steel bars and interface adhesives to repair the already generated interface damage, without considering changing the distribution of some structures such as portal steel bars to inhibit the generation of damage.

[0004] Therefore, it is necessary to provide a method and system for optimizing portal steel bars based on the analysis of interface damage of ballastless tracks, which are used to reduce the risk of early interface damage and improve the durability and reliability of the track structure by optimizing the steel bar layout and parameters. Summary of the Invention

[0005] The present invention provides a method for optimizing portal steel bars based on the analysis of interface damage of ballastless tracks, including: determining the bonding parameters between track layers of ballastless tracks based on the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimens of ballastless tracks; establishing a finite element model of ballastless tracks based on the original design data of the portal steel bars of ballastless tracks and the bonding parameters between track layers; calculating the service temperature field of ballastless tracks and completing the equivalent simulation of the shrinkage of the self-compacting concrete layer; determining multiple optimization schemes for portal steel bars based on multiple structural optimization variables; for each optimization scheme of portal steel bars, generating a finite element model of the ballastless track corresponding to the optimization scheme of the portal steel bars based on the finite element model of the ballastless track, and calculating the damage area and distribution of the track interface of the ballastless track under the combined action of the shrinkage of the self-compacting concrete layer and temperature load by using the finite element analysis method based on the finite element model of the ballastless track corresponding to the optimization scheme of the portal steel bars; determining the optimal optimization scheme for portal steel bars based on the damage area and distribution of the track interface of the ballastless track corresponding to each optimization scheme of the portal steel bars.

[0006] Further, obtaining the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimens of ballastless tracks includes: performing a comprehensive mechanical property test on the interface of the concrete material composite specimens of ballastless tracks, wherein the comprehensive mechanical property test at least includes a splitting tensile test and a shear slip test; obtaining the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimens of ballastless tracks by combining the strain gauge test technology and the digital image correlation technology.

[0007] Further, determining the bonding parameters between track layers of ballastless tracks based on the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimens of ballastless tracks includes: analyzing the damage cracking behavior of the concrete material composite specimens of ballastless tracks during the comprehensive mechanical property test based on the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimens of ballastless tracks, and determining the bonding parameters between track layers of ballastless tracks.

[0008] Further, establishing a finite element model of ballastless tracks based on the original design data of the portal steel bars of ballastless tracks and the bonding parameters between track layers includes: establishing models corresponding to multiple components of ballastless tracks based on the original design data of the portal steel bars of ballastless tracks and assigning material properties, wherein the multiple components at least include portal steel bars and track structure reinforcement; establishing a cohesive force model based on the bonding parameters between track layers of ballastless tracks, and simulating the bonding relationship between the track slab and the self-compacting concrete layer of ballastless tracks through the cohesive force model; establishing a finite element model of ballastless tracks based on the models corresponding to multiple components of ballastless tracks and the bonding relationship between the track slab and the self-compacting concrete layer.

[0009] Furthermore, calculate the service temperature field of the ballastless track, including: establishing the heat conduction differential equation of the ballastless track based on the material properties, service environment, meteorological factors, and three heat transfer modes of solar radiation, convective heat transfer, and radiative heat transfer of the ballastless track; using the integral transform method to solve the heat conduction differential equation of the ballastless track and determining the analytical expressions of the temperature fields of each layer structure of the ballastless track.

[0010] Furthermore, complete the equivalent simulation of the shrinkage of the self-compacting concrete layer, including: determining the equivalent maximum temperature drop; based on the equivalent maximum temperature drop, the service temperature field of the ballastless track, and the finite element model of the ballastless track, completing the equivalent simulation of the shrinkage of the self-compacting concrete layer.

[0011] Furthermore, use the finite element analysis method to calculate the damage area and distribution of the track interface of the ballastless track under the combined action of the shrinkage of the self-compacting concrete layer and temperature load based on the finite element model of the ballastless track corresponding to the optimized portal reinforcement scheme, including: determining the target working condition; applying the temperature load and shrinkage effect based on the target working condition; based on the finite element model of the ballastless track corresponding to the optimized portal reinforcement scheme, calculating the damage area and distribution of the track interface of the ballastless track under the combined action of the shrinkage of the self-compacting concrete layer and temperature load.

[0012] Furthermore, determine multiple optimized portal reinforcement schemes based on multiple structural optimization variables, including: taking the distribution position of the portal reinforcement, the spacing between adjacent portal reinforcements, and the transverse span of the portal reinforcement as variables to determine multiple optimized portal reinforcement schemes.

[0013] Furthermore, determine the optimal portal reinforcement scheme based on the damage area and distribution of the track interface of the ballastless track corresponding to each optimized portal reinforcement scheme, including: taking the distribution position of the portal reinforcement as a variable to determine multiple first optimized portal reinforcement schemes; based on the damage area and distribution of the track interface of the ballastless track corresponding to each first optimized portal reinforcement scheme, determining the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure; according to the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure, taking the spacing between adjacent portal reinforcements as a variable to determine multiple second optimized portal reinforcement schemes; based on the damage area and distribution of the track interface of the ballastless track corresponding to each second optimized portal reinforcement scheme, determining the optimal spacing between adjacent portal reinforcements; according to the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure and the optimal spacing between adjacent portal reinforcements, taking the transverse span of the portal reinforcement as a variable to determine multiple third optimized portal reinforcement schemes; based on the damage area and distribution of the track interface of the ballastless track corresponding to each third optimized portal reinforcement scheme, determining the optimal transverse span of the portal reinforcement; based on the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure, the optimal spacing between adjacent portal reinforcements, and the optimal transverse span of the portal reinforcement, determining the optimal portal reinforcement scheme.

