考虑土层界面效应的尾矿坝渗流稳定性分析
Analysis on seepage stability of tailings dam considering soil-layer interface effect
谢意 1曹海莹 2周城屹 1刘亮 3王强2
作者信息
- 1. 燕山大学建筑工程与力学学院,河北秦皇岛 066004
- 2. 燕山大学建筑工程与力学学院,河北秦皇岛 066004;燕山大学河北省土木工程绿色建造与智能运维重点实验室,河北秦皇岛 066004
- 3. 河北省地质矿产勘查开发局第八地质大队,河北秦皇岛 066001
- 折叠
摘要
为研究渗流作用下尾矿土土层界面处力学行为对尾矿坝稳定性的影响,以河北省秦皇岛市某尾矿坝为研究对象,通过开展渗流直剪试验及FLAC3D数值建模,得出考虑土层界面效应的尾矿坝安全系数.研究结果表明:渗流状态下,随着水头高度上升,尾矿土抗剪强度下降;土层界面黏聚力呈下降趋势,内摩擦角变化幅度平缓;相同水头高度下,土层界面抗剪强度介于2种土层之间,尾细砂和尾粉质黏土界面黏聚力在多因素耦合作用下进一步降低;与Bishop法相比,考虑土层界面效应的尾矿坝在正常水位和洪水位下得到的安全系数分别下降29.0％,12.1％.研究结果可为多层尾矿土堆积而成的尾矿坝稳定性分析提供技术指导.
Abstract
To investigate the influence of mechanical behavior at the soil-layer interface of tailings soil on the stability of tail-ings dam under the seepage conditions,a tailings dam in Qinhuangdao City,Hebei Province,was taken as the research object,and the safety factor of the tailings dam considering the soil-layer interface effect was derived by carrying out the seepage di-rect shear test and numerical modeling in FLAC3D.The results show that under the seepage conditions,the shear strength of tailings soil decreases as the water head height increases.The cohesive strength of the soil-layer interface decreases,while the variation in the internal friction angle is relatively gentle.At the same water head height,the shear strength of the soil-layer interface lays between those of the two soil layers,the cohesive strength of the soil-layer consisting of tailings fine sand and tailings silty clay is further reduced under multi-factor coupling effect.Compared to the Bishop method,the safety factors of the tailings dam considering the soil-layer interface effect under normal water level and flood conditions decrease by 29.0％and 12.1％,respectively.The research results can provide technical guidance for the stability analysis of tailings dams accu-mulated by multi-layer tailings soil.
关键词
尾矿坝/土层界面效应/渗流稳定性/直剪试验/数值模拟Key words
tailings dam/soil-layer interface effect/seepage stability/direct shear test/numerical simulation引用本文复制引用
基金项目
国家自然科学基金项目(51308486)
中央引导地方科技发展资金项目(236Z5401G)
河北省自然科学基金面上项目(E2020203168)
出版年
2024
NETL
NSTL
万方数据