2019/08/30 by Morton, J. D., Dunbar, D. D., Palmer, J. H. L.
#béton préfabriqué #clay soils #matériel minier #mining equipment #percement de tunnel #precast concrete #revêtement de tunnel #sol argileux #tunnel linings #tunnelling
paper · doi:10.4224/40001224
A tunnelling procedure using a full-face tunnel boring machine together with a precast segmented concrete tunnel lining has been developed in Canada and has been used successfully for a 2.16 m diameter tunnel in soft to firm clay at a depth of 10 to 12 m. The lining consists of rings composed of four trapezoidal sections of unreinforced concrete, 1 m in length and 11 cm thick. Each ring was assembled within the protection of the tailpiece of the tunnelling machine, to serve both as a primary support and the final tunnel lining. The annular space left between the segmental lining and the soil as the machine advances was pressure grouted during each advance. The tunnelling machine, lining segments and the procedure of erection and grouting of the lining is described, together with an indication of progress rates and performance.