Abstract: The phenomenon of overexcavation and underexcavation of ordinary blasting tunnels is obvious,and the surrounding rock is seriously damaged,which makes the roadway roof and side siding management (prying and supporting) more difficult,and the safety of the roof slab is threatened.In order to effectively curb the hidden dangers of roof collapse and reduce the cost of roadway construction and maintenance,the application of smooth blasting can effectively control the surrounding contours and maintain the stability of the surrounding rock.In the actual construction of Dahongshan Iron Mine,the blasting parameters are continuously optimized and the roof collapses.The hidden dangers of partial favoring have been greatly reduced,which effectively reduces the risk of safety management and control,and at the same time reduces the engineering cost,thereby creating better economic and social benefits.

Key words: ordinary blasting,smooth blasting,tunnel stability,control safety risk