Robbins TBM makes history in LaosA 7.6 m-diameter Robbins single shield TBM has completed the first mechanically-driven tunnel in Laos at Theun Hinboun hydro project. The 5.5 km-long drive for the headrace tunnel broke through before Christmas into a shaft close to the intake structure, with the TBM having averaged around 19 m/day advance in the hands of contractor CMC di Ravanna. Read the press release and visit tunnelbuilder archive la/11. 03/11.