巴准重载铁路高路堤边坡稳定性分析

Slope Stability Analysis of High Embankment at Ba-quasi Heavy-load Railway

针对巴准重载铁路高路堤,采用三维非线性有限元方法,建立了可考虑重载列车振动荷载作用的高路堤边坡稳定性分析的数值模型。通过引入强度折减系数法,分析了未加固和应用土工格栅加固的高路堤边坡的稳定性,据此考察了格栅长度与间距、边坡高度及路基上部荷载等因素对高路堤边坡稳定性的影响效应。数值模型中,路基土体采用莫尔—库伦弹塑性本构模拟,土工格栅选用线弹性本构模拟;通过计算ZK标准活载及等效土柱高度,换算得到路基上部荷载。研究表明:加固重载铁路高路堤时,土工格栅的应用限制了高路堤边坡的侧向滑动,有效地提高了高路堤边坡的稳定性;格栅增长、路堤高度降低能够提高高路堤边坡的稳定性,而格栅间距增大、路基上部荷载增加将降低高路堤边坡的稳定性。

According to the high embankment structure of the Ba-quasi Heavy-haul Railway, the paper provides a high embankment slope stability analysis numerical model considering Heavy- duty train vibration load with 3-D nonlinear FEM. We study the different stability for unreinforced and reinforced high embankment slope with geotechnical grilling by the strength reduction factor method. Then the effect of the gritting length and spacing, the height of slope and the top load on the subgrade on the slope stability was investigated. In the numerical model, the M-C elastic-plastic constitutive law was applied to the subgrade and the linear elasticity constitutive law was applied to the geotechnical grilling. By calculating the ZK standard live load and equiva- lent soil column height, the research was converted to get subgrade top load. The paper shows that when the heavy-haul railway high embankment is strengthen by geotechnical grilling, it can effectively improve the stability of high embankment slope, because the lateral slip is limited. The longer the geotechnical grilling and the higher the subgrade, the greater the stability of the slope will achieve, however, the longer the geotechnical grilling space and the more the load on the subgrade, the less stability the slope will achieve.