[0014] The present invention provides a portal steel bar optimization system based on the analysis of the interface damage of ballastless tracks, which applies the above-mentioned portal steel bar optimization method based on the analysis of the interface damage of ballastless tracks, including: a parameter determination module, which is used to determine the interlayer bonding parameters of the ballastless track based on the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimen of the ballastless track; a model establishment module, which is used to establish a finite element model of the ballastless track based on the original design data of the portal steel bar of the ballastless track and the interlayer bonding parameters; a shrinkage simulation module, which is used to calculate the service temperature field of the ballastless track and complete the equivalent simulation of the concrete shrinkage; a scheme determination module, which is used to determine multiple portal steel bar optimization schemes based on multiple structural optimization variables; a scheme analysis module, which is used for each portal steel bar optimization scheme, based on the finite element model of the ballastless track, to generate a finite element model of the ballastless track corresponding to the portal steel bar optimization scheme, and use the finite element analysis method to calculate the damage area and distribution of the track interface of the ballastless track under the combined action of concrete shrinkage and temperature load based on the finite element model of the ballastless track corresponding to the portal steel bar optimization scheme; a scheme screening module, which is used to determine the optimal portal steel bar optimization scheme based on the damage area and distribution of the track interface of the ballastless track corresponding to each portal steel bar optimization scheme.

[0015] Compared with the prior art, the portal steel bar optimization method and system based on the analysis of the interface damage of ballastless tracks provided by the present invention have at least the following beneficial effects: 1. By determining the interlayer bonding parameters of the track based on the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimen and establishing a finite element model accordingly, the actual bonding state between the track layers can be simulated more accurately. This helps to optimize the design of the portal steel bars, make the bonding between the track layers closer, reduce the occurrence of diseases such as interlayer separation and track warping, and thus improve the overall stability and durability of the track structure. By determining multiple portal steel bar optimization schemes based on multiple structural optimization variables and using the finite element analysis method to calculate the damage area and distribution of the track interface under different schemes, the optimal scheme can be selected. This optimized design can make the portal steel bars better adapt to the stress characteristics of the ballastless track, improve the bearing capacity and crack resistance of the steel bars, and effectively control the generation and development of cracks in the track structure.

[0016] 2. By calculating the service temperature field of the ballastless track and completing the equivalent simulation of the shrinkage of the self-compacting concrete layer, the temperature changes and concrete shrinkage and other influencing factors faced by the ballastless track during actual operation can be reflected more realistically. Based on this, finite element analysis can make the calculation results closer to the actual situation and improve the accuracy and reliability of the track structure design. By using the finite element analysis method to calculate the damage area and distribution of the track interface of the ballastless track under the combined action of the shrinkage of the self-compacting concrete layer and temperature load for different portal steel bar optimization schemes, the damage situation of the track interface can be comprehensively and intuitively understood, providing a scientific basis for selecting the optimal scheme.

[0017] 3. The optimized portal reinforcement design can improve the overall performance of the track structure, reduce the occurrence of diseases such as track interface damage and cracks. This will reduce the maintenance frequency and difficulty during the operation of the track structure, and reduce the outage time and economic losses caused by disease maintenance. By optimizing the portal reinforcement design and improving the durability of the track structure, the service life of the ballastless track can be extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] This specification will be further described by way of exemplary embodiments, which will be described in detail through the drawings. These embodiments are not restrictive. In these embodiments, the same numbers represent the same structures, where: Figure 1 is a schematic flow chart of a method for optimizing portal reinforcement based on the analysis of ballastless track interface damage shown in some embodiments of this specification; Figure 2 is a schematic diagram of the verification results of the normal parameters shown in some embodiments of this specification; Figure 3 is a schematic diagram of the verification results of the tangential parameters shown in some embodiments of this specification; Figure 4 is a schematic diagram of the finite element model of the ballastless track shown in some embodiments of this specification; Figure 5 is a schematic diagram of the original layout plan of the portal reinforcement of the ballastless track shown in some embodiments of this specification; Figure 6 is a schematic diagram of the damage and failure area of different first portal reinforcement optimization schemes shown in some embodiments of this specification; Figure 7 is a schematic diagram of the damage distribution of different first portal reinforcement optimization schemes shown in some embodiments of this specification; Figure 8 is a schematic diagram of the damage and failure area of different second portal reinforcement optimization schemes shown in some embodiments of this specification; Figure 9 is a schematic diagram of the damage distribution of different second portal reinforcement optimization schemes shown in some embodiments of this specification; Figure 10 is a schematic diagram of the damage and failure area of different third portal reinforcement optimization schemes shown in some embodiments of this specification; Figure 11 is a schematic diagram of the damage distribution of different third portal reinforcement optimization schemes shown in some embodiments of this specification; Figure 12 is a schematic diagram of the optimal portal reinforcement optimization scheme shown in some embodiments of this specification; Figure 13 It is a schematic diagram of the damage and failure area of the optimal portal steel bar optimization scheme shown in some embodiments of this specification; Figure 14 It is a schematic diagram of the damage distribution of the optimal portal steel bar optimization scheme shown in some embodiments of this specification; Figure 15 It is a schematic diagram of the modules of the portal steel bar optimization system based on the analysis of the ballastless track interface damage shown in some embodiments of this specification. Detailed implementation manners

[0019] To more clearly illustrate the technical solutions of the embodiments of this specification, the accompanying drawings required for the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some examples or embodiments of this specification. For those of ordinary skill in the art, without creative efforts, this specification can also be applied to other similar scenarios based on these drawings. Unless obvious from the language context or otherwise stated, the same reference numerals in the figures represent the same structure or operation.

[0020] Figure 1 It is a schematic flow diagram of the portal steel bar optimization method based on the analysis of the ballastless track interface damage shown in some embodiments of this specification. As Figure 1 shown, the portal steel bar optimization method based on the analysis of the ballastless track interface damage may include the following steps.

[0021] Step 110, determine the interlayer bonding parameters of the ballastless track based on the interface comprehensive mechanical property test data of the concrete material composite specimen of the ballastless track.

[0022] Preferably, obtaining the interface comprehensive mechanical property test data of the concrete material composite specimen of the ballastless track includes: Conduct an interface comprehensive mechanical property test on the concrete material composite specimen of the ballastless track, where the interface comprehensive mechanical property test includes at least a splitting tensile test and a shear slip test; Obtain the interface comprehensive mechanical property test data of the concrete material composite specimen of the ballastless track by combining the strain gauge test technology and the digital image correlation technology.

