【摘要】 降雨是诱发尾矿坝失稳溃决的主要致灾因素之一，为探究降雨强度与持续时间对尾矿坝渗流演化及稳定性的影响权重，以内蒙古赤峰某典型尾矿库为研究对象，基于MIDAS GTS NX平台构建了能够反映尾矿坝坝体分层结构和岩体特性的三维有限元模型。通过设计对比降雨时长恒定下的降雨强度梯度变化（10～200 mm/d）和降雨强度恒定下的降雨时长梯度变化，系统揭示了2种降雨模式下尾矿坝渗流场动态响应规律及稳定性劣化机制。研究表明：在等效降雨量条件下，降雨强度对坝体稳定性的控制效应显著强于降雨持续时间。具体而言，高降雨强度（>200 mm/d）将导致浸润线急剧抬升，渗透流速峰值增幅达354.23%，同时诱发最大剪应变集中区域逐渐从尾矿堆积坝向初期坝迁移，致使安全系数下降，显著加剧渗透破坏风险；而降雨持续时间延长虽会引起孔隙水压力梯度缓变与浸润面滞后抬升，但对渗流场扰动幅度及稳定性折减率均呈现弱敏感性。研究结果定量揭示了降雨参数对尾矿坝灾变进程的差异化影响规律，可为降雨下的尾矿库风险预警与防控决策提供理论依据。更多还原

【Abstract】 Rainfall is one of the main disaster-causing factors that induce the instability and failure of tailings dams. To explore the influence weights of rainfall intensity and duration on the seepage evolution and stability of tailings dams,taking a typical tailings dams in Chifeng,Inner Mongolia as the research object,a 3D finite element model that can reflect the stratified structure and rock mass characteristics of the tailings dam body was constructed based on the MIDAS GTS NX platform. By designing and comparing the gradient changes of rainfall intensity(10～200 mm/d)and rainfall duration under constant rainfall intensity,the dynamic response laws and stability deterioration mechanisms of the seepage field of tailings dams under the 2 rainfall modes were systematically revealed. Research shows that under the condition of equivalent rainfall,the control effect of rainfall intensity on the stability of the dam body is significantly stronger than that of rainfall duration. Specifically,high rainfall intensity(>200 mm/d)will cause a sharp rise in the infiltration line,with the peak infiltration flow velocity increasing by 354.23%. At the same time,it will induce the concentrated area of maximum shear strain to gradually shift from the tailings accumulation dam to the initial dam,resulting in a decrease in the safety factor and significantly increasing the risk of infiltration damage. Although the prolonged duration of rainfall can cause a gradual change in the pore water pressure gradient and a lagging rise in the infiltration surface,it shows weak sensitivity to the disturbance amplitude and stability reduction rate of the seepage field. The research results quantitatively reveal the differentiated influence laws of rainfall parameters on the disaster process of tailings dams,which can provide a theoretical basis for the risk early warning and prevention and control decision-making of tailings dams under rainfall.更多还原