厚软岩山坡与排土场协同灾变诱发泥石流的研究

【作者】 姜亭亭；

【导师】 孙世国； 王运霞；

【作者基本信息】 北方工业大学 ， 结构工程， 2009， 硕士

【摘要】 排土场安全问题不仅直接关系到矿山的安全生产,还涉及到周边环境的安全及附近居民的安危。然而对于那些场址工程地质条件不好的排土场而言,由于厚软岩基底的承载力低,如何合理安排排土顺序、确定排土参数等因素直接影响到矿山生产的安全、也影响到排土场的正常使用和周边环境的安全。为此本论文针对厚软基底排土场边坡的安全评价、排土场与厚软基底山体的协同破坏机制及其可能诱发滑坡和泥石流等问题进行了研究,并对相关的安全防护措施以及后续排土场的优化设计等问题进行了分析,主要完成的研究内容如下:1)从理论和数值分析两个方面系统地分析了松散废石土体形成泥石流的条件、转化机理和滑坡的流态化过程;而在土体液化过程中水的参与起了关键作用,因此,在数值模拟过程中,提出了用含水量作为变量来模拟降水过程中土体逐渐失稳的过程,揭示了厚软岩达到泥石流启动临界降雨点之前的力学状态。2)借鉴山体泥石流危险度评价方法,结合排土场特点,提出了小区域厚软基底山坡体与排土场协同破坏诱发泥石流危险度判别方法,并进行了危险性区划分析,据此给出宜昌石灰石矿排土场危险区域的判别结果;3)对宜昌石灰石矿排土场滑坡与泥石流防治体系进行了如下内容的研究与设计:(1)应用极限平衡理论对排土场进行了稳定性分析与评价,给出合理的减载和排土方案;以便减少废石土体集中堆积高度,避免产生集中荷载;(2)在排土场上部开挖截洪沟,在滑动变形体上开挖疏导水路,以便减少汇水区的面积和雨水汇集量,减小雨水对滑体的入渗量;(3)在下部水沟里设计了排水暗渠,防止局部陡峭山体滑坡堵塞自然水沟并形成堰塞湖;(4)综合应用被动土压力和力学原理的集成技术,提出并设计了坝体抗倾覆“称”状基础形式,工程实际应用效果良好;通过上述研究,建立了一套完整的厚软基底山坡条件下的排土方案与边坡安全及泥石流灾害的防治体系,经过一年运行与实际监测数据分析,边坡同期变形对比减小了66%,收到了良好的效果。同时该研究成果还推广应用到云南红田煤矿排土场,同样收到良好的经济与社会效益。更多还原

【Abstract】 The safety of the dump involves not only the safe production,but also the safety of surrounding environment and the local residents.Because the bearing capacity of thick soft rock is low,for the waste dump without good engineering geological condition,it is important how to arrange reasonably the order of dumping waste and to determine the dump parameters,which directly affect the safety and normal usage of the mine production,and the safety of surrounding environment.According to the safety evaluation of the thick soft rock foundation,the collaborative failure of the dump and thick soft rock foundation and the optimum design of subsequent dump, this paper doing some related research,mainly content completed are as follows:1)Systematical analysis the conditions in which the loose earth-rock forms debris flow,and transformation mechanism in theory and numerical simulation,as well as the fluidization of landslide;during the soil liquefying,water is a key role,therefore, during the numerical simulation,propose that use the water content as variable to simulate the gradually instability process of the soil,reveal the mechanics condition of thick soft rock before reaching critical rainfall point of the debris flow initiation.2)Using hill debris risk assessment method for reference,combined with the characteristics of the dump,propose the debris risk assessment method by which evaluate debris risk when the thick soft rock coorperate with the dump,and divide its risk,hereby this paper gives the discriminant result of the dump dangerous area.3)According to YiChang limestone dump landslide and debris prevention system, doing the reseach in this paper is as follows:(1)Using limit equilibrium theory,analysis and evaluate the risk of the dump,and give reasonable load reduction and soil heap scheme;reducing the accumulation height of the soil not to produce concentrated load;(2)At the upper part of the dump digging a flood-cutting channel and on the deformable body digging guide-water way to reduce the collection area and the water-collecting amount,reducing the infiltration capacity of the rain;(3)In the lower water ditch setting a drainage covered conduit prevent the landslide of part steep hill to block nature channel and form barrier lake;(4)With comprehensive application of the integration technology of passive earth pressure and soil mechanics,propose and design "scale" shape foundation,with good effect in engineering;By above reseaches,construct a complete set of dumping form and debris disaster prevention system,and by the operation and practical monitor date,synchronization deformation of the slope has decreased 66%as a good effect.At the same time,this reseach result was also promoted and applied to the dump of HongTian coal mine in YunNan,receiving a good economic and social benefits.更多还原