危岩稳定性计算新体系

A New System of Stability Calculation for Dangerous Rock Mass

地质灾害防治研究中,危岩的研究相对较为薄弱,稳定性计算模型体系不够完善。本文在五个常用计算模型的基础上,增加了后缘有贯通陡倾裂隙的滑移式、双结构面滑移式、后缘无陡倾裂隙且形似悬臂梁的坠落式、上缘岩体抗拉强度控制的坠落式四个新的计算模型,形成了危岩稳定性计算模型新体系。依托工程实例对后缘有贯通陡倾裂隙的滑移式危岩新计算模型的稳定性进行运用验证,即:基于刚体力学的极限平衡法计算求出不同工况下危岩单体的稳定性系数,再基于FLAC3D运用摩尔-库伦模型对该危岩单体进行数值模拟,计算求出其在两种不同工况的稳定系数,两种方法相互印证其可靠性。

In research of geological hazards,less work has been made on dangerous mass,and there is no complete calculation system for rock stability. This work attempts to solve this problem. Based on five common models,we propose four new models which are for distinct slope failures： rock slide from a back scarp with connected steep cracks,rock slide on a double structural surface,rock fall from a back scarp like a cantilever without steep cracks,and rock fall from a upper scarp dependent on tensile strength. These four models constitute a new system for calculation of slope stability. Of them,the first model is verified using a project example. In this case analysis,firstly the stability coefficients of a single rock mass are worked out for different conditions using the limit balance method that is based on mechanics of rigid bodies. Then simulation is performed in terms of FLAC3 D on a Mohr-Coulomb model to calculate the stability coefficients for two conditions. The results from these two approaches are identical,indicating that this model is reliable.