湖北省宜昌市猇亭区人类工程活动与城市地质灾害

目的]探讨人类工程活动与城市地质灾害之间的因果关系,为城市规划以及城市建设提供理论依据。方法]采用现场地质环境调查方法(地质勘查、地质测绘),对湖北省宜昌市猇亭区人类工程活动形成的地质灾害进行调查研究,探讨城市建设过程中地质灾害形成的主要内、外在因素。结果]人工填土是猇亭区滑坡地质灾害形成的主要原因,且后期都具有转变成坡面泥石流的可能性;人工开挖是猇亭区潜在滑坡型不稳定斜坡地质灾害形成的主要原因;猇亭区区内与膨胀性黏土岩有关的地质灾害同样与人类工程活动密切相关,按照出露地表浅埋藏以及深埋藏形成不同的变形破坏类型;路面开挖以及路堑开挖造成膨胀性黏土岩大面积临空,在水的作用下形成塑性变形膨胀,引起路面和陡倾坡面变形破坏。结论]人类工程活动是城市地质灾害形成发展主要外在因素,同时宜昌市猇亭区所具有的水平(平缓)—层状—松散的岩土体结构类型是造成城市地质灾害的主要内部原因,膨胀性黏土岩的分布进一步加剧了地质灾害形成。

Engineering Activities and Urban Geological Disasters at Xiaoting District in Yichang City, Hubei Province

Objective] The aim of the study is to investigate the relationships between engineering activities and urban geological disasters, and provide help for the urban planning and construction. Methods] Based on the on-site geological environment survey(geological exploration, geological surveying and mapping), we studied the geological disasters caused by engineering activities at Xiaoting District in Yichang City, Hubei Province and probed into the internal and external factors causing these disasters. Results] Artificial excavation was the main cause of potential landslides on unstable slopes. Artificial refilling is the main cause of landslides with a potential to develop into debris flow. Geological disaster related to the expansive clay soil are also closely related to engineering activities. The excavation in road construction leads expansive clay soil to be unstable and to swell under the impact of rainfall, thus causing the road and steep slope deformation and failure.Conclusion] The engineering activities are the main external factors causing the geological disasters. The flat, laminated and loose structure of the rock and soil mass, and the distribution of expansive clay soil are the internal factors of geological disasters.