Effects of slip and separation on seismic SSI response of nuclear reactor building

The seismic soil–structure interaction response of a nuclear reactor building requires modeling of the soil–structure interface. It allows slip and separation at the interface that affects the behavior and response of the reactor. The joint elements used to model the soil–structure interface, require incorporation of appropriate joint stiffness so that slip and separation phenomena take place under the warranted conditions. This slip and separation causes change in the response of the structure. This paper duly addresses the related aspects through comparative study of responses and draws important conclusions useful for design of nuclear reactor building.

Research highlights▶ Slip and separation at soil–structure interface causes stress redistribution in the soil and structure around the interface signifying the importance of modeling the interface. ▶ Tensile stresses increase with the increase of coefficient of friction at the interface in Model-2. However, these stresses may be more or less than those obtained from Model-1 depending on the coefficient of friction at the interface. ▶ Incorporation of appropriate joint stiffness is important as the overall response depends also on the stiffness contribution of the interface.