A preliminary study on the dynamic friction behavior of concrete sliding under external excitation

Different from soil slope, the failure of rock slope destroyed along weak plane. Accordantly, block sliding method for these slope stable analysis was be devised by Newmark in 1965. A new point “critical acceleration” was devised in block sliding method; when block acceleration induced by earthquake exceed the “critical acceleration” of the sliding interface, the permanent displacement of sliding block was happened. However, in the method, “critical acceleration” derived from static force equilibrium was assumed to be a constant. The “critical acceleration” determined by peak friction angle could resulted the underestimate of permanent block sliding displacement; the “critical acceleration” determined by residual friction angle could resulted the overestimate of permanent displacement. Base on block sliding method, in this study, there were series experiments by using shake table. At first, to compare the instantaneous static friction angle of block obtained from shake table experiment and static friction angle obtained from tilt test, and then to investigate the influence of block frictional behavior by following factor: frequency of base vibration, normal stress of block, material of block. In this study, the instantaneous static friction angle of block was affected by frequency of base vibration and normal stress of block under dynamic shaking condition. When the frequency of base vibration was higher, the instantaneous static friction angle of block was higher; the instantaneous static friction angle of block reduced when the normal stress of block increased.