In this paper, the ANSYS software is used to simulate the effect of the surface blasting on underground chambers. The EH4 electromagnetic imaging system is employed to determine the different lithology and faults distribution of stratigraphy from roof to the ground, and the IDTS3850 tester to measure the blasting vibration data, then a linear fitting is used to analyze the particle vibration velocity attenuation law of underground chamber roof based on Sadowsky empirical formula. The LS-DYNA module of ANSYS software which provides explosive material model and JWL equation can simulate the blasting loads. The corresponding impact of blasting loads on the stability of chamber was assessed from the peak vibration velocity and stress by using Lagrange method and matched post-processing procedures LS-PREPOST. It is shown that the maximum vibration velocity in the surrounding the chamber is on the side face to the blast; under certain circumstances, although the surface blasting causes chamber displacement and wall caving phenomena, it does not affect the overall stability.
After decades of exploitation in our country, most of the open-pit mines nears the end, and transformation from open-pit to underground mining has become a trend. In order to realize the smooth transition to underground, maintain steady production scale and longer construction transition, most of the mines use the combined open pit-underground mining as the transition pattern. With the increase of underground mining, study on the stability of underground engineering is much important.
Because of the complexity and uncertainty of the rock mass, it is difficult to obtain quite accurate geological conditions and the occurrence of environmental information before construction, so the general stability evaluation method of underground chamber like field measurement method, engineering analogy method and experience forecast method, etc. are difficult to completely solve the problem in engineering practice, thus, numerical simulation analysis of field monitoring measurement is very necessary (Li et al. 2003, Singh 2002, Cui & Chen 1999). In this paper, the ANSYS software is used to simulate the effect of the surface blasting on underground chamber, in which the 15-DYNA module can process kinds of complicated nonlinear problems, its practical algorithm is especially suitable for analysis of dynamic nonlinear problem, and it can successfully simulate the explosion process of numerous media and various blasting process (Xiao 2004).