磷矿层状边坡变形失稳的灾变分析

以云南磷化集团有限公司尖山磷矿为工程背景，依据其陡倾层状斜坡变形失稳特征，采用尖点突模型分析了斜坡失稳的演化过程和内在控制因素，并结合层状岩体受力分析特点，对露天矿边坡开挖稳定性进行了研究。结果表明：①岩层厚度的增加可提高岩体的抗弯刚度，能有效控制边坡溃屈破坏的发生。采用岩土体锚固技术或分级顺层清方可降低该类边坡失稳的风险。②当斜坡岩层厚度一定时，斜坡的临界坡长随着岩层倾角的增大呈减小趋势，且岩层厚度越大，该递减的趋势越加显著；当岩层倾角一定时，斜坡的临界坡长随着岩层厚度的增加呈增大趋势，且岩层倾角的增大，该增大的幅度减小，同时，当岩层倾角大于40°时，随岩层厚度增加而致使斜坡临界坡长增大的幅度趋于一致。相关的研究成果可为该矿或类似条件下的露天采场运输工艺提供理论和技术上的指导和建议。

Disaster Analysis of the Deformation and Instability of Phosphate Rock Bedded Slope

With the Jianshan Phosphate Mine in Yunnan Phosphate Chemical Group Limited Company engineering back-ground,and in terms of the deformation and instability characteristics of stratified steep dip rock slope, the slope instability process and intrinsic controlling factor have been analyzed by using the cusp catastrophe model. The excavation stability of open-pit slope has been researched with respect to the stress state of the stratified rock slope. The results show as following:(1)With the thickness of strata increasing,lithodeme flexural strength of rock would increase,which could effectively control and prevent from the turn sand twists failure. The rock-soil anchor technology or the step bedding cleaning could reduce risk of this kind of slope instability. (2)With the thickness of bedding slope fixed,the critical slope length would show downward trend with the increase of strata inclination. The thicker the thickness is,the severer the trend becomes. If the inclination is fixed,the critical slope length would show upward trend with the increase of strata thickness. The higher the inclination is,the lower the amplitude becomes. Meanwhile,if the strata inclination is higher than forty degrees,critical slope length increasing amplitude caused by the thicker thickness of strata tends to coincide. The relevant research results provide theoretical and technical guid-ance and advice for the open pit transportation technology of the mine or mining area with similar conditions.