Seismic Performance Analysis and Structural Optimization Design of a Science and Innovation Building in a Certain University

This study presents a comprehensive seismic performance assessment and performance-based seismic design (PBSD) optimization for a 21-story Science and Innovation Building with three basement levels, characterized by pronounced plan and vertical irregularities. An engineering-oriented PBSD framework was established, integrating irregularity identification, nonlinear time-history analysis, performance target definition, and energy dissipation evaluation. Comparative analyses between the actual and modified structural models indicate that skip-floor columns have negligible effects on the global stiffness, vibration periods, and interstory drift ratios, suggesting that they should not be classified as independent irregularities. Nonlinear time-history analyses under rare earthquakes confirm that the tower maintains overall stability, with maximum interstory drift ratios of 1/149 and 1/150 in the X and Y directions, respectively. The core tube acts as the primary energy-dissipation component, while the outer frame remains mostly elastic, forming a dual defense system of “core-tube dissipation and frame protection.” Buckling and PBSD verifications demonstrate that skip-floor columns remain elastic under rare earthquakes, satisfying both strength and deformation limits. For the podium, elastic and elastoplastic analyses using multiple software platforms show consistent responses, revealing that more than 80% of the input seismic energy is dissipated through material hysteresis. In addition, a practical construction sequence based on the recommended design is proposed to facilitate implementation and enhance engineering applicability. The proposed PBSD modeling and optimization framework provides a practical and replicable methodology for evaluating and enhancing the seismic performance of irregular high-rise buildings with discontinuous vertical systems.