KARJAT-LONAVALA SECTION OF THE CENTRAL RAILWAYS - MAHARASHTRA - India
ROCKFALL MITIGATION – MONKEY HILL- THAKURWADI STRETCH-116/300 -500
Figure-2 Staking out in progress to identify post locations
Figure-3 Site preparatory works in progress (railway line below the slope)
Figure-4 Installation of rockfall barrier in progress
Figure-5 Installation of rockfall barrier in progress
Figure-6 View of 40m long rockfall barrier installed
The stretch length between Thakurwadi – Monkeyhills is located on the Karjat-Lonavala section of the Central Railways on a mountain passage (Bhor Ghat) situated at the crest of the Western Ghats in Maharashtra, India. Many tourist places such as Monkey Hill and Gorakshnath Temple / Nathbaba are present along the stretch length which attracts many tourists here. A deep crevice (a natural water flow channel) is present with large number of boulders wedged in the gap between chainages KM 116/300 and 116/500. Here rockfall events are reported of size approx. 0.6m(max). The exposed terrains is subjected to heavy rainfall during monsoons and due to the rainfall infiltration, there is an increase in pore pressure within the rock discontinuities. This when accompanied by the erosion factors and the steepness of the slope, the rocks quickly lose their tensile and shear strength hence triggering the rock detachment. These events usually affect the movement of trains along this route.
As per the site observations, previous history of rockfall incidents in this area and analysis, a critical location along chainage km 116/300 – 116/500 is identified for rockfall mitigation. Rockfall barrier of nominal capacity 5000kJ and 7m height has been proposed for 40m stretch length on the hill slope above the existing railway line to prevent the falling of loose boulders on track and thereby mitigating the risk of rock detachments from upslope locations from affecting the infrastructure below.