Under high-level earthquakes,bridge piers and bearings are prone to be damaged and the elastoplastic state of bridge structural components is easily accessible in the train-track-bridge interaction(TTBI)system.Conside...Under high-level earthquakes,bridge piers and bearings are prone to be damaged and the elastoplastic state of bridge structural components is easily accessible in the train-track-bridge interaction(TTBI)system.Considering the complexity and structural non-linearity of the TTBI system under earthquakes,a single software is not adequate for the coupling analysis.Therefore,in this paper,an interactive method for the TTBI system is proposed by combining the multi-body dynamics software Simpack and the seismic simulation software OpenSees based on the Client-Server architecture,which takes full advantages of the powerful wheel-track contact analysis capabilities of Simpack and the sophisticated nonlinear analysis capabilities of OpenSees.Based on the proposed Simpack and OpenSees co-simulating train-track-bridge(SOTTB)method,a single-span bridge analysis under the earthquake was conducted and the accuracy of co-simulation method was verified by comparing it with results of the finite element model.Finally,the TTBI model is built utilizing the SOTTB method to further discuss the running safety of HST on multi-span simply supported bridges under earthquakes.The results show that the SOTTB method has the advantages of usability,high versatility and accuracy which can be further used to study the running safety of HST under earthquakes with high intensities.展开更多
A high-speed train-track coupling dynamic model is used to investigate the dynamic behavior of a high-speed train operating on a curved track with failed fasteners. The model considers a high-speed train consisting of...A high-speed train-track coupling dynamic model is used to investigate the dynamic behavior of a high-speed train operating on a curved track with failed fasteners. The model considers a high-speed train consisting of eight vehicles coupled with a ballasted track. The vehicle is modeled as a multi-body system, and the rail is modeled with a Timoshenko beam resting on the discrete sleepers. The vehicle model considers the effect of the end connections of the neighboring vehicles on the dynamic behavior. The track model takes into account the lateral, vertical, and torsional deformations of the rails and the effect of the discrete sleeper support on the coupling dynamics of the vehicles and the track. The sleepers are assumed to move backward at a constant speed to simulate the vehicle running along the track at the same speed. The train model couples with the track model by using a Hertzian contact model for the wheel/rail normal force calculation, and the nonlinear creep theory by Shen et al. (1984) is used for wheel/rail tangent force calculation. In the analysis, a curved track of 7000-m radius with failed fasteners is selected, and the effects of train operational speed and the number of failed fasteners on the dynamic behaviors of the train and the track are investigated in detail. Furthermore, the wheel/rail forces and derailment coefficient and the wheelset loading reduction are analyzed when the high-speed train passes over the curved track with the different number of continuously failed fasteners at different operational speeds. Through the detailed numerical analysis, it is found that the high-speed train can operate normally on the curved track of 7000-m radius at the speeds of 200 km/h to 350 km/h.展开更多
基金Project(2020EEEVL0403)supported by the China Earthquake AdministrationProjects(51878674,52022113)supported by the National Natural Science Foundation of ChinaProject(2022ZZTS0670)supported by the Fundamental Research Funds for the Central Universities,China。
文摘Under high-level earthquakes,bridge piers and bearings are prone to be damaged and the elastoplastic state of bridge structural components is easily accessible in the train-track-bridge interaction(TTBI)system.Considering the complexity and structural non-linearity of the TTBI system under earthquakes,a single software is not adequate for the coupling analysis.Therefore,in this paper,an interactive method for the TTBI system is proposed by combining the multi-body dynamics software Simpack and the seismic simulation software OpenSees based on the Client-Server architecture,which takes full advantages of the powerful wheel-track contact analysis capabilities of Simpack and the sophisticated nonlinear analysis capabilities of OpenSees.Based on the proposed Simpack and OpenSees co-simulating train-track-bridge(SOTTB)method,a single-span bridge analysis under the earthquake was conducted and the accuracy of co-simulation method was verified by comparing it with results of the finite element model.Finally,the TTBI model is built utilizing the SOTTB method to further discuss the running safety of HST on multi-span simply supported bridges under earthquakes.The results show that the SOTTB method has the advantages of usability,high versatility and accuracy which can be further used to study the running safety of HST under earthquakes with high intensities.
基金Project supported by the National Natural Science Foundation of China (No. U1134202)the National Basic Research Program (973) of China (No. 2011CB711103)the Program for Changjiang Scholars and Innovative Research Team in University (Nos. IRT1178and SWJTU12ZT01), China
文摘A high-speed train-track coupling dynamic model is used to investigate the dynamic behavior of a high-speed train operating on a curved track with failed fasteners. The model considers a high-speed train consisting of eight vehicles coupled with a ballasted track. The vehicle is modeled as a multi-body system, and the rail is modeled with a Timoshenko beam resting on the discrete sleepers. The vehicle model considers the effect of the end connections of the neighboring vehicles on the dynamic behavior. The track model takes into account the lateral, vertical, and torsional deformations of the rails and the effect of the discrete sleeper support on the coupling dynamics of the vehicles and the track. The sleepers are assumed to move backward at a constant speed to simulate the vehicle running along the track at the same speed. The train model couples with the track model by using a Hertzian contact model for the wheel/rail normal force calculation, and the nonlinear creep theory by Shen et al. (1984) is used for wheel/rail tangent force calculation. In the analysis, a curved track of 7000-m radius with failed fasteners is selected, and the effects of train operational speed and the number of failed fasteners on the dynamic behaviors of the train and the track are investigated in detail. Furthermore, the wheel/rail forces and derailment coefficient and the wheelset loading reduction are analyzed when the high-speed train passes over the curved track with the different number of continuously failed fasteners at different operational speeds. Through the detailed numerical analysis, it is found that the high-speed train can operate normally on the curved track of 7000-m radius at the speeds of 200 km/h to 350 km/h.
