DYNAMIC STRESS ANALYSIS OF SUBGRADE-BRIDGE TRANSITION SECTION OF QINSHEN RAILWAY
秦沈客运专线路桥过渡段路基动应力测试分析

The damage of subgrade is made by the high speed train passing roadbed-bridge transition section. Qinshen special rail line for passenger is the first railway which has the capability to run over 160 km/h in our country. The dynamic stress of subgrade-bridge transition section under high-speed train action is analyzed and tested in Qinshen railway from DK46+765.95 to DK46+790.95. The longitudinal distributive regularities of dynamic stress of subgrade-bridge transition section,relationships between train speed and dynamic stress,and variety of dynamic stress with depth are analyzed. The analytical results indicate that the longitudinal distribution of dynamic stress has a tendency to increase with train speed,but when train speed exceeds 176 km/h,dynamic stress increases a little,even decreases slightly. Dynamic stress is attenuated very fast with depth of subgrade,and approaches static stress as depth increases.