The Technology Study On Long-hole Pyramid Cut Blasting In Hard Rock Vertical Shaft

In vertical shaft construction, long-hole pyramid cut blasting technology canreduce the burden area at the bottom of the hole, which can effectively restrain theholder made of rock, so as to strengthen the break and cast of rock, enhance formingthe cut cavity. This thesis mainly studies on the problem about the speed of free facerock when using the pyramid cut blasting technology in the vertical shaft construction,which impacts on the hanging scaffold device. This thesis also has a systematicanalysis of effect factors of long-hole pyramid cut blasting technology. This thesismainly researches the RHT material constitutive model, and dedue the determinationmethod of rock RHT material constitutive model. With the basic mechanical propertytests of diorite, this thesis gains the parameters of rock RHT material constitutivemodel. Using business software AUTODYN to build the half equal proportion modelof5m depth hole cut blasting, through the numerical calculation, This thesis gains thelaw of cut cavity forming and cut speed of free face rock with different number ofholes, tamping and dip angle. Finally This thesis has done a lot of tests, not onlyverifying the result of simulation，but also determining the best vertical shaft blastingproject and parameters.