Hybrid Multi-Scale Dynamic Analysis Model of High-Speed Train Impacting Shield Tunnel

Train derailment will cause serious damage to the tunnel structure. Therefore, a hybrid multi-scale dynamic analysis model of train impacting shield tunnel is proposed, which can greatly improve the calculation efficiency under the premise of ensuring the calculation accuracy, so as to reduce the potential risk of rail derailment. Firstly, the conventional non-multi-scale model and two single multi-scale models (the same type of unit coarse-fine mesh coupling multi-scale model and different types of unit shell-body coupling multi-scale model) are set up considering the effect of segment joint. The applicability of the two single multi-scale models is verified by comparing and analyzing the segment static test results of the three models. Then, the two single multi-scale models are combined into a hybrid multi-scale model, which is applied to the dynamic analysis of train impacting shield tunnel and compared with the calculation results of the conventional non-multi-scale model. The results show that under static load, the two single multi-scale models are consistent with the conventional non-multi-scale model in terms of the distribution law of displacement, stress and damage area. The errors of calculated values are within 3.5%, and the calculation time is shortened by about 50%. Under the impact load, the segment displacement and tension and compression damage development law calculated by the hybrid multi-scale model and the conventional non-multi-scale model are consistent. But the calculated values of the hybrid multi-scale model are too large, and the errors of the remaining results are all within 5%, except for the tensile damage area error of 8.56%. The hybrid multi-scale model reduces the calculation time by 62.4% under the premise of ensuring the calculation accuracy, which provides more efficient solutions for similar problems. © 2022, Editorial Department of China Railway Science. All right reserved.