采场残坡积土抗剪强度及边坡时效稳定性研究

Study on Shear Strength of Residual Slope and Aging Stability in Stope

在露天采场边坡后期运行维护中,经过长期的露天开采,形成较大的深凹边坡,原先的岩体逐渐风化为土石料,堆积在边坡上,形成一定厚度的残坡积土层。残坡积土层在宏观时间上表现为欠固结土,强度较弱,易受外界因素影响,其中雨水侵蚀影响较为严重。本次研究以永平铜矿东帮采场边坡的残坡积土不同含水率为主要因素,分别在不同月份时间上采集土样,在不同的含水率时,得出其抗剪强度。然后根据不同季节的抗剪强度,分别研究残坡积土层边坡的时效稳定性。研究得出:残坡积土的抗剪强度随含水率的增加而降低;边坡稳定性因强度不同,时效规律表现为旱季稳定性较雨季好;残坡积土层边坡破坏模式为单台阶向多台阶发展渐进破坏。通过对残坡积土取样和室内试验,研究了永平铜矿东帮采场残坡积土边坡的抗剪强度和边坡时效稳定性规律,为边坡后期安全管理提供依据。

In the late operation and maintenance of open-pit slope,after long-term open-pit mining,a large deep concave slope is formed,and the original rock mass gradually becomes weathered into soil and stone materials,which are accumulated on the slope and form residual slope soil layer of a certain thickness.In macro time,the residual slope soil is less consolidated soil,with weak strength and vulnerable to external factors,among which rain erosion is more serious.In this study,different moisture content of residual slope soil in the east stope slope of Yongping Copper Mine was taken as the main factor.Soil samples were collected in different months and time,and its shear strength was obtained at different moisture content.Then according to the shear strength of different seasons,the aging stability of residual slope is studied respectively.The results show that the shear strength of residual slope soil decreases with the increase of water content.The slope stability is better in dry season than in rainy season due to different strength.The failure mode of residual slope is progressive failure from single step to multistep.Through sampling and laboratory tests,the shear strength and aging stability of residual slope in the east stope of Yongping Copper Mine are studied,which provides a basis for the later safety management of the slope.