M. Ahmad, R. K. Umrao, M. K. Ansari, Rajesh Singh, T. N. Singh
Department of Earth Sciences, Indian Institute of Technology Bombay Powai, Mumbai, India.
DOI: 10.4236/gm.2013.31002   PDF    HTML     6,362 Downloads   11,975 Views   Citations

Abstract

Rockfall is a major problem in high hill slopes and rocky mountainous regions and construction of highways at these rockfall prone areas often require stable slopes. The causes of rockfall are presence of discontinuities, high angle cut slopes, heavy rainfall, and unplanned slope geometry etc. Slope geometry is one of the most triggering parameters for rockfall, when there are variations in slope angle along the profile of slope. The Present study involves rockfall hazard assessment of road cut slopes for 15 km distance starting from Mahabaleshwar town along State Highway-72 (SH-72). The vertical to subvertical cut slopes are prone to instability due to unfavorable orientation of discontinuities in slope face of weathered and altered basaltic rockmass. The predominant type of instability has been found as wedge type failure involving medium to large size blocks. In order to investigate the existing stability conditions, analyses were carried out at two locations under different slope conditions. The kinematic analysis was performed using stereographic projection method. RockFall 4.0 numerical simulator software was used to calculate the maximum bounce heights, total kinetic energies and translational velocities of the falling rockmass blocks, and a comparative analysis is presented with increasing the mass of blocks and height of the slope. The result of numerical analysis shows that varying slope angle geometry creates more problems as compared to the mass of blocks in the scenario of rockfall.

Keywords

Rockfall; Bounce Height; Kinetic Energy; Transverse Velocity; Mahabaleshwar; SH-72

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Conflicts of Interest

The authors declare no conflicts of interest.

References

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