| 摘要: |
| 大西安正在进行国际化大都市的建设，建设过程中的政府决策、防灾减灾、规划设计、施工与运营管理等环节都面临着许多与岩土体和地质环境相关的重大问题，尤其是滑坡治理与预报工作。本文通过大量野外调查、测绘和勘查，统计分析了大西安地区发育的滑坡，将大西安地区的滑坡按滑体特征、动力成因和滑动特征分为三大类，又进一步按诱发因素、物质组成、滑面埋深、滑体规模和力学性质进行相应的分类，并从滑坡形貌、滑带与纵断面、变形与运动特征等方面对大西安地区发育的滑坡进行了归纳总结，建立了大西安地区具有层次性的滑坡分类体系。为大西安地区滑坡监测预报和稳定性分析等奠定了基础，为该区的防灾减灾工作提供理论依据。 |
| 关键词: 西安 滑坡 分类 特征 黄土 |
| DOI：10.7515/JEE182006 |
| CSTR：32259.14.JEE182006 |
| 分类号: |
| 基金项目:陕西省国际科技合作与交流计划项目（2016KW-030）；国土资源部黄土地质灾害重点实验室开放基金（KLGLAMLR201502）；国家自然科学基金项目（41772323）；国家重点研发计划项目（2017YFD0800501） |
| 英文基金项目:International Scientific and Technological Cooperation and Exchange Program in Shaanxi Province, China (2016KW-030);Open Fund of the Key Laboratory for Geo-hazards in Loess Area of the Ministry of Land and Resources (KLGLAMLR201502); National Natural Science Foundation of China (41772323); National Key Research and Development Program of China (2017YFD0800501) |
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| An analysis of landslide classifications and characteristics in Xi’an |
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XIE Wanli, TENG Hongquan, DU Lei, CHENG Tian’e, YANG Hui, YU Hong
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1. State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an 710069, China
2. Key Laboratory of Mine Geological Hazards Mechanism and Control, Xi’an 710054, China
3. Shaanxi Institute of Geological Survey, Xi’an 710054, China
4. College of Urban and Environmental Sciences/School of Foreign Languages, Northwest University, Xi’an 710069, China
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| Abstract: |
| Background, aim, and scope The study site is located in the inland region of mid-latitudes characterizing a temperate and monsoon climate. Due to the change of meteorological factors, there is often disastrous weather, such as rainstorms, continuous rain and so on, which not only causes floods, but leads to natural landslides. Meanwhile, the new tectonic movement is active in the region and the terrain is complex and changeable. As a result, the landslides in the region develop fully with large density and strong intensity. Materials and methods Through a lot of field investigations and statistical analysis, the authors established the landslide classification system. Results The landslides in greater Xi’an region are mainly loess landslides, induced by rainfall and human engineering activities, which is mainly due to the special loess sediments with high heterogeneity, porosity, erect and collapsibility, the vertical joints fully formed in the loessificaion process and nearly vertical structural joints formed under tectonic stress in the late stage. Besides, with erosional surface falling and the slope height increasing under the rain and gravity, the slope stress increases constantly and is relatively more concentrated. Thus, the micro cracks form the shear zone and these failure surfaces facilitate the erosion of rain, surface water and groundwater. On the one hand, the action of water facilitates the development of the sliding surface. On the other hand, the softening and argillitization of the sliding surface soil greatly reduce the friction between the upper and lower part of the failure surface, leading to the occurrence of landslides. Discussion The initial formation, development, generation and even extinction of the landslides are always affected by both the internal and external factors. Among them, the sliding body composition, geological conditions and mechanical properties are intrinsic factors and the dynamic origins (predisposing factors) are external ones, including material composition, mechanical properties and dynamic reasons, which is an important basis for landslide classification. In the process of constructing an international metropolis of Xi’an, the government decisions, disaster prevention and mitigation, planning and design, construction and operation management are faced with many major issues related to rock-soil mass and geological environment, especially landslides’ treatment and forecast. Based on field investigations, the present study analyzed the landslides in greater Xi’an and established a hierarchical landslide classification system which classified the landslides in greater Xi’an into three types, namely landslide characteristics, formation causes and sliding features. It further classified the landslides based on the inducing factors, material composition, embedded depth of sliding surface, sliding scale and mechanical properties. Additionally, the characteristics of landslides in greater Xi’an were summarized from the aspects of landslide morphology, sliding zone and longitudinal section as well as deformation and movement characteristics. The above analysis lays a foundation for establishing a geological model system of landslides monitoring, predicting and analyzing stability, which provides a theoretical basis for preventing and mitigating disasters in the region. Conclusions The occurrence of landslide is related to the type and characteristics of landslides and the landslides in greater Xi’an region are also related to loess, rainfall and human activities. Therefore, it is necessary to study the characteristics and types of landslide hazards in the area, which can provide theoretical basis for disaster prevention and mitigation in order to achieve the goal of the harmonious development between urban development and environment. Recommendations and perspectives We must also try our best to monitor and prevent landslides, especially in rainy seasons. Besides, we need to further landslide study in the area to provide a theoretical basis for the establishment of landslide monitoring, prediction, stability analysis, the disaster prevention and mitigation work. |
| Key words: Xi’an landslide classification characteristics loess |
