Method for establishing fastener system in high-speed railway coupling model based on ABAQUS

Abstract

The invention belongs to the technical field of railway engineering computer aided design, and particularly relates to a method for establishing a fastener system in a high-speed railway coupling model based on ABAQUS. In order to realize rapid modeling of the fastener system, the fastener system is established by batch two-point springs / dampers based on the combination of ABAQUS and python languages, according to respective characteristics of two types of software, steel rails and track plate components are established by using the ABAQUS, grid division and node set creation are performed, scripts are written by using python, and the fastener system is established by using the python language. And a script written by python is operated through ABAQUS to realize batch establishment of two-point springs / dampers.

Description

Technical Field

[0001] The present invention belongs to the technical field of computer-aided design for railway engineering, and particularly relates to a method for establishing a fastener system in a high-speed railway coupling model based on ABAQUS. Background Technique

[0002] With the continuous increase in the running speed of trains and the increase in traction weight, the impact loads generated during train operation, including the impact force between the wheel and rail and the interaction force between the track and subgrade, will also increase accordingly. Therefore, high-speed heavy-haul railways have high requirements for the safety, reliability, and low maintenance of tracks and subgrades.

[0003] In the ballastless track system, the vehicle interacts with the track, subgrade, and foundation. The rolling cyclic load of the vehicle directly acts on the rail part of the track subsystem. The shape limitation and shock absorption of the rail are borne by the fastener system, and the lower track slab is a rigid concrete structure that does not absorb shocks. Therefore, in order to truly restore the operating service environment of the vehicle, it is particularly important to quickly model the fastener system in the high-speed railway coupling model. Summary of the Invention

[0004] The present invention provides a method for establishing a fastener system in a high-speed railway coupling model based on ABAQUS. Based on the CRTS I type slab ballastless track structure, the finite element simulation software ABAQUS and the python language are used together to complete the establishment of the fastener system in the high-speed railway coupling model, and other parts of the high-speed railway coupling model are realized through the ABAQUS finite element software.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a method for establishing a fastener system in a high-speed railway coupling model based on ABAQUS, including the following steps:

[0007] Step 1, combining the structural characteristics of the actual rail transit system, using the ABAQUS software to establish a finite element model of the rail and the track slab;

[0008] Step 2, in the established finite element model, perform mesh division on the finite element model, establish a node set for the assembly model, name the node set, and use python to realize the acquisition of the input spring-related parameters;

[0009] Step 3, realize obtaining the existing finite element model and node set in python, and write a script;

[0010] Step 4: Open the established finite element model in ABAQUS software, select the written script and run it to achieve batch connection of springs / dampers, and then establish the fastener system.

[0011] Furthermore, when performing the mesh division in Step 2, ensure that there are corresponding nodes between the rail and the track slab in the vertical direction, and require the coordinates to be consistent in the horizontal and vertical directions.

[0012] Furthermore, in Step 3, write a script to make the naming of the finite element model and the naming of the node set correspond to the names in the script.

[0013] Furthermore, in Step 4, open the established finite element model in ABAQUS software, select the written script and run it to achieve batch connection of springs / dampers, and then establish the fastener system. Specifically:

[0014] Open the established finite element model in ABAQUS software, click RunScript under the File toolbar to open the written script file and run it. When running, two windows will pop up. Write the axial length of the spring / damper in the first window and write the stiffness of the spring in the second window. Subsequently, the batch connection of batch springs / dampers will be completed. Then, assign the attributes of the corresponding fasteners to the batch-connected springs / dampers to complete the establishment of the fastener system.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] The fastener system of the present invention is based on the joint implementation of ABAQUS and Python language to batch establish two-point springs / dampers. According to the respective characteristics of the two software, use ABAQUS to establish rail and track slab components, and perform mesh division and node set creation. Use Python to write a script, and run the script written in Python through ABAQUS to batch establish two-point springs / dampers. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a flowchart of the method of the present invention;

[0018] Figure 2 is a schematic diagram of the high-speed railway coupling model of the present invention;

[0019] Figure 3 is a schematic diagram of the obtained axial length of the spring / damper when using the script in ABAQUS of the present invention;

[0020] Figure 4 is a schematic diagram of the obtained stiffness of the spring / damper when using the script in ABAQUS of the present invention;

[0021] Figure 5 Schematic diagram for modifying spring / damper parameters in the ABAQUS software of the present invention;

[0022] Figure 6 Vertical displacement diagram of the rail top surface. Specific implementation manner

[0023] In order to further elaborate the technical solution of the present invention, the present invention will be further described below through embodiments.

