RAIN-INDUCED SLOPE INSTABILITY IN HONG-KONG

Authors
Citation
Swc. Au, RAIN-INDUCED SLOPE INSTABILITY IN HONG-KONG, Engineering geology, 51(1), 1998, pp. 1-36
Citations number
81
Categorie Soggetti
Engineering, Geological","Geosciences, Interdisciplinary
Journal title
ISSN journal
00137952
Volume
51
Issue
1
Year of publication
1998
Pages
1 - 36
Database
ISI
SICI code
0013-7952(1998)51:1<1:RSIIH>2.0.ZU;2-D
Abstract
Slope failures are common in Hong Kong. A wide spectrum of slope failu res have been noted. Failures may differ in respect of thickness of fa iled mass, time of failure occurrence, rotational inclination, failure movement rate, mobility of debris, etc. Small failures significantly outnumber large ones. Due to their close proximity to buildings, howev er, small failures that collapse catastrophically without prior warnin g are of concern. Intense rainfall, soils that are largely non-cohesiv e upon saturation, steep terrain, and intense development are consider ed to be the major causes of the failures. Loss of pore-water suction, erosion, and pore-water pressure build-up at shallow depths are the m ost common ways through which rainwater affects the slope stability, a s short-burst rainstorms are common. The scale of a failure event depe nds on the intensity, areal extent, position and duration of the trigg ering rainstorm. Antecedent rainfall has relatively little influence. The prediction of slope stability in Hong Kong is difficult because of the highly erratic nature of the hydrological influences and the inhe rent heterogeneity of local soils. While some of the hydrological and geological attributes cannot be accurately predicted and effectively c ontrolled, the hazard can be mitigated by appropriate geotechnical con trol. (C) 1998 Elsevier Science B.V. All rights reserved.