Failure Mechanismof Preferred Structure Plane Controlled Lithologic Slope During Intensive Earthquake

详细信息   

• 责任者：Lu Gongda (Faculty of Engineering ; China University of Geoscience ; Wuhan 430074 ; China) ; Yan Echuan
• 刊名：Journal of Engineering Geology
• 出版年：2012
• 卷期：20(3)
• 关键词：岩质边坡 ; rock slope ; 地震效应 ; seismic effects ; 四川 ; Sichuan Province
• 页码：p.305-310
• 图表：2 illus., 10 refs.
• 分类号：1702
• issnNo：ISSN1004-9665
• isbnNo：CN11-3249/P

摘要

This paper considered two typical geo-hazards triggered by the 5.12 Wenchuan earthquake, and analyzed their stereographic projection, it worked out the combination modes of preferred structure planes which controlled the slope stability. Then, it applied numerical simulation with discrete elements software to simulate their process of failure. The results show the following two failure modes. The first mode of slope failure during earthquake is that, the layered slopes that dip gently outwards crack its top at first, meanwhile the structure planes inside the slope start to undergo shear deformation. As the cracks on the top extend downwards and when these cracks reach the structure planes dip outwards inside the slope, the entire slope will slide along those connected planes. Their deformation and failure mechanism is slide-rip. Their mode of failure is bedding-layer cutting slide. The second mode of slope failure during earthquake is as follows. The steep block slopes crack their tops and loose themselves at first. Then, the blocks cut and formed by structure planes start to undergo shear deformation along the structure planes which dip gently inwards or horizontal at the bottom of those tensile cracks. Then, these blocks gradually slip outwards due to the durative earthquake, roll and fall down the slopes. Their deformation and failure mechanism is rip-slip. Their mode of failure is slipping collapse.