Cross-section design of nuclear power plant buildings satisfying target floor response spectrum

• Proposed a method to estimate shear cross-section for target floor response spectrum. • Introduced the “allowable spectrum” concept for efficient cross-section optimization. • Mitigated excessive cross-section growth by accounting for weight variations. • Reduced initial floor response using the modal iteration error correction method. In this study, we proposed a method to estimate the shear cross-sectional distribution to achieve the desired floor response spectrum. The calculation process and analysis conditions were explicitly defined, and multiple illustrative examples were presented to validate the approach. The methodology was based on the modal iteration error correction method for inverse analysis. The target acceleration response spectrum was calculated for the mass point of the internal concrete building, with the target value set at half of its initial value. The design variable was the shear cross-section of the internal concrete building. When weight variations were considered, the excessive growth of the target cross-section was effectively mitigated. Furthermore, the concept of an “allowable spectrum” was introduced. The findings revealed that employing the allowable spectrum enabled a more efficient search for the optimal cross-section compared to the conventional target spectrum. Therefore, the proposed technique successfully determines the shear cross-sectional distribution, substantially reducing the initial floor response.