[0023] Specifically, the fabrication and molding of the concrete material composite specimen of the ballastless track mainly include several processes such as mixing, vibrating, demolding, and curing. First, select a lightweight and easy-to-demold cubic plastic integral test mold, and refer to standards such as "Standard for Test Methods of Physical and Mechanical Properties of Concrete GB / T 50081-2019". The specimen is selected as a standard-size cubic test block with dimensions of 150×150×150mm 3, self-compacting concrete and track slab concrete each account for half, that is, their sizes are both 150×150×75mm 3 , apply an appropriate amount of release agent (gasoline engine oil) evenly on its inner wall before pouring to facilitate demoulding. Use a self-falling mixer to mix the concrete to ensure the uniformity and fluidity of the concrete. Subsequently, complete the vibration work of the concrete through a plate vibrator to ensure its density. After the concrete is poured, the demoulding time is 24 - 48 hours after the initial setting, and high-pressure air is used to "blow" the specimen out of the mold. To ensure the good quality of the specimen, the specimen needs to be kept moist during the curing process, and film covering and sprinkler curing are carried out at different stages to ensure that the concrete meets the specified strength and performance requirements. Through batch production with molds, ensure that the size of each specimen is consistent and meets the test standards.

[0024] Refer to relevant specifications such as "Standard Test Method for Mechanical Properties of Ordinary Concrete" (GB / T 50081 - 2002) and "Test Code for Hydraulic Concrete" (DL / T 5150 - 2017) to conduct comprehensive interface mechanical property tests, including splitting tensile test and shear slip test (specimen installation and fixation, interface bonding strength test); Splitting tensile test: Use a steel arc-shaped pad with a radius of 75mm to load the specimen, and place a plywood spacer between the pad and the specimen. The lower steel pad is fixed to the base of the testing machine, and the upper steel pad is connected to the upper movable loading platform of the testing machine through a hinge to ensure uniform stress on the upper and lower surfaces of the specimen. After the specimen is placed, apply a pre-pressure of 1kN to make the steel pad and the specimen in close contact, and paste strain gauges near the interface to measure the normal strength. When the strain value changes suddenly, judge that the interface cracks, record the load value at this time, and calculate the interface normal strength. Shear slip test refers to "Code for Rock Tests in Railway Engineering" (TB 10115 - 2014), and use an angle die shearing device with a variable angle range of 30° - 70° to load the specimen. Place a steel backing plate between the shearing device and the specimen to increase the load-bearing area. Fix the variable angle plate and the shear fixture, adjust the fixture angle to the required value, and then install the specimen in the variable angle plate. Select an automatic temperature-compensated strain gauge, and paste the strain gauge across the interface and fix the copper wire with insulating putty. Apply a vertical load through a press to cause the specimen to shear failure along the bonding interface, and use the static equilibrium condition to analyze the normal compressive stress and shear stress on the shear plane, so as to calculate the interface tangential strength.

[0025] By combining the strain gauge test technology with the Digital Image Correlation (DIC) technology, the damage and cracking behavior of the bonding interface of concrete specimens during normal splitting tension and tangential slip processes is analyzed. The test system consists of two high-definition cameras and a 200W stroboscopic-free cold white LED lighting. The VIC-2D photogrammetry system is used to capture two-dimensional deformation information. Before the test, a matte paint is sprayed on the surface of the specimen and marked with black speckles. After the test, the DIC post-processing software is used to analyze the dynamic evolution process of the interface. Combining data such as the strain field and stress-strain curve to obtain the interlayer bonding parameters of the track.

[0026] When observing the damage and cracking behavior of the bonding interface of concrete specimens during normal splitting tension and tangential slip, the Digital Image Correlation (DIC) technology is adopted to capture the entire process of interface cracking. The digital correlation technology test system consists of two high-definition cameras with a resolution of 1250×800 pixels. In addition to the cameras, it also includes an illumination system, which consists of two 200W stroboscopic-free cold white light source LEDs. Considering that the interface damage evolution process on the surface of the measured concrete specimen is two-dimensional deformation, the VIC-2D photogrammetry system is used to measure the shape, movement, and deformation of the specimen under quasi-static load. The digital image correlation technology uses the dense random speckles on the surface of the specimen to obtain the deformation information of the bonding interface. Before the test, a matte paint is sprayed on the surface of the specimen to form a very thin white paint surface, and a large number of dense random black speckles are marked on the sprayed matte paint surface using the speckle making tool in the DIC equipment. After the test is completed, the DIC post-processing related software is used to process and analyze the dynamic evolution process of the concrete bonding interface. The interlayer strain information is extracted from the image data collected by DIC, and the variation law of the strain field during the loading process is analyzed. Combining the obtained experimental results such as the strain field and stress-strain curve, the damage evolution process of the bonding interface of the concrete composite specimen can be analyzed. Among them, the stress-strain curve reflects the mechanical behavior of the interlayer bonding interface at different loading stages, including the elastic stage, yield stage, and failure stage.

[0027] Preferably, step 110 specifically includes: Based on the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimen of the ballastless track, analyze the damage and cracking behavior of the concrete material composite specimen of the ballastless track during the test of the comprehensive mechanical properties of the interface, and determine the interlayer bonding parameters of the ballastless track.

[0028] Specifically, based on the strain rosette attached to one side of the track slab concrete during the test, according to Hooke's law of elasticity, the horizontal stress at the measuring point, that is, the track concrete, can be obtained as: , In the formula: is the horizontal stress of the concrete at the measurement point, that is, the stress perpendicular to the interface direction. E is the elastic modulus of the concrete corresponding to the strain gauge pasting position, and ν is the Poisson's ratio. and are the lateral and vertical strains of the concrete at the measurement point, respectively. The normal stress at the measurement point is approximately equal to the normal tension of the interface: , Substituting the measured lateral strain , vertical strain data, the normal tension of the interface can be obtained. Thus, the relationship between the normal stress and the opening displacement of the interface, that is, the interface stress-strain relationship, can be obtained. Furthermore, the normal cohesive force parameters required in the ABAQUS software can be obtained, including the normal stiffness (the ratio of the ordinate to the abscissa of the curve vertex), the normal strength (the ordinate of the curve vertex), and the normal fracture energy (the area of the curve).

