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As the mine gradually develops towards depths,the method of excavation and blasting on previous roadways in Songxian Shanjin is not applicable,and there are problems such as small excavation approach footage,low working efficiency,severe over and under break and high cost of support.Based on the rock occurrence state in Songxian Shanjin,the paper proposed controlled blasting for hard-rock large-section jumbo excavation,which uses a drilling jumbo instead of conventional ones,and can effectively improve the efficiency of the rock drilling,so that the rock drilling work can be mechanically manipulated and automated;combining a drilling jumbo with a slightly wedge hollowing at a predetermined tilt angle can not only solve the problem of drilling jumbo drilling a large wedge-shaped hole with a relatively big cutting angle when the section is small,but the problems of a conventional vertical hollowing having difficulty in hollowing out the rock and forming a large free space.It is known by controlled blasting test in Songxian Shanjin that this method is closer to the blast design section specification in terms of tunnel width and height,and the section regularity is improved;the blasting excavation approach footage is improved,the rate of ore bulkiness is reduced,and the economic benefit is better.