Wedge Failure Analysis of Slopes in Highly Jointed Rock Masses in the Zones of High Seismicity

Mantrala, S and Kumar, H and Verma, AK and Sitharam, TG (2022) Wedge Failure Analysis of Slopes in Highly Jointed Rock Masses in the Zones of High Seismicity. In: Indian Geotechnical Journal .

PDF ind_geo_jou_2022.pdf - Published Version Restricted to Registered users only Download (3MB) | Request a copy

Abstract

Wedge failure is the predominant failure mode in slopes with highly jointed rock mass. The orientation of the joints of the rock mass governs the stability of the slopes depending upon their orientation relative to the orientation of the slope. Extensive slope stability analyses were carried out for the slopes of Chenab bridge. These analyses pointed out that the stabilization measures need to be designed against the wedge failures. This paper presents the various special considerations of the wedge failure analyses like application of the seismic accelerations, load cases considered for analysis and factors of safety required. A summary of the various analyses and important conclusions drawn there from are presented. Some of the observations like the load case with higher factor of safety demanding higher anchor force and foundation loads improving the factor of safety are counter intuitive. Since sliding of the wedge either along a joint plane or along the line of intersection of two joint planes is like a block sliding on a plane, using the sliding block analogy, the reasons for the specific observations noted during the detailed wedge failure analyses of Chenab bridge slopes are explained. The study lays emphasis on the anchor force or stabilizing force required in the analysis and design over factor of safety since the design is always governed by the former. The study recommends special considerations for the wedge failure analysis in highly seismic areas like the direction of seismic accelerations, designing for MCE condition, analysis during construction stage, etc. © 2022, The Author(s), under exclusive licence to Indian Geotechnical Society.

Item Type:	Journal Article
Publication:	Indian Geotechnical Journal
Publisher:	Springer
Additional Information:	The copyright for this article belongs to Springer
Keywords:	Bridges; Factor analysis; Failure (mechanical); Rock mechanics; Rocks; Safety factor; Seismic design; Seismology; Slope stability, Factors of safeties; Horizontal seismic acceleration; Jointed rock mass; Line of intersection; Seismic accelerations; Sliding block analogy; Sliding blocks; Vertical seismic; Vertical seismic acceleration; Wedge failures, Failure analysis
Department/Centre:	Division of Mechanical Sciences > Civil Engineering
Date Deposited:	16 Mar 2022 06:12
Last Modified:	16 Mar 2022 06:12
URI:	http://eprints.iisc.ac.in/id/eprint/71505

Actions (login required)

View Item