断层动态滑动的摩擦性质是断层力学和地震动力学中的重要问题，因为地震过程中断层的摩擦显著影响着应力降、能量分配及同震位移。近20年来，断层力学领域兴起了岩石中-高速摩擦实验研究，其目的正是在于在模拟同震阶段断层的动态摩擦滑动。为了更好地认识汶川地震高角度逆冲断层作用的动力学机制以及复杂的地表破裂和位移分布，本项目拟使用旋转剪切低速-高速摩擦实验机和新近调试完成的压力容器，对汶川地震断层带断层泥和碎裂岩样品开展孔隙水压条件下的中-高速摩擦实验研究。重点关注的科学问题包括：(1) 孔隙压力水对汶川地震断层带中-高速摩擦性质及其均一性的影响；(2) 断层岩在实验中所经历的各种物理化学变化；(3) 中速域的摩擦滑动速度依赖性；(4) 决定断层岩摩擦性状的物理机制。在此基础上，我们将本研究中的实验结果和干燥条件下的进行对比，探讨这些结果的地震动力学意义。

Frictional properties of faults in dynamic sliding are of great importance in fault mechanics and earthquake dynamics, as fault friction has significant influence on stress drop, energy budget and coseismic displacement during earthquakes. In recent 20 years, intermediate to high-velocity rock friction experiments have been launched extensively in fault mechanics studies, aiming to simulate dynamic frictional sliding of faults during coseismic stage. In order to get a better understanding on mechanisms of high-angle reverse faulting and complex surface rupture and slip distribution during the Wenchuan earthquake, we try to conduct intermediate to high-velocity friction experiments on fault gouges and cataclasites from the Wenchuan earthquake fault zone in the presence of pressurized pore water, using a rotary-shear low to high-velocity frictional testing machine equipped with a newly-tested pressure vessel. The main concerned issues include (1) the effects of pressurized pore water on intermediate to high-velocity frictional properties of the Wenchuan earthquake fault zone and their homogeneity. (2) The physico-chemical changes of the studied fault rocks during the experiments. (3) The velocity dependence of frictional sliding in the intermediate velocity regime. (4) The mechanisms controlling the frictional behaviors of fault rocks. Based on these experimental explorations, we will compare the experimental results in this study with those obtained in the air-dry condition and discuss the implications of these results for earthquake dynamics.