[0029] By analyzing the two observation points at both ends of the interface during the slip failure process of the interface, it is necessary to ensure that the two points are symmetric about the interface. The tangential displacements and of points a and b along the interface obtained by testing and the evolution process over time, and the shear strain of point a are obtained. Then the tangential displacement of the interface can be expressed as the tangential displacement between a and b: , According to the generalized Hooke's law, the shear stress value of point a is: , where G is the shear modulus, and G = 0.4E.

[0030] At points a and b near the interface crack, the tangential cohesive stress can be expressed as: .

[0031] Subsequently, eliminating the time variable t from the obtained tangential cohesive force and tangential displacement curve, the relationship between the tangential stress and the slip displacement of the interface can be obtained. Furthermore, the tangential stress-strain constitutive relationship curves of the tangential cohesive force and the slip displacement of the interface of the ballastless track concrete composite specimen in the shear test are obtained by sorting. Furthermore, the tangential cohesive force parameters required in the ABAQUS software can be obtained, including the tangential stiffness (the ratio of the ordinate to the abscissa of the curve vertex), the tangential strength (the ordinate of the curve vertex), and the tangential fracture energy (the area of the curve).

[0032] Figure 2 is a schematic diagram of the verification results of the normal parameters shown in some embodiments of this specification. Figure 3It is a schematic diagram of the verification result of the tangential parameter shown in some embodiments of this specification. As Figure 2 and Figure 3 shown, after obtaining the bonding parameters between the track layers, a finite element model of the concrete material composite specimen is established. Through finite element analysis based on the finite element model of the concrete material composite specimen, the stress-displacement curve of the bonding interface of the track structure is calculated. The stress-displacement curve of the bonding interface of the track structure calculated based on the established finite element model of the concrete material composite specimen fits well with the test results, verifying the accuracy of the cohesive force model in characterizing the bonding relationship between the track layers.

[0033] Step 120: Based on the original design data of the portal steel bars of the ballastless track and the bonding parameters between the track layers, establish a finite element model of the ballastless track.

[0034] Preferably, step 120 specifically includes: Based on the original design data of the portal steel bars of the ballastless track, establish models corresponding to multiple components of the ballastless track and assign material properties. Among them, the multiple components at least include portal steel bars and track structure reinforcement bars. Specifically, taking the CRTS III type ballastless track as an example, Figure 4 It is a schematic diagram of the finite element model of the ballastless track shown in some embodiments of this specification. As Figure 4 shown, relevant data can be sorted out according to the ballastless track design drawings, and finite element models of the rail, track slab, self-compacting concrete layer, base slab, subgrade, and steel bars are established respectively and their material properties are assigned. Compared with the previously established finite element models, the finite element model established by this method finely considers the portal steel bars and track structure reinforcement bars, can better simulate the structural stress and state of the ballastless track, and the calculation results are more accurate; Based on the bonding parameters between the track layers of the ballastless track, establish a cohesive force model, and simulate the bonding relationship between the track slab and the self-compacting concrete layer of the ballastless track through the cohesive force model. Specifically, a bilinear cohesive force model is established based on the finite element software ABAQUS using the quadratic stress criterion and energy criterion. Cut a 1 mm thickness on the upper surface of the self-compacting concrete and assign cohesive force materials and element properties to simulate the bonding relationship between the self-compacting concrete layer and the track slab; Based on the models corresponding to multiple components of the ballastless track and the bonding relationship between the track slab and the self-compacting concrete layer, establish a finite element model of the ballastless track. Specifically, divide the grid and assemble the components of the ballastless track, finely consider and give the interaction relationship between the components. For example, in past studies, the track slab and the self-compacting concrete were regarded as a composite slab, while this method adds a cohesive force model established based on the bonding parameters between the track layers of the ballastless track and considers the embedding of the portal steel bars, making the established finite element model of the ballastless track more in line with the actual situation and improving the calculation accuracy.

[0035] Specifically, after obtaining the interfacial bonding parameters between the tracks, a finite element model of the concrete composite specimen is established. Based on the finite element model of the concrete composite specimen through finite element analysis, the stress-displacement curve of the bonding interface of the track structure is calculated. The stress-displacement curve of the bonding interface of the track structure calculated based on the established finite element model of the concrete composite specimen fits well with the test results, verifying the accuracy of the cohesive force model in characterizing the interfacial bonding relationship between the tracks.

[0036] Only as an example, considering the influence of boundary effects, the length of the finite element model established using ABAQUS software is 16.94 m, which is the length of three track slabs. The middle track slab and the self-compacting concrete layer structure are taken as the research objects. According to Figure 5 The portal reinforcement is established according to the original layout scheme of the portal reinforcement shown. The beam element is used to simulate the reinforcement of the track structure and the portal reinforcement, and it is embedded in the track slab and the self-compacting concrete layer structure.

[0037] Step 130, calculate the service temperature field of the ballastless track and complete the equivalent simulation of the shrinkage of the self-compacting concrete layer.

[0038] Preferably, calculating the service temperature field of the ballastless track includes: Based on the material properties of the ballastless track, the service environment (e.g., geographical location), meteorological factors (such as temperature, humidity, wind speed, etc.), and three heat transfer modes of solar radiation, convective heat transfer, and radiative heat transfer, establish the heat conduction differential equation of the ballastless track; Use the integral transform method to solve the heat conduction differential equation of the ballastless track and determine the analytical expression of the temperature field of each layer structure of the ballastless track.

[0039] Specifically, select an appropriate integral transform (such as Laplace transform, Fourier transform, etc.) to transform the heat conduction differential equation into an ordinary differential equation or an algebraic equation, thereby simplifying the solution process. Use mathematical methods (such as the method of separating variables, eigenvalue method, etc.) to solve the transformed equation to obtain the analytical expression of the temperature field. According to the obtained analytical expression, combined with the geometric dimensions and material distribution of the ballastless track, determine the temperature field distribution of each layer structure (such as track slab, self-compacting concrete layer, base slab, etc.).

[0040] Preferably, completing the equivalent simulation of the shrinkage of the self-compacting concrete layer includes: Determine the equivalent maximum temperature drop. For example, referring to the "Code for Design of High-Speed Railways", the early shrinkage of the self-compacting concrete is considered and simulated according to the equivalent maximum temperature drop of -10 °C. Based on the equivalent maximum temperature drop, the service temperature field of the ballastless track, and the finite element model of the ballastless track, complete the equivalent simulation of the shrinkage of the self-compacting concrete layer.