[0024] As Figure 1 shown, the method for establishing a fastener system in a high-speed railway coupling model based on ABAQUS in this embodiment includes the following steps:

[0025] Step 1, in combination with the structural characteristics of the actual rail transit system, use the ABAQUS software to establish a finite element model of the rail and the track slab;

[0026] Step 2, in the established finite element model, perform mesh division on the finite element model, establish a node set for the assembly model, name the node set, and use python to realize the acquisition of the input spring-related parameters; when performing the mesh division, ensure that the rail and the track slab have corresponding nodes in the vertical direction, and require the coordinates to be consistent in the horizontal and vertical directions;

[0027] Step 3, in python, realize obtaining the existing finite element model and node set, and write a script, and write the script so that the name of the finite element model and the name of the node set correspond to the names in the script;

[0028] Step 4, open the established finite element model in the ABAQUS software, select the written script and run it to realize the batch connection of the spring / damper, and then realize the establishment of the fastener system. Specifically:

[0029] Open the established finite element model in the ABAQUS software, click RunScript under the File toolbar, open the written script file and run it. When running, two windows will pop up. Write the axial length of the spring / damper in the first window and write the stiffness of the spring in the second window. Subsequently, the batch connection of the batch spring / damper will be completed, and then the attributes of the corresponding fasteners will be assigned to the batch-connected spring / damper to complete the establishment of the fastener system.

[0030] It should be noted that the high-speed railway coupling model such as Figure 2As shown in the figure, from top to bottom are the rail, fastener system (clip and tie plate), track slab, CA mortar layer, base slab, asphalt concrete waterproof layer, subgrade surface layer, subgrade base layer, embankment, bedding course, CFG pile soil and bearing stratum. From the perspective of load transfer, the tie plate of the rail and fastener system can be regarded as a stiffness-damping coupling beam, and the track slab, CA mortar layer, base slab, asphalt concrete layer, subgrade surface layer, subgrade base layer and embankment are regarded as elastic layer elements respectively. For the lowest bedding course, pile and bearing stratum, since the force they receive is small and they are not affected by large geological changes, they can be regarded as an infinite elastic body.

[0031] In the high-speed railway coupling model, except for the fastener system, the rest of the parts are established by ABAQUS. When establishing the fastener system, it is simulated by two-point springs / dampers. The establishment of two-point springs / dampers is in the ABAQUS interaction module. Find the special settings in the menu bar to find the settings of springs / dampers. Each spring / damper is established by manually selecting points. In order to establish two-point springs / dampers in batches more quickly and accurately, a Python script is used to achieve this. The specific code is as follows:

[0032]

[0033]

[0034] In this section of code, #-*-coding:UFT-8-*- is used to specify that the encoding format of the Python source file is UTF-8 to ensure that Unicode characters can be processed correctly; session.journalOptions.setValues(replayGeometry=COORDINATE, recoverGeometry=COORDINATE) is used to set the journal options of ABAQUS to specify the coordinate options for replaying and recovering the geometry; from math import * means importing the math module of Python, which provides some mathematical functions; from abaqus import * means importing all functions and classes of ABAQUS for use in the script; from abaqusConstants import * means importing the constants of ABAQUS for use in the script; from caeModules import * means importing the CAE module of ABAQUS for finite element modeling and post-processing; from driverUtils import executeOnCaeStartup means importing the executeOnCaeStartup function, which is used to perform specific operations when CAE starts up; executeOnCaeStartup() means calling the executeOnCaeStartup function, which will be executed when CAE starts up.

[0035] assembly = mdb.models["Model-1"].rootAssembly

[0036] nodes1 = assembly.sets["Set-1"].nodes

[0037] nodes2 = assembly.sets["Set-2"].nodes

[0038] In this section of code, assembly = mdb.models["Model-1"].rootAssembly means obtaining the assembly model named "Model-1"; nodes1 = assembly.sets["Set-1"].nodes means obtaining the node set named "Set-1" in the assembly; nodes2 = assembly.sets["Set-2"].nodes means obtaining the node set named "Set-2" in the assembly.

[0039] LENGTH = float(getInput('Input the length of spring:'))

[0040] This code represents obtaining the axial length of the spring by inputting in a pop-up window. The pop-up window is as Figure 3 shown.

[0041] Spring stiffness = float(getInput('Input the Spring stiffness of spring:'))

[0042] This code represents obtaining the stiffness of the spring by inputting in a pop-up window. The pop-up window is as Figure 4 shown.

