Analysis and behavior of preexisting landslides
type: CreativeWork
description: The selection of shear strength parameters for the design and repair of landslide is important and difficult. Skempton (1964) concludes that if a failure has already occurred in clayey soils, any subsequent movement along the preexisting slip surface will be controlled by the drained residual strength. Skempton (1985) suggests that the strength of a clay also will be at or close to the residual value on slip surfaces in soliflucted slopes, bedding shears in folded strata, sheared joints or faults, and after an embankment failure. Therefore, the drained residual shear strength has been and still is being used for analysis of slopes that contain a preexisting shear surface. Some recent research suggests that preexisting shear surfaces may exhibit a shear strength that is greater than the drained residual value after a period of time in which the slope remains stable, i.e., does not experience shear displacement. If so, strength recovery could impact landslide mitigation and remedial measures because the increased strength could result in savings to insurance companies and/or landslide mitigating agencies. Thus, it is important to determine if the shear strength after a long rest period during which no movement occurred still corresponds to the residual strength or has attained a strength that is greater than the residual value. The main objectives of this research are to study the shear strength and long term behavior of landslides and in particular preexisting shear surfaces. The research involved laboratory testing to determine the strength recovery, if any, of cohesive soils with varying plasticity, effective normal stress, and the applicability of the recovered strength to remedial measures and the back-analysis of landslides. Some of the issues addressed include (a) if the shear strength increases from the residual value with time, (b) what is the maximum recovered strength, (c) how long does it take to reach the maximum recovered strength, (d) if the strength in…
abstract: The selection of shear strength parameters for the design and repair of landslide is important and difficult. Skempton (1964) concludes that if a failure has already occurred in clayey soils, any subsequent movement along the preexisting slip surface will be controlled by the drained residual strength. Skempton (1985) suggests that the strength of a clay also will be at or close to the residual value on slip surfaces in soliflucted slopes, bedding shears in folded strata, sheared joints or faults, and after an embankment failure. Therefore, the drained residual shear strength has been and still is being used for analysis of slopes that contain a preexisting shear surface. Some recent research suggests that preexisting shear surfaces may exhibit a shear strength that is greater than the drained residual value after a period of time in which the slope remains stable, i.e., does not experience shear displacement. If so, strength recovery could impact landslide mitigation and remedial measures because the increased strength could result in savings to insurance companies and/or landslide mitigating agencies. Thus, it is important to determine if the shear strength after a long rest period during which no movement occurred still corresponds to the residual strength or has attained a strength that is greater than the residual value. The main objectives of this research are to study the shear strength and long term behavior of landslides and in particular preexisting shear surfaces. The research involved laboratory testing to determine the strength recovery, if any, of cohesive soils with varying plasticity, effective normal stress, and the applicability of the recovered strength to remedial measures and the back-analysis of landslides. Some of the issues addressed include (a) if the shear strength increases from the residual value with time, (b) what is the maximum recovered strength, (c) how long does it take to reach the maximum recovered strength, (d) if the strength in…
author: Hussain, Manzoor
language: en
keywords: Soil mechanics, Landslides, Overconsolidated clays, Shear strength, Strength recovery, Slope stability, Ring shear test
date published: 2010-05-19T18:33:55Z
date modified: 2026-07-22T22:25:08Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/16071