陡坡地基上高填路堤极限承载力研究

Study of the ultimate capacity of embankments on mountain steep slope foundation

结合山区高速公路建设的实践,采用大型室内模型试验,找出了荷载作用下陡坡地基上高填方路堤滑动破坏面出现的位置及形态。通过对路堤边坡稳定性计算的极限分析上限法进行研究,根据折线形滑动面形式建立机动容许速度场,推导计算斜坡地基上高填方路堤稳定性及极限承载力的计算公式。运用此方法对斜坡地基上不同斜坡坡度、不同填土高度、不同路堤宽度以及不同路堤边坡坡度的填方路堤极限承载力进行计算,得出各个因素对其极限承载力的影响。研究结果表明:路堤填筑高度和顶面宽度对其极限承载力的影响最大,其次为斜坡坡度的影响,而路堤边坡坡度对其影响并不显著。建议在斜坡地基上填方路堤的设计与施工过程中综合考虑斜坡坡度、填土高度、路堤宽度、路堤边坡坡度、极限承载力等各种因素的影响,以确保山区高速公路安全畅通。

According to practices experiences in the expressway construction on the mountain region, full scale model experiment was carried. The form and position of the slip curve surface of embankments on steep slope foundations were found by full scale model experiment. The computing method for the stability analysis of embankments on mountain slope foundation was studied. The upper - bound theorem of limit analysis for such slopes was developed, and the slid face＇ s velocity field of folding line was established. The primary factors analyses for the ultimate capacity of embankments on mountain slope foundation include the slope foundation＇ s grade and the height of the embankments and the width of the embankments and the slope＇ s grade of embankments. According to practices experiences in the expressway construction on the mountain region, the effect of some primary factors for the ultimate capacity of embankments on mountain slope foundation were analyzed by upper - bound theorem of limit analysis, and some useful conclusion were obtained. Furthermore some viewpoints conceming the construction of high embankments on mountain slope foundation were proposed.