The shear stress on smooth blasting of pipe protecting borehole wall between free face and protecting face reaches as high as 3.

Dynamic photo elasticity experiment is conducted,and the isochromatic fringes graphs in the process of smooth blasting of pipe protecting borehole wall is obtained.

Application of double-pipe protecting borehole wall blasting in development laneway of Qingping Phosphate Mine;

To study single hole-unilateral protecting borehole wall blasting,cement mortar model tests were carried out.

This paper introduced the principle and method of protecting borehole wall blasting and its application in the Dongxia and Weifang coal mine.

Controlled smooth blasting technology applied to seam gateway and semi coal-rock roadway in Shouli Mine;

The research on the application of smooth blasting in fast excavation;

Application of smooth blasting one-step forming technology in drift driving for large-sized section;

The technology problems of blasthole depth,cutting blasting,smooth wall blasting,and directional blasting is discussed.

Adopting smooth wall blasting in excavation can reduce the vibration and the fracture to the surrounding rock, also it can guarantee the surrounding rock's perfection and stability.

Based on the smooth wall blasting technigue,smooth wall pipe split blasting technique is presented and the possibility, function and advantage of the method is confirmed by experiment,which contributed functional basis for effectivly managing the roof of under ground station and underground road rock of the gold min

Factors affecting smooth surface blasting;

This article is detailed to introduce the principle,the method of smooth surface blasting,the choice of the parameter of smooth surface blasting,the standard and the advantage of smooth surface blasting,explaining the necessity of adopting smooth surface blasting.

At present,the application of smooth surface blasting for hydraulic tunnel becomes more and more popular.