[0041] For example, based on the ABAQUS software, taking the temperature change of the self-compacting concrete layer as the boundary condition, referring to the "Code for Design of High-Speed Railways", the early shrinkage of the self-compacting concrete is simulated according to the equivalent maximum temperature drop of -10°C. Therefore, in the ABAQUS software, the temperature of the self-compacting concrete layer is reduced by -10°C based on the pouring temperature to simulate the shrinkage of the self-compacting concrete layer. When the self-compacting concrete hardens in the early stage, the internal cement hydration reaction will generate heat, and at the same time, the evaporation of water will cause volume shrinkage. If this shrinkage is restricted, tensile stress will be generated inside the concrete. When the tensile stress exceeds the tensile strength of the concrete, cracks may be induced. The simulation method of the equivalent maximum temperature drop of -10°C is to equivalent the early shrinkage deformation of the concrete to the thermal shrinkage deformation caused by the temperature drop. Because the temperature drop will cause the concrete to shrink, by setting an equivalent temperature drop of -10°C, the influence degree of the early shrinkage of the self-compacting concrete on the ballastless track structure can be simulated. When simulating the shrinkage of the self-compacting concrete layer, taking the finite element model of the ballastless track as the basis, and inputting the equivalent maximum temperature drop and the service temperature field into the model as boundary conditions or initial conditions. The finite element model can calculate the mechanical parameters such as the displacement and stress of each node in the ballastless track structure according to the input conditions, so as to simulate the influence of the shrinkage of the self-compacting concrete layer on the ballastless track structure. In the ABAQUS software, the temperature change of the self-compacting concrete layer is input into the model as the boundary condition. Specifically, based on the pouring temperature of the self-compacting concrete layer, it is reduced by -10°C to simulate its shrinkage. The pouring temperature refers to the initial temperature of the self-compacting concrete during pouring. Since the equivalent maximum temperature drop is -10°C, the temperature of the self-compacting concrete layer is set in the software to be the pouring temperature minus 10°C. After simulation by the ABAQUS software, the deformation and stress distribution of the ballastless track structure under the action of the shrinkage of the self-compacting concrete layer can be obtained.

[0042] Step 140: Determine multiple optimized gantry reinforcement schemes based on multiple structural optimization variables.

[0043] Preferably, step 140 specifically includes: Taking the distribution position of the gantry reinforcement, the spacing between adjacent gantry reinforcements, and the transverse span of the gantry reinforcement as variables, determine multiple optimized gantry reinforcement schemes.

[0044] Specifically, in order to ensure sufficient bond strength between the gantry reinforcement and the surrounding concrete, and at the same time avoid too dense reinforcement arrangement, the spacing between the gantry reinforcement and the adjacent longitudinal and transverse reinforcements needs to be reasonably set. According to relevant specifications, the minimum clear spacing of the reinforcement should not be less than 25 mm or 1.5 times the reinforcement diameter. Considering the economy of the structural reinforcement and the filling effect of the self-compacting concrete comprehensively, the minimum distance between the longitudinal and transverse directions of the gantry reinforcement from the free edge of the track structure is finally determined to be 120 mm.

[0045] Step 150: For each optimized portal steel bar scheme, based on the finite element model of the ballastless track, generate the finite element model of the ballastless track corresponding to the optimized portal steel bar scheme. Using the finite element analysis method, based on the finite element model of the ballastless track corresponding to the optimized portal steel bar scheme, calculate the damage area and distribution of the track interface of the ballastless track under the combined action of the shrinkage of the self-compacting concrete layer and the temperature load.

[0046] Preferably, using the finite element analysis method, based on the finite element model of the ballastless track corresponding to the optimized portal steel bar scheme, calculating the damage area and distribution of the track interface of the ballastless track under the combined action of the shrinkage of the self-compacting concrete layer and the temperature load includes: Determine the target working condition; Apply the temperature load and shrinkage effect based on the target working condition; Based on the finite element model of the ballastless track corresponding to the optimized portal steel bar scheme, calculate the damage area and distribution of the track interface of the ballastless track under the combined action of the shrinkage of the self-compacting concrete layer and the temperature load.

[0047] Specifically, when the track structure is in service, it bears the combined action of various loads, among which the concrete shrinkage and temperature load are key factors. Considering the actual engineering situation, the influence of extreme high temperature and harsh working conditions in summer on the track structure is more significant. At the same time, to compare the influence under different temperature conditions, the extreme low temperature working condition is also considered. Through the comparison of previous research, it is found that the damage to the track interface is more serious under the combined action of concrete shrinkage and extreme high temperature load. Therefore, in the subsequent optimization analysis of the portal steel bar on the track interface damage, select the extreme high temperature weather (for example, the temperature exceeds 40 degrees Celsius) as the target working condition because it represents the most severe working condition, and studying the damage situation under this working condition is of great significance for the optimized design.

[0048] Based on the solution results of the nonlinear distribution of the temperature field of the ballastless track with depth completed previously, use the change of the temperature field with the depth of the track structure as the boundary condition to simulate the temperature change after the ballastless track is poured. Select the extreme high temperature weather and extreme low temperature weather in Shenyang, and calculate the temperature distribution changes of the track structure on these two days respectively. The calculation results of the temperature field provide accurate data support for the subsequent application of the temperature load. In the finite element model, apply the calculated temperature field as the boundary condition to the ballastless track structure. The temperature values at different depth positions correspond to the node temperatures, and in this way, the influence of the actual temperature on the track structure is simulated.

[0049] According to the simulation results of the equivalent simulation of the shrinkage of the self-compacting concrete layer, determine the shrinkage amount of the self-compacting concrete under the target working conditions. In the finite element model, the shrinkage of the self-compacting concrete is equivalent to the shrinkage deformation caused by the temperature drop (such as the equivalent maximum temperature drop of -10°C), and the corresponding temperature is reduced on the basis of the pouring temperature of the self-compacting concrete layer to simulate its shrinkage. The shrinkage effect is applied to the self-compacting concrete layer in the form of displacement boundary conditions or initial strains to simulate the influence of its shrinkage deformation during the hardening process on the track structure.