[0043]

[0044] In this section of code, a = mdb.models['Model-1'].rootAssembly represents obtaining the assembly model named "Model-1"; n1 = assembly.sets["Set-1"].nodes represents obtaining the node set named "Set-1" in the assembly; list1 indicates that this list is used to store the coordinate information of the node set "Set-1".

[0045]

[0046] In this section of code, a = mdb.models['Model-1'].rootAssembly represents obtaining the assembly model named "Model-1"; n2 = assembly.sets["Set-2"].nodes represents obtaining the node set named "Set-2" in the assembly; list2 indicates that this list is used to store the coordinate information of the node set "Set-2".

[0047]

[0048] In this section of code, list3 indicates that this list is used to judge and store the node pairs that meet certain conditions in the node sets "Set-1" and "Set-2" in the assembly named "Model-1".

[0049]

[0050] In this section of code, list4 indicates that this list is used to store the regional information corresponding to the node pairs that meet the conditions in the node set "Set-1" in the assembly named "Model-1".

[0051]

[0052] In this section of code, list5 represents that this list is used to store the regional information corresponding to the node pair conditions in the node set named "Set-2" in the assembly named "Model-1".

[0053] final_list = []

[0054] for jj in range(num_3):

[0055] final_list.append((list4[jj], list5[jj]))

[0056] In this section of code, final_list represents that this list is used to store the final node region pairs.

[0057] region = final_list

[0058] In this section of code, region represents creating node region pairs using final_list.

[0059]

[0060] ngs / Dashpot-1']

[0061] This section of code represents creating spring and damper models using the node region pairs, as Figure 5 shown, and naming them 'Springs / Dashpot-1'.

[0062] print('Done')

[0063] This code outputs 'Done', indicating that the task is completed.

[0064] After running this code, it is possible to batch-create springs / dampers to simulate the fastening system. For the created springs / dampers, in the ABAQUS Interaction module, find the Interaction module in the menu bar, open the Spring / Damper Manager, as Figure 5 shown, where the stiffness, damping, and direction of the springs / dampers can be modified.

[0065] After the fastening system is added, a moving load with an axle load of 85 kN and a speed of 350 km / h is applied to the top surface of the rail to complete the calculation. The vertical displacement of the top surface of the rail is as Figure 6 shown, and it can be seen that the vertical displacement of the rail is less than the reference value of the vertical displacement of the rail.

[0066] The main features and advantages of the present invention have been shown and described above. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and without departing from the spirit or basic features of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes falling within the meaning and scope of the equivalent elements of the claims in the present invention.

[0067] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for establishing a fastener system in a high-speed railway coupling model based on ABAQUS, characterized in that It includes the following steps: Step 1: Based on the structural characteristics of the actual rail transit system, use ABAQUS software to establish a finite element model of the rail and the track slab; Step 2: In the established finite element model, perform mesh division on the finite element model, complete the establishment of the node set for the assembly model, name the node set, and use Python to achieve the acquisition of the input spring-related parameters; Step 3: In Python, achieve obtaining the existing finite element model and node set, and write a script; Step 4: Open the established finite element model in ABAQUS software, select the written script and run it to achieve the batch connection of springs / dampers, and then achieve the establishment of the fastener system.

2. The method for establishing a fastener system in a high-speed railway coupling model based on ABAQUS according to claim 1, wherein When performing the mesh division in Step 2, ensure that there are corresponding nodes between the rail and the track slab in the vertical direction, and require the coordinates to be consistent in the horizontal and vertical directions.

3. The method for establishing a fastener system in a high-speed railway coupling model based on ABAQUS according to claim 1, characterized in that In Step 3, write a script to make the naming of the finite element model and the naming of the node set correspond to the names in the script.

4. The method for establishing a fastener system in a high-speed railway coupling model based on ABAQUS according to claim 1, wherein In Step 4, open the established finite element model in ABAQUS software, select the written script and run it to achieve the batch connection of springs / dampers, and then achieve the establishment of the fastener system. Specifically: Open the established finite element model in ABAQUS software, click Run Script under the File toolbar, open the written script file and run it. When running, two windows will pop up. Write the axial length of the spring / damper in the first window and write the stiffness of the spring in the second window. Subsequently, the batch connection of the batch springs / dampers will be completed, and then the attributes of the corresponding fasteners will be assigned to the batch-connected springs / dampers to complete the establishment of the fastener system.

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