The response and energy dissipation of rock under stochastic stress waves were analyzed based on dynamic fracture criterion of brittle materials integrating with Fourier transform methods of spectral analysis. When th...The response and energy dissipation of rock under stochastic stress waves were analyzed based on dynamic fracture criterion of brittle materials integrating with Fourier transform methods of spectral analysis. When the stochastic stress waves transmit through rocks, the frequency and energy ratio of harmonic components were calculated by analytical and discrete analysis methods. The stress waves in shale, malmstone and liparite were taken as examples to illustrate the proposed analysis methods. The results show the harder the rock, the less absorption of energy, the more the useless elastic waves transmitting through rock, and the narrower the cutoff frequency to fracture rock. When the whole stress energy doubles either by doubling the duration time or by increasing the amplitude of stress wave, ratio of the energy of elastic waves transmitting through rock to the whole stress energy (i.e. energy dissipation ratio) is decreased to 10%-15%. When doubling the duration time, the cutoff frequency to fracture rock remains constant. However, with the increase of the amplitude of stress wave, the cutoff frequency increases accordingly.展开更多
Based on the calculation method of information gain in the stochastic process presented by Vere-Jones, the rela tion between information gain and probability gain is studied, which is very common in earthquake predict...Based on the calculation method of information gain in the stochastic process presented by Vere-Jones, the rela tion between information gain and probability gain is studied, which is very common in earthquake prediction, and the yearly probability gain for seismic statistical model is proposed. The method is applied to the non stationary Poisson model with whole-process exponential increase and stress release model. In addition, the prediction method of stress release model is obtained based on the inverse function simulation method of stochastic variable.展开更多
基金Projects(50404010, 50574098) supported by the National Natural Science Foundation of Chinaproject(05jj10010) supported by the Hunan Provincial Natural Science Foundation of Distinguished Young Scholars
文摘The response and energy dissipation of rock under stochastic stress waves were analyzed based on dynamic fracture criterion of brittle materials integrating with Fourier transform methods of spectral analysis. When the stochastic stress waves transmit through rocks, the frequency and energy ratio of harmonic components were calculated by analytical and discrete analysis methods. The stress waves in shale, malmstone and liparite were taken as examples to illustrate the proposed analysis methods. The results show the harder the rock, the less absorption of energy, the more the useless elastic waves transmitting through rock, and the narrower the cutoff frequency to fracture rock. When the whole stress energy doubles either by doubling the duration time or by increasing the amplitude of stress wave, ratio of the energy of elastic waves transmitting through rock to the whole stress energy (i.e. energy dissipation ratio) is decreased to 10%-15%. When doubling the duration time, the cutoff frequency to fracture rock remains constant. However, with the increase of the amplitude of stress wave, the cutoff frequency increases accordingly.
文摘Based on the calculation method of information gain in the stochastic process presented by Vere-Jones, the rela tion between information gain and probability gain is studied, which is very common in earthquake prediction, and the yearly probability gain for seismic statistical model is proposed. The method is applied to the non stationary Poisson model with whole-process exponential increase and stress release model. In addition, the prediction method of stress release model is obtained based on the inverse function simulation method of stochastic variable.
