三峡库区神农溪段消落带岩体劣化对地质灾害的影响

The Effect of Rock Mass Deterioration on Geological Disasters in the SubsidenceZone of Shennongxi Section in the Three Gorges Reservoir Area

三峡库区内地质灾害现象较多,是一重要的环境地质问题。消落带的劣化程度逐步增大,据统计分析,其对地质灾害的影响也愈发严重。因此在三峡库区神农溪范围通过野外调研查明消落带岩性为碳酸盐岩和碎屑岩两大类,消落带岩体劣化表现形式为节理裂隙的强烈发育、凹岩腔、表层剥落三种。并通过分析干湿循环实验结果,预测劣化趋势及机理,分析统计调研区内地质灾害的发育情况,推测消落带岩体劣化对地质灾害发育的影响愈发变大这一结论。研究因消落带岩体劣化诱发地质灾害的成灾模式为滑坡和崩塌两种,分析其成灾机理,为进一步了解三峡库区同类地质灾害提供理论依据,支撑后期库区防灾减灾工作。

There are many geological disasters in the Three Gorges Reservoir area,which is an important environmental geological problem.According to the statistical analysis,the influence of the subsidence zone on the geological disaster is more and more serious.Therefore,through field investigation inShennongxi area of the Three Gorges Reservoir area,it is found that the lithology of the depression zone is carbonate rock and clastic rock.The deterioration of the rock mass in the depression zone is manifested in three forms:strong development of joint fissures,concave rock cavity and surface peeling off.Through the analysis of the results of the dry wet cycle test,the deterioration trend and mechanism are predicted,the development of geological disasters in the investigation area is analyzed,and the conclusion that the deterioration of the rock mass in the depression zone has more and more influence on the development of geological disasters is inferred.In this paper,two types of geological disasters induced by rock mass deterioration in the subsidence zone are studied,i.e.landslide and collapse.The disaster mechanism is analyzed to provide theoretical basis for further understanding of similar geological disasters in the Three Gorges Reservoir area and to support the disaster prevention and mitigation work in the later period.