采空区边坡崩滑成因机理研究

The Mechanism of Slope Slump in Goaf

摘要: 随着对地下矿产的开采，采空区边坡地质灾害突发现象日益突出，尤其是崩塌和滑坡造成了重大生命财产损失，近年来引起了广泛的关注。本文以2017年8月28日贵州纳雍县张家湾镇普洒村崩塌滑坡为研究对象，通过现场勘查，对崩滑区的概况有一个初步掌握，深入分析其成因机制，并结合PFC数值模拟，对边坡的崩滑发展过程进行模拟。分析研究认为，该边坡在自然风化作用以及开采作用下，岩体节理裂隙开始发育，由于坡体中部陡缓交界处应力集中，促进坡体局部软岩崩滑，使坡顶岩体开始出现拉裂缝，随着开采的继续，裂隙逐渐贯通，并沿陡倾结构面发展，随着裂隙的发展，坡体顶部危险岩体以崩塌为主，中下部危险岩体以边破碎边滑动的方式沿坡面往下运动，整个边坡破坏由崩塌破坏为主变为滑移破坏为主。研究贵州纳雍县张家湾镇普洒村崩塌滑坡成因机制，对我国山区存在类似条件的灾害隐患点的研究以及未来的减灾防灾工作，具有重要的指导意义。

Abstract: With the exploitation of underground minerals, the phenomenon of slope collapse in gap goaf is becoming more and more prominent. This paper takes the landslide of Pusha Village, Zhangjiawan Town, Nayong County, Guizhou Province, on August 28, 2017 as the research object. Through on-site investigation, the preliminary grasp of the general situation of the landslide area is clear, and its genesis mechanism is analyzed. Combining numerical simulation named PFC2D to the side to simulate the process of slope collapse and landslide, the analysis shows that under natural weathering and mining, joints and fissures begin to develop in the rock mass of the slope. The stress concentration at the steep and gentle junction in the middle of the slope promotes local soft rock collapse and landslide, which makes the rock mass at the top of the slope begin to appear tension cracks. With the continuation of mining, the fissures gradually penetrate and develop along the steep inclined structural plane. With the development of cracks, the main dangerous rock mass at the top of the slope is collapse, while the lower dangerous rock mass moves downward along the slope in the way of sliding while breaking. The failure of the whole slope changes from collapse to landslide. Studying the mechanism of landslide and collapse in Pusha village, Zhangjiawan town, Nayong county, Guizhou province is of great significance to the study of potential hazards of similar conditions in mountainous areas of China and the future work of disaster reduction and prevention.