Excessive vibrations inside buildings in the Lihu New Village caused by the Shenzhen Metro Line 2 underground railway were investigated by conducting analyses of the tunnel,the track irregularities,the stiffness of th...Excessive vibrations inside buildings in the Lihu New Village caused by the Shenzhen Metro Line 2 underground railway were investigated by conducting analyses of the tunnel,the track irregularities,the stiffness of the fastening system,and the vibrations of the track system and the building at different speeds.A numerical simulation based on the dynamic coupling theory of the vehicle-track system was used to verify the experimental results.Suitable countermeasures were investigated.The results show that rail corrugation is the primary reason for the excessive vibration,and an increase in the stiffness of the vertical fastening system is the secondary reason.The solution was to eliminate the rail corrugation using rail grinding and decrease the vertical stiffness by changing the fastening system.The results of this study provide references for solving vibration problems caused by rail lines.展开更多
Underground railway vibration source strength is one of the key values used for environmental impact assessment and the evaluation of mitigation measure’s performance.However,currently there is no international stand...Underground railway vibration source strength is one of the key values used for environmental impact assessment and the evaluation of mitigation measure’s performance.However,currently there is no international standard of measuring the underground railway vibration source strength for such purposes.The available local standards and industrial guidelines do not agree on measurement locations as well as the metrics for presenting the source strength.This has caused many confusions.This paper aims to study the suitable measurement location and metrics using the data from a large scale field-testing carried out at the Nanchang underground railway(Metro Line 1,China)in 2017.200 passing trains were recorded during the test at two different sections of the railway line,one with the spring floating slab installed and the other without.Three locations were chosen at each section,including one in the middle of the track and two on the tunnel wall at different heights.Based on the results of statistical analysis,the maximum of z-weighted vertical vibration level(VLzmax)obtained at a lower measurement location on the tunnel wall is the best for representing the underground railway vibration source strength,which is 76.66 dB obtained from this study.展开更多
基金Projects(U1734207,51978585)supported by the National Natural Science Foundation of ChinaProject(2016 YFE 0205200)supported by the National Key Research and Development Program of China。
文摘Excessive vibrations inside buildings in the Lihu New Village caused by the Shenzhen Metro Line 2 underground railway were investigated by conducting analyses of the tunnel,the track irregularities,the stiffness of the fastening system,and the vibrations of the track system and the building at different speeds.A numerical simulation based on the dynamic coupling theory of the vehicle-track system was used to verify the experimental results.Suitable countermeasures were investigated.The results show that rail corrugation is the primary reason for the excessive vibration,and an increase in the stiffness of the vertical fastening system is the secondary reason.The solution was to eliminate the rail corrugation using rail grinding and decrease the vertical stiffness by changing the fastening system.The results of this study provide references for solving vibration problems caused by rail lines.
基金The authors are very grateful for the financial support received from the National Natural Science Foundation of China(Grant Nos.51668020,51878277,51478184).
文摘Underground railway vibration source strength is one of the key values used for environmental impact assessment and the evaluation of mitigation measure’s performance.However,currently there is no international standard of measuring the underground railway vibration source strength for such purposes.The available local standards and industrial guidelines do not agree on measurement locations as well as the metrics for presenting the source strength.This has caused many confusions.This paper aims to study the suitable measurement location and metrics using the data from a large scale field-testing carried out at the Nanchang underground railway(Metro Line 1,China)in 2017.200 passing trains were recorded during the test at two different sections of the railway line,one with the spring floating slab installed and the other without.Three locations were chosen at each section,including one in the middle of the track and two on the tunnel wall at different heights.Based on the results of statistical analysis,the maximum of z-weighted vertical vibration level(VLzmax)obtained at a lower measurement location on the tunnel wall is the best for representing the underground railway vibration source strength,which is 76.66 dB obtained from this study.
