| In this paper, based on classic stochastic vibration theory, combined with large field measured data, the subject investigated are building structures in blasting vibration field. The main work is:Firstly, mathematical characteristic of stochastic process are analyzed theoretically, a general interference mode of structure stochastic ground vibration is obtained; then, by analyzing measured blasting ground vibration data, some characteristics of blasting seismic velocity and acceleration are got. Combined with previous research results, distribution characteristic of blasting seismic spectral energy are also obtained, and acceleration stochastic interference mode of blasting seismic is established.Secondly, because of too much factors affecting blasting seismic characteristic, blasting seismic wave has great randomness, so blasting seismic can be seen as stochastic process. Concerning that, structure damage by blasting seismic is caused by superposed of various frequency channel and different energy wave forms, so spectrum and energy characteristics of blasting seismic wave are important factors affecting structure response. This paper, applying classic stochastic process theory, artificial simulation of blasting seismic wave is put into effect by Matlab program.Thirdly, assuming blasting seismic acceleration history is stochastic process, stochastic vibration response of structure is analyzed theoretically. Damage criterion of structure by blasting seismic is fixed, and dynamic reliability calculation method of structure by blasting seismic action is obtained.Finally, stochastic vibration analysis of a two-floor frame structure by blasting seismic action is done by finite element program ANSYS. In order to contrast, that by nature seismic action is also done here, and displacement field, velocity field and stress field of this two kind of condition are obtained, and differences of the structure damage mechanics by two kind of action are analyzed.
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