Bheri Babai Diversion Multipurpose Project- Viability Study of Tunnel Boring Machine For Tunneling

Project Description

This study intends to critically examine the technical and economic feasibility of using a Tunnel Boring Machine (TBM) for the tunnelling of BBDMP excavation work in view of the fragile topographical and geological conditions of the tunnel alignment. Project involves reviewing of the topography, geology and hydrological/hydro geological features of the alignment along which tunnel is laid to understand the viability and preference of tunnel excavation by TBM vis-à-vis Drill and Blast Methodology (DBM). Evaluation of the feasibility of tunnel excavation by TBM from the point of view of logistics and infrastructures, existing/proposed road network for transportation, availability of working space at site for TBM assembly and erection and the availability of ancillary support services required for its functioning and final dismantling is done. Prediction of TBM’s performance (Rock type wise) based on available data on geology and hydrology/hydrogeology of the tunnel alignment and an evaluation of muck disposal due to tunnel excavation by TBM vis-a-vis DBM was done. Recommendations on the use of TBM for BBDMP Tunnelling work including suggestion for essential investigations and tests were given.

Assignment Description

The services provided in Viability Study of Tunnel Boring Machine for Tunnelling were review of the detailed design report and soil investigation reports of the BBDMP prepared by the project, encompassing the topography, geology, hydrological/hydro geological features of the alignment along the tunnel alignment, visiting of the project area to better understand the topography, geology and other important features related to the project, comparing the different options for the tunnel excavation mainly using TBM or conventional method (Drill and Blast Method), evaluating the viability of the tunnel excavation by TBM from the point of view of logistics and infrastructures. Assessing the existing/proposed road network for transportation considering the width of road and curvature and capacity of bridges to transport the TBM to the site. Similarly, possibility of widening the road at bends was studied in details. Study for the availability of the working space at site for TBM assembly and erection and the availability of ancillary support services required for its functioning and final dismantling was also carried out.