降雨及爆破扰动下某露天矿山顺层高陡岩质边坡稳定性的影响及优化

Influence and optimization of the stability of high and steep rock slope in an open pit mine under blasting and rainfall disturbance

通过对某矿山顺层岩质边坡的结构面调查,采用室内力学试验的方法确定边坡的岩体质量,并基于强度折减法和极限平衡法理论,对边坡在降雨及爆破扰动条件下的稳定性进行研究。结果显示:边坡在自重+暴雨工况下,边坡结构面无动力扰动影响,边坡处于稳定状态,该工况下边坡的最大剪应变发生在结构面的最上方,结构面中部的最大剪应力为6.0 mm。在自重+爆破工况下,结构面受到动力扰动的影响,边坡的稳定性受到严重威胁,边坡处于不稳定状态,同时结构面中部剪应变已达110 mm,在此条件下边坡可能会产生滑坡等地质灾害。鉴于此,对该顺层边坡进行了优化设计,设计为开采边坡方向与结构面延伸方向夹角为21.32°,优化后的顺层边坡安全系数显著提升,保证了边坡的稳定性。同时为今后相似矿山的安全设计提供了科学依据。

The rock mass quality of the bedding rock slope in a mine is determined by investigating the structural plane of the bedding rock slope and using the indoor mechanical test method.Based on the strength reduction method and the limit equilibrium method,the stability of the slope under the conditions of rainfall and blasting disturbance is studied.The research results show that the slope is stable without dynamic disturbance of the structural plane under the condition of self weight+rainstorm,at the same time,the maximum shear strain of the slope under this working condition can occur at the top of the structural plane,and the maximum shear stress in the middle of the structural plane is 6.0 mm.Under the dead weight+blasting condition,the structural plane is affected by dynamic disturbance,and the stability of the slope is seriously threatened.The slope is in an unstable state,and the shear strain in the middle of the structural plane has reached 110 mm.Under this condition,the slope may have geological disasters such as landslides.Because of this,the bedding slope has been optimized.The design is that the angle between the mining slope direction and the extension direction of the structural plane is 21.32°.The optimized bedding slope safety factor has been significantly improved,ensuring the stability of the slope.At the same time,it provides a scientific basis for the safety design of similar mines in the future.