摘要
通过沪宁线提速路基的现场动态试验,在实测轨道不平顺、车速为120-200 km·h^-1情况下,采用动力有限元方法计算铁路路基的动力响应。分析路基动应力的分布形式、路基动应力随列车速度的变化规律、路基动应力随深度的衰减规律,以及道床厚度、路堤高度对路基动应力影响规律。研究表明：路基动应力随列车速度的提高而呈线性增加;路基动应力总体上呈双峰的马鞍型分布,且随着路基深度增加,双峰的幅度减小,直至双峰消失,变为路基中心动应力最大的单峰型;随道床厚度的增加,路基竖向动应力显著减小;路堤高度的增加对路基动应力的影响不大,但可有效减小地基表面的动应力。
According to dynamic finite element method and field dynamic test on Shanghai--Nanjing main line subgrade under track irregularities and train speed 120--200 km·h^-1, the study about the dynamic response of the speed-increase subgrade on existing railway is carried out. Distribution of dynamic stress on the base surface, the relationship between dynamic stress of the subgrade and train speed, the degradation laws of dynamic stress along the depth are obtained. The influence of the thickness of road bed and height of subgrade are analyzed for the dynamic stress. Results show that the dynamic stress of the subgrade linearly increased with speed-raising of the train. The dynamic stress on the subgrade appeared saddle distribution with double hump and with the depth increasing the peak of the saddle will decrease till the dynamic stress at the center of subgrade became single-hump distribution. With road bed thickness increasing, the vertical dynamic stress of the subgrade surface will be obviously reduced. The influences of subgrade height are not great to the dynamic stress of the subgrade surface, but the dynamic stress of the foundation surface can be effectively reduced.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2007年第4期7-11,共5页
China Railway Science
关键词
路基
动力有限元
动力响应
既有线提速
Subgrade
Dynamic finite element
Dynamic response
Speed-increase of existing railway
