The Research And Application Of Smooth Blasting Technology In Unstable Rock Mass Drivage

During the development of tunnel drivage of many domestic gold mine such as Jiaojia Gold Mine in Shandong Province, encountered a lot of unstable rock mass, The rock mass is mainly disruption and alteration granite, Rock's structure growth and many crevasse surface, and rugged coefficient is f=4～5, It belongs to IV kide unstable wall rock. If using ordinary blasting, rock is extremely easy to collapse, It can bring to the tunneling is very great difficulties and potential safety problems. From angle embarking of the author is advantageous to maintain the tunnel, Comprehensively researched to the smooth blasting technology of the underground unstable rock mass. Using explosives stress wave and rock fracture mechanics theory, researched about the cracking mechanism(opening the crack,Expansion,Fracture-arrest) of smooth blasting, On the basis of analysising smooth blasting's cracking mechanism, Inferred theoretical calculation formula of smooth blasting's Peripheral parameters. The initial pressure and quasi-static pressure of the hole wall was deduced with detonation wave theory when smooth blasting charged with air cushion, Have analyzed not coupling coefficient size to influence the effect of smooth blasting, Obtained the best not coupling coefficient without the squash area. Simultaneously has analyzed the factors of impacting smooth blasting's effect and proposed the effective regulatory measures. In theoretical analysis foundation, Combined the smooth blasting industrial test in the North tunnel of Jiaojia Gold Mine and used the multi-objective grey situation theory, Optimized a group to suit the spiral cutting ways and the smooth blasting parameters of Jiaojia gold mine's unstable rock drivage(the best smooth blasting parameters: E=450mm, W=550mm, q=0.22kg/m) . Through the experiment and application of using whole cross section smooth blasting in Jiaojia Gold Mine's unstable rock mass, It can obtain the good smooth blasting effect, And Controll overbreak quantity,the tunnel forming quality is good,driving fast,the construction security is high.So, The research results of this paper can provide the beneficial reference for Similar smooth blasting construction in the unstable rock tunnel.