EARTHQUAKE ANALYSIS OF CONCRETE GRAVITY DAMS INCLUDING BASE SLIDING

A numerical method, the hybrid frequency-time domain (HFTD) procedure, is used to compute the earthquake response of concrete gravity darns, including sliding along the interface between the dam base and the foundation rock. The solution procedure accounts for the non-linear base sliding behaviour and the frequency-dependent response of the impounded water and flexible foundation rock. A Coulomb friction model represents the force-displacement relationship for sliding at the base interface. Using the solution procedure, an analysis of a typical dam (122 m high) shows that base sliding will occur during a moderate earthquake but the sliding displacement will be a tolerable amount when dam-foundation rock interaction is considered.