[0050] After applying the temperature load and shrinkage effect in the finite element model, perform finite element analysis and calculation. According to the selected damage criterion, calculate the damage values of each node at the track interface. By analyzing the distribution of the damage values, determine the damage area and distribution at the track interface. For example, set a damage threshold. When the damage value of a node exceeds this threshold, it is considered that the node is damaged, and count the number and distribution area of the damaged nodes, so as to obtain the damage area and distribution at the track interface.

[0051] Step 160, based on the damage area and distribution at the track interface of the ballastless track corresponding to each optimized portal reinforcement scheme, determine the optimal portal reinforcement optimization scheme.

[0052] Specifically, the basic principles followed by the optimized layout scheme of the portal reinforcement are as follows: 1. Considering that the initial portal reinforcement layout scheme already has a certain degree of rationality, no subversive adjustment is made to it; 2. During the early service process of the track structure, it is relatively acceptable that interlayer damage appears at the free edge of the track. As long as the rapid expansion of the damage to the area under the rail can be effectively prevented, time can be gained for the maintenance of the track structure; 3. When optimizing the layout of the portal reinforcement, it is also necessary to consider the coordination of its position with the longitudinal and transverse reinforcement in the slab, and at the same time comprehensively consider the economy of the structural reinforcement and the filling effect of the self-compacting concrete, and avoid the portal reinforcement being arranged too densely.

[0053] Preferably, step 160 specifically includes: Taking the distribution position of the portal reinforcement as a variable, determine a variety of first portal reinforcement optimization schemes; Based on the damage area and distribution at the track interface of the ballastless track corresponding to each first portal reinforcement optimization scheme, determine the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure; According to the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure, taking the spacing between adjacent portal reinforcements as a variable, determine a variety of second portal reinforcement optimization schemes; Based on the damage area and distribution at the track interface of the ballastless track corresponding to each second portal reinforcement optimization scheme, determine the optimal spacing between adjacent portal reinforcements; Determine multiple optimized third portal steel bar schemes with the transverse span of the portal steel bar as a variable according to the optimal distances of the longitudinal and transverse directions of the portal steel bar from the free edge of the track structure and the optimal spacing between adjacent portal steel bars; Determine the optimal transverse span of the portal steel bar based on the damage area and distribution of the track interface of the ballastless track corresponding to each optimized third portal steel bar scheme; Determine the optimal portal steel bar optimization scheme based on the optimal distances of the longitudinal and transverse directions of the portal steel bar from the free edge of the track structure, the optimal spacing between adjacent portal steel bars, and the optimal transverse span of the portal steel bar.

[0054] As an example, as Figure 6 、 7 shown, study the influence of the distribution position of the portal steel bar on the damage of the track structure interface, and then select the minimum distances of 200 mm, 150 mm, and 120 mm respectively for comparative analysis to select the distribution position of the portal steel bar. Comparative analysis shows that setting the minimum distance of the portal steel bar in the longitudinal and transverse directions from the free edge of the track structure to 120 mm has the best effect. Compared with the original scheme, the damage area and failure area are reduced by 29.9% and 33.3% respectively. Among them, Figure 7 in, (a) corresponds to the original scheme, (b) corresponds to the scheme with l = 200 mm, (c) corresponds to the scheme with l = 150 mm, and (d) corresponds to the scheme with l = 120 mm.

[0055] It can be found through Figure 7 that when the spacing between adjacent portal steel bars is large, the interface damage will extend horizontally between adjacent portal steel bars. When the spacing between adjacent portal steel bars is 200 mm, the horizontal expansion of the interface damage can be effectively inhibited. Therefore, consider encrypting the portal steel bars at the wide-spacing locations to inhibit the expansion of the track interface damage. To avoid the too-dense arrangement of steel bars affecting the filling effect of self-compacting concrete and increasing the steel bar cost, the spacing encryption scheme is selected to encrypt a group at the voids with a spacing greater than 300 mm. According to Figure 8 and Figure 9 it can be seen that the adopted spacing encryption scheme has a significant effect. Compared with the original scheme, the damage and failure areas are reduced by 57.9% and 61.8% respectively. However, the amount of portal steel bars in the original design scheme is 33.9 kg, while the amount in the encrypted design scheme is 54.24 kg, which is 60% more than the original scheme. Among them, Figure 9 in, (a) corresponds to the original scheme, (b) corresponds to the encryption of the original scheme, (c) corresponds to the scheme with l = 200 mm, and (d) corresponds to the encryption of the scheme with l = 120 mm.

[0056] Figure 8 and Figure 9 it can be seen that encrypting the portal steel bars significantly inhibits the track interface damage but also significantly increases the amount of portal steel bars. In addition, from Figure 7It can be seen that when the horizontal span of the portal-shaped steel bars is 240 mm, the damage to the track interface longitudinally expands in the middle of a single portal-shaped steel bar. Therefore, it is considered to reduce the horizontal span of the portal-shaped steel bars to inhibit the expansion of the track interface damage, reduce the amount of portal-shaped steel bars used, and improve the economy of the scheme. The expansion of the track interface damage can be inhibited by reducing the horizontal span of the portal-shaped steel bars, the amount of portal-shaped steel bars used can be reduced, and the economy of the scheme can be improved, as Figure 10 and 11 shown. Compared with the original scheme, the damaged and failed areas are reduced by 59.4% and 65.0% respectively. Therefore, the span of the portal-shaped steel bars is selected to be 120 mm. Among them, Figure 11 in, (a) corresponds to the original scheme with encryption, (b) corresponds to the original scheme with the encryption size halved, (c) corresponds to the scheme with l = 120 mm with encryption, and (d) corresponds to the scheme with l = 120 mm with the encryption size halved.

[0057] From Figure 11 it can be seen that when only 5 groups of portal-shaped steel bars with a horizontal span of 120 mm are set at the plate end, the damage to the track interface will still longitudinally expand from the middle of two adjacent portal-shaped steel bars at the plate end. Therefore, as Figure 12 shown, the final optimal optimization scheme for portal-shaped steel bars is as follows: shorten the horizontal span of the portal-shaped steel bars from 240 mm to 120 mm, and move the longitudinally and horizontally arranged portal-shaped steel bars as a whole to a position 120 mm away from the edge of the track slab. At the same time, add a group of portal-shaped steel bars in the gap with a spacing greater than 300 mm, and set 7 groups of portal-shaped steel bars at the plate end. Through the above optimization, the total amount of steel bars used is 43.22 kg.

