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Abstract Explosive load of individual blasting and multiple-hole simultaneous blasting in rockmass with column charging has been analyzed based on information of construction site at Lingdong Nuclear Power Station(LNPS)，Guangdong Province，China. The blasting progress is simulated via JWL equation of state for high explosives. And the rockmass in environment with high pressure and high strain rate induced by blasting is considered as an isotropic and kinematic hardening plasticity material including rate effects. Propagation characteristics of blast-induced stress waves have been achieved using explicit dynamic analysis code LS-DYNA. The attenuation characteristics of maximum pressure of targets in rock have been analyzed. It is reported that the numerical simulation results agree well with those from theoretical calculation. Based on maximum pressure of rock in crushed zone induced by blasting with different charging weights，the variation characteristics of blasting load with charging weight with individual blasting and multiple-hole simultaneous blasting are studied. It is noted that in region around charging holes，the maximum pressure decreases rapidly with distance from charge center. Peak compressive stress and peak tensile stress both increase with charging weight. It is also suggested that the blasting load is more sensitive to single charge weight than maximum charging weight per delay in multiple-hole blasting. For this case，it is helpful to reduce the blasting vibration when blasting with more charge holes and less charge weight.
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Received: 28 April 2007
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