Protection measures on the failed cut-slope along the free expressway, Chembur, Mumbai, India

The present work summarizes the investigations made during the stability analysis of a cut slope across the basaltic rock mass of the Deccan traps. Kinematic analysis was done to understand the relation between the structural discontinuities and surface topography and to determine the probable modes of failure. The concerned slope was in very poor condition because of the discontinuity ornamentation and other construction activities in the vicinity. Due to steep cut slope and blocky nature of rock mass, rockfall investigation was done to identify the rockfall trajectory, bounce height and kinetic energy in order to design proper support systems against falling mass. Material model was later simulated using the Hoek and Brown parameters in a finite element method considering different structural discontinuities. The safety factor at this state was less than one, the result of which was the recurrent slope failure and hassled traffic movement along the expressway. Finally, with the help of field observations, investigations from rockfall analysis and numerical simulation, necessary remedial measures were suggested and implemented that showed tremendous results in terms of safety and stability.