Research on seismic response analysis of slopes in nuclear power plant

Abstract

The large and complicate slopes in nuclear power plants are simplified into cylinder model and slope model with free surfaces and structural planes, then the pretreatment and input of seismic wave, setting of dynamic artificial boundaries are studied. The seismic spread, reflection, oscillation and attenuation of designed simple harmonic wave and macroseism wave are simulated and verified by dynamic theory solution. Finally, the dynamic response of slope under macroseism wave is discussed by time-history dynamic analysis. The results showed that: The seismic wave has amplification effect and reflection on the free surface of slope, the weak structural plane leads to the reflection and transmission of the seismic wave. Constraint boundary gives rise to the reflection, while viscous absorption boundary and free-field boundary eliminate the reflection. The seismic wave would come into being several reflections on the slope face, and the amplification factor increases with the increasing elevation. The amplification effect of free surface of anisotropic slope is more intense than that of isotropic slope, which increases obviously on the weak structural plane. The relative slip and permanent deformation of anisotropic slope is greater than that of isotropic slope. Anisotropic condition is detrimental to the seismic stability of slope.