A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Back Analysis of Landslide Deposit Basal Failure Plane Residual Shear Strength
Landslide deposits are geologic features that show signs of movement ("failure") which occurred outside the historical record. Unlike recent landslides, they do not show evidence of recent movement such as a defined head scarp, tension cracking, and/or bulging at the toe, but are identified by geomorphic evidence of past movement. Back analysis of landslides is a common technique used to assess shear strengths for design wherein a factor of safety (FS) equal to 1.0 is assumed along a pre-defined failure surface. However, as landslide deposits may no longer be "at the verge" of failure, a back analysis with an assumed FS equal to 1.0 may result in excessively conservative shear strength properties. Therefore, back analysis of landslide deposits should be performed assuming a FS greater than 1.0. As there is no consensus on how much higher than unity FS should be, values typically used in practice range between FS = 1.05 and 1.25 with little, if any, justification provided for FS selected. Consensus on seismic FS and/or calculated maximum permanent seismic displacement for use in back analysis is similarly lacking. In this paper we evaluate parameters that affect back analysis of landslide deposits and provide illustration using a recent case history from our practice.
Back Analysis of Landslide Deposit Basal Failure Plane Residual Shear Strength
Landslide deposits are geologic features that show signs of movement ("failure") which occurred outside the historical record. Unlike recent landslides, they do not show evidence of recent movement such as a defined head scarp, tension cracking, and/or bulging at the toe, but are identified by geomorphic evidence of past movement. Back analysis of landslides is a common technique used to assess shear strengths for design wherein a factor of safety (FS) equal to 1.0 is assumed along a pre-defined failure surface. However, as landslide deposits may no longer be "at the verge" of failure, a back analysis with an assumed FS equal to 1.0 may result in excessively conservative shear strength properties. Therefore, back analysis of landslide deposits should be performed assuming a FS greater than 1.0. As there is no consensus on how much higher than unity FS should be, values typically used in practice range between FS = 1.05 and 1.25 with little, if any, justification provided for FS selected. Consensus on seismic FS and/or calculated maximum permanent seismic displacement for use in back analysis is similarly lacking. In this paper we evaluate parameters that affect back analysis of landslide deposits and provide illustration using a recent case history from our practice.
Back Analysis of Landslide Deposit Basal Failure Plane Residual Shear Strength
Matasovic, N. (author) / Conkle, C. (author) / Witthoeft, A. F. (author) / Stern, A. (author) / Hadj-Hamou, T. (author)
Second International Conference on Geotechnical and Earthquake Engineering ; 2013 ; Chengdu, China
IACGE 2013 ; 471-480
2013-10-09
Conference paper
Electronic Resource
English
Back Analysis of Landslide Deposit Basal Failure Plane Residual Shear Strength
| British Library Conference Proceedings | 2013
Shear Strength Characterization and Back Analysis for a Landslide Complex
| British Library Conference Proceedings | 2012
Strength Recovery of Landslide Soils from the Residual State of Shear
| British Library Conference Proceedings | 2014
Application of Back Analysis Method in Selecting Shear Strength Parameters for Hutoumao Landslide
| British Library Conference Proceedings | 2015