摘要
2002年9月18日13:40,在连降暴雨的影响下,深圳一填土边坡发生滑坡,约2.5×104m3的松散填土体在水平地面高速滑动了140m,造成5人死亡3、1人受伤。文章首先介绍了滑坡区的地质环境特点及滑坡特征;为了揭示该滑坡的发生机理,开展了松散击实填土的等压固结不排水剪(ICU)及常剪应力排水剪(CS)试验。ICU试验结果表明,土体具有明显的应变软化特性并伴随孔隙水压力的上升;CS试验结果表明,土体在低围压条件下破坏具有突然性,破坏过程中孔隙水压力急剧上升,表明土体出现突然性结构丧失。ICU及CS试验均表明松散填土具有静态液化特性。从现场孔隙比与稳态线(SSL)的关系来看,原位填土的状态参数位于稳态线上方,因此该填土边坡是由于地下水位上升造成土体出现静态液化、液化土体形成流滑所致。无限斜坡稳定分析表明造成该填土边坡破坏需要有较高的地下水位。
At 13：40 on September 18, 2002, a fill slope failed following a period of prolonged rain in Shenzhen, resulting in 5 fatalities and 31 injuries. This post-failure investigation was mainly directed at evaluating the possible mechanism of the failure. During the investigation, data were collected on the topography and subsurface stratigraphy. Field tests were carried out to obtain in-situ density and permeability coefficient of the fills. Strain-softening and collapse behaviours were observed in isotropically consolidated undrained （ICU） and constant shear stress （CS） tests, respectively, on loosely compacted soil. Void ratios obtained from the in-situ density tests are compared with the steady state line, and it is shown that the fills are above the steady state line, it was thus concluded that the failure was triggered by static liquefaction, resulting in a consequent flowslide. The slope stability analyses indicated that a high groundwater level was required to initiate the failure.
出处
《中国地质灾害与防治学报》
CSCD
2007年第2期1-8,共8页
The Chinese Journal of Geological Hazard and Control
关键词
填土边坡
降雨
等压固结不排水剪(ICU)
常剪应力排剪(CS)
流滑破坏
静态液化
深圳
fill slope
rainfall
isotropically consolidated undrained shear stress test
constent shear stress test
flowslide failure
static liquefaction
Shenzhen
