关键词: equations of motion, boundary conditions, incremental rates, polar continua

Abstract: Overturning is one of principal failure types of caisson breakwaters and is an essential content of stability examination in caisson breakwater design. The mass-springdashpot model of caisson-foundation system is used to simulate the vibrating-uplift rocking  motion of caisson under various types of breaking wave impact forces, i. e., single peak impact force, double peak impact force, and shock-damping oscillation impact force. The effects of various breaking wave types and the uplift rocking motion on dynamic response behaviors of caisson breaknvaters are investigated. It is shown that the dynamic responses of a caisson are significantly different under different types of breaking wave impact forces even when the amplitudes of impact forces are equal. Though the rotation of a caisson is larger due to the uplift rocking motion, the displacement, the sliding force and the overtuming moment of the caisson are significantly reduced. It provides the theoretical base for the design idea that the uplift rocking motion of caisson is allowed in design.

Key words: equations of motion, boundary conditions, incremental rates, polar continua