b'Seismic and Cost AssessmentAdvancing understanding of the non-linear seismic behavior of deeply of Deeply Embedded orembedded advanced reactors to ensure their safe and cost-effective construction Buried Advanced Rectors withand operation.Seismic Isolation Strategies A dvanced nuclear power plants are being proposed with deeply embedded or buried reactor buildings. This approach stems from the technical and economic expectations that the overall safety of the plants will increase, while decreasing the cost by eliminating bulky shielding walls and structural dimensions. Along with deeply embedding the next-generation nuclear power plants, seismic isolators are considered for their unique safety and cost benefits to the systems, structures, and components. Currently, the performance of TOTAL APPROVED AMOUNT:deeply embedded reactor buildings with or without seismic isolations is not well $1,120,500 over 3 years understood, especially under non-linear dynamic seismic environments.PROJECT NUMBER:This study investigated the seismic performance of deeply embedded advanced 19A39-029 reactor concepts with different embedment depths of reactor buildings. The PRINCIPAL INVESTIGATOR:embedment ratios (embedment depth/reactor building height) were 0%, 25%, Efe Kurt 50%, 75%, and 100%. Three-dimensional non-linear time-domain analyses were conducted for these embedment ratios with high nonlinearities in the soil while CO-INVESTIGATOR: including the geometric nonlinearities occurring at the contact-interface region. Justin Coleman, INL The study focused on isolating safety-critical components using either lead-rubber COLLABORATOR: or friction pendulum isolation. Small-scale physical experiments were conducted Purdue University for the benchmark analysis of the interface behavior between the structures and the surrounding soil. Stochastic simulations were conducted to evaluate the most important soil material parameters in dynamic simulations.(a) Cut-away of the model with water explicitly modeled. (b) Cut-away of the model with the embedded structure.26'