Research on Blasting Parameters of Prism Vertical Cutting
Aiming at the problem of determining the parameters of the corner-column cutting hole network,according to the previous research,the calculation model of the radius of the crushing zone Rp and the radius of the fracture zone Rf under the action of rock blasting is summarized and deduced,the effects of blast stress waves and blast gases on rock fragmentation are quantified,and according to the results of Rpand Rf combined with the effect of distending space,the calculation model of the parameters of the cut hole mesh was constructed.Combined with the actual calculation example on site,The radius of the crushing zone caused by the explosion stress wave is R1=50 mm,the radius of the crack zone is R2=550 mm,the radius of the crushing zone caused by the secondary crushing of the explosive gas is lc=16 mm,and the radius of the crack zone is lg=420 mm.Since the holes should be located in Rp=66 mm,Rf=970 mm combination with the space effect of crushing expansion,the distance between the charging hole L and the empty hole and the distance between the charging holes L1 must satisfy 66 mm＜L＜L1＜160 mm.Combined with the actual on-site L=0.1 m,L1=0.15 m.A numerical model is established for the cutting scheme to calculate,the simulation results show that the average crack length in the fissure zone is 1 069.4 mm,compared with Rf=970 mm,the error is 99.7 mm,the average length of the crushed cavity in the crushing area is 67.1 mm,and the error is only 1.1 mm compared with Rp=66 mm.The cutting scheme has been carried out for many times on-site roadway excavation experiments.The test results show that the utilization rate of the blasthole can be increased from the original 80％to more than 93％,which verifies the validity of the model.
万方数据
维普
