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Abstract The dynamic properties of quartz mica schist are complex and it is hard to determine the blasting parameter accurately. A lot of undesirable phenomena appear during the construction，i.e. the short advance per attack，overbreak and underbreak，which lead to the low efficiency. Through the indoor experiment of split Hopkinson pressure bar(SHPB)，the elastic modulus of quartz mica schist was found to change a little with the increase of strain rate in the linear elastic stage. In the nonlinear stage，the yielding characteristics similar to those of metal material occurred. The dynamic strength increased exponentially with the strain rate. Under the impact load，quartz mica schist was broken into the flake structure along the bedding direction，exhibiting the compressive-shearing failure mode. The broken degree was related with the strain rate. The breaking energy was linearly related to the incident energy. The breaking energy density increased with the increase of strain rate with a relation of a power function. The blasting process of a single hole with the diameters of aperture and explosive of 42 and 32 mm respectively was simulated. The time of forming blasting cavity and crack was about 0.904 8 ms. The radius of blasting cavity was 13.8 cm and 4.45 times the radius of the hole. The longest fracture was 71.3 cm in length and was 23 times the radius of the hole. The fracture zone was divided into 3 areas including a serious ruptured zone，a middle ruptured zone and a slightly fractured zone. The explosive pressure was reduced exponentially and was low in the distance of the 40 cm from the explosion center. The plastic zone was 49.3 cm in radius. The value of cuthole blasting parameters of an underground cavern of actual mica quartz schist was proposed.
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2015, Vol. 34 
