由于场地的惟一可选性,尖山铁矿南排土场布置在软弱黄土斜坡地基上。从2008年开始,先后发生过不同程度的失稳破坏。基于工程类比方法,采用现场勘查、监测和跟踪调查等手段,研究黄土软弱斜坡地基排土场的滑坡孕育演化机制,就其滑坡类型及模式(低速缓动、旋转、牵引式)、成因机制(超载和侧向挤压主导、降雨触发)和孕育演化过程(持力层蠕滑-地基底鼓-黄土梁拉裂-旋转滑动-裂缝扩展-上部坐落)进行分析。从排土场边坡与基底的相互作用特征出发,采用理论分析确定最大堆载高度,基于工程类比和统计分析确定破坏范围,评估失稳对周边环境的影响后果。滑坡孕育演化机制指出,合理使用排土空间、调整排土场生成过程的时空关系、控制排土速度是调控系统各子结构过程稳定性的关键。并提出允许适度破坏的设计理念。
The south waste dump of Jianshan Iron Mine located on weak loess slope foundation due to the unique-selection of the dump site,various degree failures sequentially occurred since 2008.Based on engineering analogism,in-situ investigation,field monitoring and tracking geologic survey technology were used to research the landslide formation evolution mechanism of the waste dumps located on loess foundation,specially the landslide types and failure modes(low-speed and slight-starting,rotational and retrogressive mode),formative mechanism and conditions(overload and lateral compression leading,precipitation trigger),landslide procedure,feature and distribution regulation(supporting course creep-floor heave-loess ridge tensile fracturing-rotational sliding-crack propagation-slip plane-retrogressive fallout).Starting with effect interaction characteristics between the waste dump and the loess slope foundation,the limit height of dumping-site determined by theoretical formula,failure range estimated by engineering analogism and statistical analysis,influence degree on environmental(equipments,human beings,building,etc.) were studied.It was the key countermeasure to adjust and control course safety of substructure,such as intelligently using dumping-site space,adjusting time-space relation during waste dumps emission,controlling emission speed.The conceptual design is submitted that moderately failure should be permited.