Muck Cars Designed by CSM Bessac Receive Innovation AwardThe Roll and Rock process designed by CSM Bessac, a small-to-midsize TBM maker based near Toulouse, France has received a French construction federation award last month in Paris. Spoil removal by means of muck cars requires big gauge equipment. Traditional muck trains used in large diameter tunnels run on tracks, take much room and are only able of carrying small volumes of spoil with regard to their size. Such equipment is unsuited to small size tunnels as they cannot deal with all logistics tasks during tunnelling like the placement of the concrete segments, the spoil removal and grout injections.The new innovative Roll and Rock process consists mostly of wheels able to turn on themselves in two perpendicular directions together with a pendular suspension. The muck cars mounted on tyre wheels can therefore be driven directly on the tunnel lining. Better mucking-out rates are achieved, especially for small diameter tunnels. A wheel on rollers has been designed allowing to carry and drive the muck equipment both lengthwise parallel to the tunnel axis and transversally. A special chassis equipped with a specific suspension system has also been designed. The bearing chassis is modular and can be used in tunnels ranging from 1.8 m to 2.2 m in diameter. More from Jean-Marc Sabatié, e-mail jean-marc.sabatie@csmbessac.com and visit www.csmbessac.com 32/03.