Papers by Author: Song Lin Xu

Abstract: The rock is assumed to be assembled by a great number of HMUs. The number of HMUs responding to external force is uncertain, which leads to the instability of hysteretic loops. Transition probability of HMUs to the external force and temperature varies with external loading frequency and temperature. The self-adaptive adjustment effects for rocks in frequency field are obtained by uniaxial and triaxial cyclic loading: when frequency increases, transition probability of the response of mesoscopic structure to applied loads reduces, the adjustment time of self-adaptive process becomes shorter, residual strain become smaller, and hysteretic loops tend to be easy to be stable. The self-adaptive adjustment effects in temperature field can also be obtained.

Abstract: Some preliminary experiments are conducted to investigate the responses of granite， marble and red stone in the states of natural，water-saturation and oil-saturated under the shock of short pulse laser. The 3D contour of ablation pit and the preliminary relations of the ablation contour to the number of laser pulses are obtained. The results show that some cracks generate at local places for the shock of laser，and the degree of ablation of the oil-saturated rocks is more severe than that of the natural and water saturated rocks. However，further work should be conducted to control the direction，sizes and number of cracks generated under the shock of laser.

Abstract: As the rocks were composed of many minerals, high temperature might lead to the non-consistent deformation among these components. That was the mechanism of thermal damage. In the present paper, the thermal damage of rocks was investigated under a much broader temperature range until minerals phase transition. The experimental techniques of AE and the internal friction were proven to be the most useful tools to reveal the thermal damage. The affection of thermal damage to Kaiser Effect of temperature and the coupled effects of thermal and mechanical damage were also discussed.