基于渗流分析的砭家沟尾矿库坝体稳定性研究

Study on Dam Stability of Bianjiagou Tailings Dam based on Seepage Analysis

为了确保砭家沟尾矿库的安全运行,通过现场勘查,建立了正常水位、洪水水位与特殊水位工况下的尾矿库有限元分析模型,对尾矿库的渗流特性及稳定性进行研究。研究结果表明,浸润线的高度随着库区内水位的抬升而逐步抬升,正常水位与洪水水位工况下,浸润线没有从坝坡逸出,不会发生渗流破坏;采用Bishop法与瑞典圆弧法对坝体稳定性进行分析,滑移面的起始滑移点会随着库区内水位的升高而抬升,正常水位与洪水水位工况下均能保证滑移要求,但洪水水位的相对安全系数较小,特殊水位工况下,会造成滑移失稳破坏;在后期的运行过程中,需要增加对外来水流的引导及内部水流的疏散,确保尾矿库的安全运行。

In order to ensure the safe operation of Bianjiagou tailings dam,the finite element analysis models under normal water level,flood water level and special water level were established through field exploration,so as to study its seepage characteristics and stability.The results showed that the height of the infiltration line was gradually raised with the uplift of the water level in the dam area.Under the normal water level and the flood water level,the infiltration line did not escape from the dam slope,and the seepage failure would not occur.The stability of the dam body was analyzed with the Bishop method and the Swedish arc method.The starting slip point of the slip surface would elevate with the rise of the water level in the dam area.The slip requirements could be ensured under the normal water level and the flood water level.But the relative safety coefficient of the flood water level was small,and the slip instability would be caused under special water level.During the later stage of operation,it was necessary to increase the guidance of external water flow and the evacuation of internal water flow,so as to ensure the safe operation of the tailings dam.