[0058] As Figure 13 and 14 shown, by comparison, the optimal optimization scheme for portal-shaped steel bars reduces the interface damage and failure areas by 64.9% and 70.8% respectively, only on the premise of increasing the total amount of steel bars used by 27.4% compared with the original scheme. Among them, Figure 14 in, the damage distribution of the original scheme is on the left, and the loss distribution of the optimal optimization scheme for portal-shaped steel bars is on the right.

[0059] The optimal optimization scheme for portal-shaped steel bars can effectively inhibit the expansion of interface damage and significantly improve the durability of the track structure by reasonably adjusting the layout and spacing of portal-shaped steel bars while ensuring economy. In previous studies, methods such as implanting steel bars and using interface adhesives were used to repair the already generated interface damage, without considering changing the distribution of some structures such as portal-shaped steel bars to inhibit the generation of damage.

[0060] In summary, the optimized method for portal-shaped steel bars based on the analysis of ballastless track interface damage not only establishes an accurate simulation model of the track structure through finite element analysis, but also develops an optimized design method in combination with actual working conditions, realizing the systematic optimization of the layout, size, and reinforcement ratio of portal-shaped steel bars. This method can provide an efficient analysis tool for designers to predict in advance the interface damage risk of ballastless tracks under complex working conditions, facilitating simulation and optimized design before track construction, thereby improving the structural performance in advance. By applying this method, the occurrence probability of interface damage can be significantly reduced. The optimized design scheme reduces interface damage by more than 60%, while the total amount of portal-shaped steel bars only increases by 27.4%. In addition, the stress distribution at the interface between the track slab and the self-compacting concrete filling layer can be comprehensively observed, and the interface stress concentration problem can be analyzed and improved in advance, effectively preventing safety hazards such as track slab debonding and crack propagation caused by interface damage, thereby extending the service life of the track structure and reducing maintenance costs. The research results have important guiding significance for the optimized design and performance improvement of high-speed railway ballastless tracks.

[0061] Figure 15 is a schematic diagram of the modules of the optimized system for portal-shaped steel bars based on the analysis of ballastless track interface damage shown in some embodiments of this specification. As Figure 15 shown, the optimized system for portal-shaped steel bars based on the analysis of ballastless track interface damage may include a parameter determination module, a model establishment module, a shrinkage simulation module, a scheme determination module, a scheme analysis module, and a scheme screening module.

[0062] The parameter determination module is used to determine the interlayer bonding parameters of the ballastless track based on the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimens of the ballastless track. The model establishment module is used to establish a finite element model of the ballastless track based on the original design data of the portal-shaped steel bars of the ballastless track and the interlayer bonding parameters. The shrinkage simulation module is used to calculate the service temperature field of the ballastless track and complete the equivalent simulation of concrete shrinkage. The scheme determination module determines multiple optimized schemes for portal-shaped steel bars based on multiple structural optimization variables. The scheme analysis module is used for each optimized scheme of the portal-shaped steel bars. Based on the finite element model of the ballastless track, a finite element model of the ballastless track corresponding to the optimized scheme of the portal-shaped steel bars is generated. Using the finite element analysis method based on the finite element model of the ballastless track corresponding to the optimized scheme of the portal-shaped steel bars, calculate the damage area and distribution of the track interface of the ballastless track under the combined action of concrete shrinkage and temperature load. The scheme screening module is used to determine the optimal optimized scheme for portal-shaped steel bars based on the damage area and distribution of the track interface of the ballastless track corresponding to each optimized scheme of the portal-shaped steel bars.

[0063] The portal steel bar optimization system based on the ballastless track interface damage analysis can be used to execute the portal steel bar optimization method based on the ballastless track interface damage analysis, which will not be elaborated here.

[0064] Finally, it should be understood that the embodiments described in this specification are only used to illustrate the principles of the embodiments of this specification. Other variations may also fall within the scope of this specification. Therefore, by way of example and not limitation, alternative configurations of the embodiments of this specification may be regarded as consistent with the teachings of this specification. Accordingly, the embodiments of this specification are not limited to the embodiments explicitly introduced and described in this specification.

Claims

1. An optimized method for portal steel bars based on the analysis of the interface damage of ballastless tracks, characterized in that Including: Based on the test data of the interfacial comprehensive mechanical properties of the concrete material composite specimens for ballastless tracks, determine the bonding parameters between the track layers of the ballastless tracks; Based on the original design data of the portal reinforcement for ballastless tracks and the bonding parameters between the track layers, establish a finite element model of the ballastless tracks; Calculate the service temperature field of the ballastless tracks and complete the equivalent simulation of the shrinkage of the self-compacting concrete layer; Based on multiple structural optimization variables, determine multiple optimized portal reinforcement schemes; For each optimized portal reinforcement scheme, based on the finite element model of the ballastless tracks, generate a finite element model of the ballastless tracks corresponding to the optimized portal reinforcement scheme, and use the finite element analysis method to calculate the damage area and distribution of the track interface of the ballastless tracks under the combined action of the shrinkage of the self-compacting concrete layer and the temperature load based on the finite element model of the ballastless tracks corresponding to the optimized portal reinforcement scheme; Based on the damage area and distribution of the track interface of the ballastless tracks corresponding to each optimized portal reinforcement scheme, determine the optimal optimized portal reinforcement scheme.

2. The optimized method for portal steel bars based on the analysis of the interface damage of ballastless tracks according to claim 1, characterized in that Obtain the test data of the interfacial comprehensive mechanical properties of the concrete material composite specimens for ballastless tracks, including: Conduct an interfacial comprehensive mechanical property test on the concrete material composite specimens for ballastless tracks, where the interfacial comprehensive mechanical property test at least includes a splitting tensile test and a shear slip test; Obtain the test data of the interfacial comprehensive mechanical properties of the concrete material composite specimens for ballastless tracks by combining the strain gauge test technology and the digital image correlation technology.

