Reliability analysis of jointed rock slope considering uncertainty in peak and residual strength parameters

Tiwari, Gaurav and Latha, Gali Madhavi (2019) Reliability analysis of jointed rock slope considering uncertainty in peak and residual strength parameters. In: BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT, 78 (2). pp. 913-930.

PDF Bul_Eng_Geo_Env_78_2_913-930_2019.pdf - Published Version Restricted to Registered users only Download (6MB) | Request a copy

Abstract

Stability analysis of rock slopes is a complex problem because of uncertainties involved in the rock mass properties. The probabilistic approach is a rational way to deal with these uncertainties. This article investigates the stability of a rock slope by deterministic and probabilistic approaches by considering uncertainty in peak and residual strength parameters and strength-drop in stress-strain behavior of the rock mass. A Geological Strength Index (GSI) based on a quantitative approach was used to estimate the statistical parameters of peak and residual strength parameters. Reliability index of the slope was then estimated using Hong's Point Estimate Method coupled with the finite element method. The approach is demonstrated using an important case study of a Himalayan rock slope supporting the piers of the world's highest railway bridge. It was observed that the factor of safety and reliability index for the slope was highly sensitive to residual strength parameters, and; hence, ignoring strength-drop from the rock mass behavior and uncertainty in residual strength parameters can overestimate the factor of safety and the reliability index of rock slopes. A parametric study is carried out to evaluate the influence of the coefficient of variation of uniaxial compressive strength of intact rock, the Hoek-Brown strength parameter of intact rock, roughness and alteration parameters of the joints on the probability of failure and the reliability index. The approach is verified by comparing the estimated displacements along the slope with in-situ measured displacements observed during field monitoring over the years. The approach used can be extended to the rock slopes or rock slides where high displacements in the slopes are expected due to triggering forces like seismic forces, excavation or structural loads.

Item Type:	Journal Article
Publication:	BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
Publisher:	SPRINGER HEIDELBERG
Additional Information:	copyright for this article belongs to BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
Keywords:	Rock slope; Probabilistic approach; Residual strength; Geological strength index; Slope monitoring
Department/Centre:	Division of Mechanical Sciences > Civil Engineering
Date Deposited:	20 May 2019 09:41
Last Modified:	20 May 2019 09:41
URI:	http://eprints.iisc.ac.in/id/eprint/62426

Actions (login required)

View Item