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Bull Eng Geol Environ (2014) 73:9971011 DOI 10.1007/s10064-014-0645-1
ORIGINAL PAPER
A coupled slope cuttinga prolonged rainfall-induced loess landslide: a 17 October 2011 case study
Jian-qi Zhuang Jian-bing Peng
Received: 28 December 2012 / Accepted: 30 June 2014 / Published online: 26 July 2014 Springer-Verlag Berlin Heidelberg 2014
Abstract Continuous and heavy precipitation in the early September 2011 triggered several landslides in Xi an, Shaanxi province, China. A particularly relevant example is the Bailu tableland landslide occurrence on 17 September 17 2011, which was responsible for 32 casualties. This was selected as a case study for investigating the trigger factors, formation process, and hazard characteristics of the landslides of this type. The results showed that: (1) The Bailu landslide possessed a relative height = 90 m and width = 170 m, respectively, an average initiation thickness was 10 m, a sliding direction and distance of 55 and 150 m, respectively, a total volume of 15 9 104 m3, and an
average deposit thickness of 12 m; (2)The main trigger factors were excessive slope cutting with a heavy and long duration of rainfall; (3) The landslide was a typical example of its type, based on the trigger factors since the formation process of the landslide is generally as follows: cutting leads to gravitational and stress eld redistribution, initiating the appearance of cracks, which then enlarge after the continuous inltration of rainwater. This results in the formation of additional cracks, and nally, slope failure; and (4) Based on our analyses of this landslide and previous events, we proposed equations to determine the critical precipitation threshold and the potential risk distance. This study provided an important reference for understanding and studying the mechanisms of this type of
landslide, as well as guidelines for future disaster prevention and mitigation in this region.
Keywords 9.17 landslide Trigger factors Formation
mechanism Loess landslide Cutting slopes
Introduction
More than 1,000 geological hazards occurred in China annually between 2003 and 2013, resulting in an annual death toll of over 420, in addition to signicant property damage and environmental destruction (Chinese Geological Environment Bulletin 20032010). Landslides and collapses accounted for over 80 % of those geohazards, and of these, one third occurred in Loess Plateau. Loess Plateau lies in the middle reaches of the Yellow...