岩堆斜坡路基极限填方高度的研究

STUDY ON THE CRITICAL FILL HEIGHT OF SUBGRADE UPON ROCK HEAP SLOPE

以麻柳湾-昭通高速公路为工程背景,研究了岩堆斜坡路基的极限填方高度。针对不同的黏聚力c、内摩擦角φ和坡角α设计了96组方案,利用临界滑动场方法计算了岩堆斜坡上的路基极限填方高度,根据计算结果绘制了便于工程实用的路基极限填方高度H的速查曲线。根据该曲线可以开展如下工作:1)迅速获得已知岩堆斜坡的极限填方高度H,初步判断路基的整体稳定性;2)获得设计填方高度H'下路基填料的若干组最小强度指标,为填料的选择提供指导。研究结果应用于麻柳湾-昭通高速公路项目中,取得了良好的效果,也可为类似工程的初步设计提供简单实用的参考依据。

The critical fill height of subgrade upon rock heap slope was studied based on highway from Maliuwan to Zhaotong. Ninety-six sets of schemes were designed in different cohesion,internal friction angle and slope angle conditions. The critical fill heights of rock heap slopes were calculated using critical slip field method and a series of calculated curves of the critical fill height were presented. According to the curves,the critical fill height of subgrade on rock heap slope can be immediately obtained to judge the global stability of subgrade initially if the strength indexes are known. And several groups of the smallest strength indexes of subgrade materials can also be got by back analysis when the design height of subgrade is decided which can be used to provide guidance for materials choice.The results were applied in the project of highway from Maliuwan to Zhaotong which achieved good effects. And the results can also provide a simple and practical reference for other similar projects.