Functionally adaptable isolated structures for small modular reactors based on design demands

Abstract

Nuclear power plants are gradually trending toward miniaturization and standardization owing to their expensive costs, lengthy design cycles, challenging siting, and hazardous issues. However, this development presents challenges such as reduced site adaptability and weakened seismic capacity. In response to the above challenges, this paper proposes a multifunctional combination-rail tension friction slip isolator (MC-RTFSI). Its application enables small modular reactors (SMRs) to satisfy the requirements of different sites and seismic intensities without the necessity of modifying the design. MC-RTFSI is a composite system comprising different types of sliding rails that exhibit distinct mechanical properties. The selection of suitable rails is based on the specific characteristics of different sites. Furthermore, it exhibits performance decoupling in both orthogonal directions and uplift-restraining properties. Various combinations of MC-RTFSI were mechanically investigated, leading to the construction of a mechanical hysteresis model. This model was subsequently simulated by employing series–parallel combinations of nonlinear units in current finite element analysis software (ETABS, SAP 2000). Based on the result of the refined finite element simulation, the effectiveness of the simulated units is confirmed. A number of nonlinear response history analyses were conducted. The results indicate that novel isolated structures for small-scale nuclear power plants possess the capacity to perform various activities and may be adapted to accommodate different sites and ground motion characteristics.