3. The optimized method for portal steel bars based on the analysis of the interface damage of ballastless tracks according to claim 2, characterized in that, Based on the test data of the interfacial comprehensive mechanical properties of the concrete material composite specimens for ballastless tracks, determine the bonding parameters between the track layers of the ballastless tracks, including: Based on the test data of the interfacial comprehensive mechanical properties of the concrete material composite specimens for ballastless tracks, analyze the damage cracking behavior of the concrete material composite specimens for ballastless tracks during the interfacial comprehensive mechanical property test, and determine the bonding parameters between the track layers of the ballastless tracks.

4. The optimized method for portal steel bars based on the analysis of the interface damage of ballastless tracks according to claim 1, characterized in that Based on the original design data of the portal reinforcement for ballastless tracks and the bonding parameters between the track layers, establish a finite element model of the ballastless tracks, including: Based on the original design data of the portal reinforcement for ballastless tracks, establish models corresponding to multiple components of the ballastless tracks and assign material properties, where the multiple components at least include portal reinforcement and track structure reinforcement; Based on the bonding parameters between the track layers of the ballastless tracks, establish a cohesive force model, and simulate the bonding relationship between the track slab and the self-compacting concrete layer of the ballastless tracks through the cohesive force model; Based on the models corresponding to multiple components of the ballastless tracks and the bonding relationship between the track slab and the self-compacting concrete layer, establish a finite element model of the ballastless tracks.

5. The optimized method for portal steel bars based on the analysis of ballastless track interface damage according to claim 1, characterized in that Calculate the service temperature field of the ballastless tracks, including: Based on the material properties, service environment, meteorological factors, and three heat transfer modes of solar radiation, convective heat transfer, and radiative heat transfer of the ballastless tracks, establish a heat conduction differential equation for the ballastless tracks; Use the integral transform method to solve the heat conduction differential equation of the ballastless tracks to determine the analytical expressions of the temperature fields of each layer structure of the ballastless tracks.

6. The optimized method for portal steel bars based on the analysis of the interface damage of the ballastless track according to claim 5, characterized in that Complete the equivalent simulation of the shrinkage of the self-compacting concrete layer, including: Determine the equivalent maximum temperature drop; Based on the equivalent maximum temperature drop, the service temperature field of the ballastless track, and the finite element model of the ballastless track, the equivalent simulation of the shrinkage of the self-compacting concrete layer is completed.

7. The optimized method for portal steel bars based on the analysis of the interface damage of ballastless tracks according to any one of claims 1-6, characterized in that, Using the finite element analysis method, based on the finite element model of the ballastless track corresponding to the optimized portal reinforcement scheme, calculate the damage area and distribution of the track interface of the ballastless track under the combined action of the shrinkage of the self-compacting concrete layer and the temperature load, including: Determine the target working conditions; Apply the temperature load and shrinkage effect based on the target working conditions; Based on the finite element model of the ballastless track corresponding to the optimized portal reinforcement scheme, calculate the damage area and distribution of the track interface of the ballastless track under the combined action of the shrinkage of the self-compacting concrete layer and the temperature load.

8. The optimized method for portal steel bars based on the analysis of ballastless track interface damage according to any one of claims 1-6, characterized in that Based on multiple structural optimization variables, determine multiple optimized portal reinforcement schemes, including: Taking the distribution position of the portal reinforcement, the spacing between adjacent portal reinforcements, and the transverse span of the portal reinforcement as variables, determine multiple optimized portal reinforcement schemes.

9. The optimized method for portal steel bars based on the analysis of ballastless track interface damage according to claim 8, wherein Based on the damage area and distribution of the track interface of the ballastless track corresponding to each optimized portal reinforcement scheme, determine the optimal optimized portal reinforcement scheme, including: Taking the distribution position of the portal reinforcement as a variable, determine multiple first optimized portal reinforcement schemes; Based on the damage area and distribution of the track interface of the ballastless track corresponding to each first optimized portal reinforcement scheme, determine the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure; According to the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure, taking the spacing between adjacent portal reinforcements as a variable, determine multiple second optimized portal reinforcement schemes; Based on the damage area and distribution of the track interface of the ballastless track corresponding to each second optimized portal reinforcement scheme, determine the optimal spacing between adjacent portal reinforcements; According to the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure and the optimal spacing between adjacent portal reinforcements, taking the transverse span of the portal reinforcement as a variable, determine multiple third optimized portal reinforcement schemes; Based on the damage area and distribution of the track interface of the ballastless track corresponding to each third optimized portal reinforcement scheme, determine the optimal transverse span of the portal reinforcement; Based on the optimal distances of the portal reinforcement longitudinally and transversely from the free edge of the track structure, the optimal spacing between adjacent portal reinforcements, and the optimal transverse span of the portal reinforcement, determine the optimal optimized portal reinforcement scheme.

10. A portal steel bar optimization system based on the analysis of the interface damage of the ballastless track, characterized in that, Apply the optimized portal reinforcement method based on the analysis of the damage of the ballastless track interface described in any one of claims 1-9, including: A parameter determination module for determining the interlayer bonding parameters of the track of the ballastless track based on the test data of the comprehensive mechanical properties of the interface of the concrete material composite specimen of the ballastless track; A model establishment module for establishing a finite element model of the ballastless track based on the original design data of the portal reinforcement of the ballastless track and the interlayer bonding parameters of the track; A shrinkage simulation module for calculating the service temperature field of the ballastless track and completing the equivalent simulation of the concrete shrinkage; A scheme determination module for determining multiple optimized portal reinforcement schemes based on multiple structural optimization variables; The scheme analysis module is used to generate a finite element model of the ballastless track corresponding to each optimized portal-shaped steel bar scheme based on the finite element model of the ballastless track, and calculate the damage area and distribution of the track interface of the ballastless track under the combined action of concrete shrinkage and temperature load by using the finite element analysis method based on the finite element model of the ballastless track corresponding to the optimized portal-shaped steel bar scheme; The scheme screening module is used to determine the optimal optimized portal-shaped steel bar scheme based on the damage area and distribution of the track interface of the ballastless track corresponding to each optimized portal-shaped steel bar scheme.

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