【摘要】 采用动力非线性有限元法,分析了尾矿坝地震反应、超孔隙水压力的发展过程和变形特征,研究了土工织物减小尾矿坝地震变形的效果。分析结果表明,坝顶加速度峰值相对于输入加速度峰值放大1.4倍,地震变形主要集中于下游坡。坝体中超孔隙水压力开始时段迅速增大,随后趋向平稳。从坝坡表面往下,超孔隙水压力比逐渐减小,且上游坡的超孔隙水压力比大于下游坡的。下游坡子坝区铺设土工织物有效地减小了坝体地震变形。最后提出了一种尾矿坝综合抗震措施,即在子坝区铺设土工织物,初期坝外坡施加反压体,初期坝坝基易液化土层被夯实,计算结果说明综合抗震措施起到了较好的抗震效果,可为尾矿坝抗震设计提供参考。更多还原

【Abstract】 Earthquake response of tailings dam,development of excess pore water pressure and deformation features were analyzed by using dynamic nonlinear finite element method,the effect of geotextile to reduce the deformation of dam due to earthquake was studied.Result shows that seismic deformation mostly focused on downstream slope as the acceleration peak value at the crest of dam is magnified 1.4 times of that at the toe of dam.Excess pore water pressure in the dam body increased quickly at the beginning and then tended to be stable.From the slope down to depth,excess pore water pressure ratio gradually reduced,and the excess pore water pressure ratio at the upstream slope is bigger than that at the downstream slope.Paving geotextile in downstream slope of subdam effectively mitigated the seismic deformation.Finally,a synthetical antiseismic measure is proposed for tailings dam,with subdam being reinforced with geotextile and outer slop of initial dam being exerted pressure and the liquefied soil layer of initial dam being compacted.It is found that the synthetically antiseismic measure produces better effect,and also can be taken as reference for the seismic design of tailings dam.更多还原