深凹露天矿边坡稳定的空间受力状态分析

MECHANICAL ANALYSIS ON THE STABILITY OF DEEP FURROW PIT SLOPE

在假定岩体为连续、均质、各向同性的弹性体,只承受自重应力和进行倒截头圆锥形开挖情况下,运用弹性力学原理对深凹露天矿边坡的空间效应进行分析,并推导出边坡环形岩石的临界滑动角α与岩石容重γ、摩擦系数f、岩石的环向弹性模量E_θ和开挖半径r之间的关系式。该式表明临界滑动角随着开挖深度的增加而增加的空间力学原理,它为深凹露天矿采用可减少下部废石剥离量或减小剥采比的凸曲线形边坡奠定了理论基础,也为确定其边坡的合理形状提供了初步方法。本理论包含了传统边坡稳定性分析的原理,并适用于其他岩石深凹边坡开挖工程的稳定性分析。凸曲线形边坡的采用将会带来巨大的经济效益。

The space effect of the furrow pit slope is analysed by elastic mechanics principle. The relation formula among the critical slide angle, the friction coefficient, the elastical modulus in circular direction of the circular rock, and the horizontal radius of the furrow pit is derived under the conditions, in which the rock mass is homogeneous and elastic, and loaded only by its dead weight and excavated like the reverse frustum. The relation formula shows that the deeper the furrow pit is excavated, the greater the critical slide angle is. Based on the relation formula both the theoretical basis for reducing stripping in furrow pits and the basic way to determine the figure of the stable slope are developed. The theory not only includes the conventionl principles for analysing the stability of slopes but also is available for analysing the stability of furrow pits. The great economic efficiency may be obtained by using the camber curve as the figure of furrow pits.