高速铁路路基黄土滑移变形的动力数值模拟

Dynamic numerical simulation for slip deformation of loess foundation of highspeed railway

以郑(州)-西(安)高速铁路为例,选择典型路段(华阴、潼关、灵宝和偃师等),采集大量原状黄土样品,进行动三轴试验,获得一系列黄土动力学参数,如动弹模、动阻尼、残余应变等,进而建立高速铁路黄土路基动力学数值模型。按该线路地震危险性分析结果,合成8条人工地震波(50年10%和2%的超越概率水平),输入该动力学模型中进行计算。结果表明:黄土路基的横向和纵向变形都随着地震力的增大而增大,从而导致黄土滑移和震陷,这与现场激振试验及动三轴震陷试验结果基本一致。该结果为郑西高速铁路抗震陷和抗滑移设计提供了重要依据,并提出了切实可行的黄土抗震陷和滑移地基处理措施,已应用于该高速铁路的设计与施工中。

This paper takes Zhengzhou-Xi＇ an highspeed railway （350km/h） as the object of the study, a large number of undisturbed loess samples in Huayin, Tongguan, Lingbao and Yanshi sections have been collected, based on the dynamic triaxial test of those samples, the relevant dynamic parameters of loess such as dynamic elastic modulus, dynamic damp and remains strain were provided. Furthermore, the numerical model of highspeed railway loess foundation is established; eight artificial seismic waves （10% and 2% exceedance probability in 50 years） are made according to the seismic risk analysis results, and then put them into dynamic model to calculate the deformation of loess foundation. The results foundation increase with the earthquake force, agrees with the results of field making-seismic anti-seismic subsidence and anti-slide designs, and used in the design and construction of this show that both the horizontal and vertical deformations of loess ultimately resulting in the slip and seismic subsidence of loess, It test and dynamic triaxial test. The present result is the basis of the and some feasible foundation treatment measures are bring forward highspeed railway.