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| EXPERIMENTAL STUDY OF INFLUENTIAL RULE OF FRACTAL INTERCEPT ON ENERGY DISSIPATION OF STRESS WAVE |
| LI Yexue1，2，PENG Qi 3，ZHU Jianbo3，LIU Jianfeng2 |
(1. School of Civil Engineering and Architecture，Xiangfan University，Xiangfan，Hubei 441053，China；2. State Key
Laboratory of Hydraulics and Mountain River Engineering，Sichuan University，Chengdu，Sichuan 610065，China；
3. Laboratory for Rock Mechanics(LMR)，Ecoloe Ploytechnique Federale de Lausanne，Lausanne，Switzerland CH1015) |
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Abstract Scanning experiment of rough fracture and impacting dynamics test of jointed granite is respectively conducted in order to investigate influential rule of geometrical characteristic of joint surface on energy dissipation of stress wave and establish quantitative relationship between fractal intercept and energy dissipation ratio contributed by intercept of stress wave across joint on the condition of fractal dimension 2.0≤D≤2.2. It is shown that contribution towards total energy dissipation ratio from fractal dimension is still primary；but in the interval，its contribution towards total energy dissipation ratio is constant and increment of total energy dissipation ratio is decided by fractal intercept. Energy dissipation ratio which is contributed by intercept of jointed rock decreases nonlinearly with the increasing of fractal intercept. By mechanism analysis，it is indicated that on the condition of similar impact loading，smaller shear displacement leads to less work and corresponding lower energy dissipation of stress wave because larger fractal intercept corresponds to higher shear stiffness. From microscopic view，during impacting loading，sample with larger fractal intercept brings lower probability of tiny plastic strain，crystal cracking，mutual impingement among molecule，so energy of stress wave is less dissipated.
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Received: 03 August 2010
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2011, Vol. 30 
