不同降雨量对尾矿坝稳定性的影响规律分析

Influence Law Analysis of Different Precipitation to the Stability of Tailings Dam

降雨量的多少会影响尾矿坝的浸润线,尾矿坝浸润线的高低也是影响其稳定性的主要指标之一,因此研究尾矿坝稳定性就应该在研究浸润线影响的同时研究降雨量对尾矿坝稳定性的影响。在考虑尾矿坝原有浸润线的基础上,分别对2个尾矿坝剖面在正常水位、20 a一遇24 h最大降雨量、50 a一遇24 h最大降雨量和100 a一遇24h最大降雨量的4种不同降雨工况下,采用极限平衡法中的瑞典圆弧法、毕肖普法和简布法3种不同的计算方法与渗流同步计算尾矿坝的稳定性,得出尾矿坝的最小安全系数与降雨量呈线性相关的关系,降雨量越大,尾矿坝最小安全系数就越小,尾矿坝越不稳定;尾矿坝面积越大,受降雨影响越大。

As rainfall usually influences saturation line of tailing dam,and saturation line is one of the main factors to affect the stability of the tailing dam. Therefore,to study the stability of tailing dam,the influences of saturation line and precipitation should also be investigated. Based on the saturation line of tailing dam,under four different rainfall modes of the normal water level,5% frequency maximum rainfall in 24 h,2% frequency maximum rainfall in 24 h,1% frequency maximum rainfall in 24 h,three kinds of calculation methods including Sweden arc method,Bishop method,and Janbu belonging to the limit equilibrium method,associated with seep synchronous computation,were employed to analyze the stability of tailing dam. It is revealed that minimum safety coefficient has a linear correlation with precipitation. The greater the rainfall,the less the minimum safety coefficient,and the more unstable tailing dam is. Also,the greater the tailing dam area,the greater the influence of rainfall is.