On use of the hierarchical function to achieve efficient and accurate dynamic analysis of vehicle-slab track coupled systems

Abstract To improve the accuracy and efficiency of the vehicle-track dynamic interaction under the framework of traditional finite element method, the hierarchical function has been introduced into the track structure modeling and coupled by multi-scale coupling method in substructural interaction and wheel–rail contacts with high modeling versatility. The reliability of the proposed method is validated by comparing to the results obtained by the FEM model from aspects of the dynamic response in the time- and frequency-domain and the characteristic frequencies of structural vibration. In addition, the efficiency and accuracy of hierarchical function in vehicle–track dynamics simulation are also proved. In the numerical examples, the errors of FEM-based and hierarchical function-based track structure models are analyzed from the perspective of characteristic frequency; the computational efficiency and accuracy of different hierarchical function-based coupled dynamics models of vehicle-track are compared; finally, the shear effect of rails and track slabs on the dynamic response of the system is analyzed. Numerical analysis indicated that, in comparison with other high-order function, the calculation efficiency can be increased by 56%. Furthermore, the shear effect predominantly influences vertical dynamic response, but has little effect on displacement and lateral dynamic response.