Experimental research on dynamic response characteristics of transition subgrade induced by heavy-haul trains
Nie Rusong1,2 Mei Huihao1 Leng Wuming1,2 Zhao Chunyan1,2 Li Yafeng1 Tu Renpan1
1. School of Civil Engineering, Central South University, Changsha 410075, China;
2. The Key Laboratory Heavy-haul Railway Engineering Structures of the Ministry of Education, Central South University, Changsha 410075, China
Abstract：The dynamic responses of subgrade under moving train loads can provide reference for subgrade settlement prediction, condition evaluation and so forth. The field dynamic tests were conducted on transition subgrade in Shuo-Huang heavy-haul railway in China. The variation rules of peak dynamic displacements along the track and the subgrade slope were analyzed, and the random distribution characteristics of the peak dynamic displacements at subgrade shoulder were studied. The response characteristics of subgrade during the train passage were investigated, and the attenuation regularities of vibration along the subgrade slope were revealed. The results indicate that the action of train moving loads on subgrade has obvious periodicity, and two bogies in the adjacent wagons can be regarded as one loading unit. The peak dynamic displacements at the subgrade shoulder obey normal distribution under the repeated loading of the loading units. The vibration frequency mainly distributes between 0 and 20Hz under the loading of heavy-haul trains. The vibration energy attenuates severely from the subgrade shoulder to the slope toe. The subgrade bed is influenced dramatically by dynamic loadings of trains, and moving train loads have little influence on the part below the subgrade bed. The research results can provide basis for the evaluation of instantaneous and long-term dynamic stability of subgrade, and offer guidance for simulating the train moving loads precisely in model test and numerical analysis to study the dynamic response of subgrade.
聂如松 梅慧浩 冷伍明 赵春彦 李亚峰 涂仁盼. 重载铁路过渡段路基动力响应特性试验研究#br#[J]. 土木工程学报, 2019, 52(5): 101-115.
Nie Rusong Mei Huihao Leng Wuming Zhao Chunyan Li Yafeng Tu Renpan. Experimental research on dynamic response characteristics of transition subgrade induced by heavy-haul trains. 土木工程学报, 2019, 52(5): 101-115.
