Effects of dynamic friction on sliding behavior of block in DDA
It is well known that the friction coefficient depends on the displacement and velocity. However, the current DDA program detects the slide at the contact surface by the Mohr-Coulomb criteria. Although DDA analysis is dynamic analysis, the friction coefficient is treated as a constant value. It is in fact that the sliding velocity along the fault is very high;in order of 1m/sec. Consequently, an implementation that considers the effect of dynamic friction should be employed in the DDA program especially in case of analysis the ground deformation by fault movement. This paper presents the effect of dynamic friction that should be implemented in DDA program. The validation of DDA program was firstly performed by verifying the block sliding induced by a sinusoidal motion. Subsequently, the potential rotation of block depends on the geometry and friction at contact surface was observed. Likewise, the constitutive friction law of dynamics friction developed by Dieterich (1979) and Ruina (1983) provided a connection between friction-velocity and time dependence, was used to observe the effects of weakening-friction behaviour. The analysis results showed that the effect of dynamic friction is influenced significantly in case of large slip velocity and slip distance. However, this weakening of sliding resistance may depend on many other factors such as the stiffness of the system, stress, temperature, historical sliding, etc.
DDA Dynamic friction Constitutive friction law Block sliding
P.H.DONG OSADA M.
Graduate School of Science and Engineering, Saitama University, Japan Geosphere Research Institute, Saitama University, Japan
国际会议
北京
英文
129-134
2007-08-14（万方平台首次上网日期，不代表论文的发表时间）