Abstract:Difficulties are fetched in excavation of No.2 and No.3 large scale tunnels of Anchu highway,becausethey are all excavated in fractured formations.For keeping successfull progess,tunnelling techniques of light shocking,weak explosion,short step facedrift,arch prior to wall forming,supporting by long pipe shieldd vs pregroutingcombining with grid arch steel,and rock measuring technology,supportting techniques,of spraygrouting-anchoring-netting-spraygrorting are used.