重庆市南川甑子岩危岩形成演化机制分析及防治措施探讨

Analysis on formation and development mechanism and discussion on prevention measures for Zenziyan dangerous rock mass in Chongqing

地质灾害的形成严重制约地方经济的发展,灾害形成机制研究可为其治理提供科学依据。重庆市地质灾害主要表现为滑坡、崩塌。对于前者已有较多的研究,而后者开展的工作甚少。甑子岩危岩体全长近1400m,潜在崩塌体积约444 06万m3。目前危岩带岩体处于时效变形破坏阶段,变形仍在继续,特别是在暴雨及其它人为因素的作用下,很可能突发崩塌灾害,危及附近居民及铝矿厂的安全。为此已引起了有关方面的高度重视。文章从地形地貌、地层岩性、坡体结构、降雨、风化、温度、植物、人类工程活动等方面对危岩的形成机制进行分析,得出上硬、下软的岩体地质结构是危岩形成的物质条件,采矿活动是危岩形成的最重要的原因的结论。通过危岩变形破坏演化过程的剖析,确定了危岩变形的两种破坏模式:倾倒式破坏、基座剪切滑塌式破坏。在此基础上结合Ⅰ、Ⅱ区危岩的不同危害性,建议采取分区治理。通过施工条件、经济合理性、治理效果、社会效应4方面的优劣对比,对Ⅱ区危岩南坡村民居住区搬迁避让比治理Ⅱ区危岩体更经济、有效。由于铝矿厂搬迁难度极大,因此对Ⅰ区危岩体采取排水、封闭裂缝、填实采空区、填补凹腔、锚固、拦挡的综合治理措施。

The geological hazards greatly restrain the development of provincial economy.The analysis on formation mechanism of the hazards can provide a reliable scientific basis for harnessing the hazards.Chongqing's geological hazards mainly are landslide and rockfall.The research level on landslide is high,but low on rock fall.Zenziyan dangerous rock mass is about 1400?m long,and about 444.06×10~4m ~3 scal.At present,the dangerous rock mass is at the stage of secular distoration and is deforming continully.Under the action of rainstorm and human being,it is possible for the rock mass to fall down and threaten the neighboring residents and aluminum ore factory.So the dangerous rock mass has received much attention. By analyzing its formation mechanism from topography,physiognomy,stratum lithology,slope structure,rainfall,weathering,temperature,plant and human engineering movementu etc,it can be concluded that the special rock struction with hard rock in the above and soft in the below is the physical condition of forming dangerous rock mass,and mining is the foremost reason.By analyzing the deformation development trend of the dangerous rock mass,this paper presents the two dangerous rock mass deformation and failure style,i.e.dumpage and slump.Considering the different risks in Ⅰ and Ⅱ section,it is suggested to take different remedy measures.By comparing the four aspects: construction condition,economic rationality,remedy effect and social domino effect, it comes to the conclusion that removing the house on the south of Ⅱ section to avoid the dangerous rock mass is more economical and effective than harnessing it.Because it is very difficult to remove aluminum ore factory on the I section,so we should take measures including drainage,sealing flaw,goaf filling,reentrant filling,anchorage and intercept,to remedy Ⅰ section.This paper can be used for reference to study similar geo-hazards.