Dynamic Responses Analysis on High Speed Railway Subgrade and Subgrade-bridge Transition

摘要

For roadbed and the transition section easily lead to problems of high -speed railway,dynamic response tests of the high r embankment , low embankments, cuttings, half cutting roadbed and filling and excavation of transition section between bridge r and subgrade are carried out when high — speed train passes. Through analyzing large amounts of data ,the conclusions are r made that dynamic displacement changes of different forms of embankment are not obvious as the train speed , and acceleration r increase significantly with the continuous improvement of train speed. Dynamic response of the cut is greater than that of r the high embankment and half -filled and half-dug embankment, and dynamic response of low embankment is the minimum. In r addition, the dynamic response of filling transition section is significantly larger than the cut transition section. The r main reason is that the construction quality of the filling transition section is difficult to guarantee test by ground r penetrating radar. Moreover,it is also found that the dynamic response of transition section increases with the train speed r improvement. And in a certain distance to the abutment which is 31m in this article,the dynamic response of the transition r section decreases with the increase of the distance from bridge abutment.