关键词: 微差爆破, 地震, LS-DYNA, 加速度, 效果评价

Abstract: Millisecond blasting can create vibration environment similar to that induced by a natural earthquake. In order to better study and evaluate the simulation of natural earthquake by means of blasting method, a constitutive model which can well describe the dynamic property of soil under blasting load is built in the frame of LS-DYNA; meanwhile, the full-scale numerical simulation is implemented for an in-situ test of blast-induced ground motion in a soil field; and the simulated results are compared with test data, which validates the accuracy of numerical method. The analysis results reveal that the simulated acceleration time histories are approximate to the recorded results in the field test, so as to indicate that the numerical method can provide useful instructions beforehand for the in-situ blasting tests; furthermore, the pressure developments that haven't been recorded in the in-situ test are also obtained as well as analyzed; and the similarities and differences between blast-induced ground motion and nature earthquake are discussed too, which enriches the research on the blast-induced ground motion. The results show certain degree of effectiveness of simulating natural earthquake by blasting test, so as to supply a simple, effective and economic numerical method for simulating natural earthquake by means of millisecond blasting test.

Key words: millisecond blasting, earthquake, LS-DYNA, acceleration, effect evaluation