SMOOTH BLASTING TECHNOLOGY IN TENGZHOU TUNNEL OF BEIJING-SHANGHAI HIGH SPEED RAILWAY CONSTRUCTION

Tengzhou tunnel,part of Beijing-Shanghai high speed railway was constructed with a method of bench smooth blasting.It successfully passed the long shallow section and the complex stratum with karst caves.This paper mainly focused on the difficulties of the bench smooth blasting construction,the selection and adjustment of parameters for the typeⅡ and typeⅢ rock sections.The tunnel was finally completed ahead with safety and a high quality at the speed of 175m/month.