NONLINEAR DYNAMIC ANALYSIS OF REINFORCED CONCRETE LARGE-PANEL BUILDING

A nonlinear dynamic analysis of large-panel reinforced concrete building (LPB) using LIRA-SAPR software is presented. LPBs, which became prevalent in the mid-20th century, have generally demonstrated good seismic performance during past earthquakes. However, the connection regions and specific structural characteristics still present challenges in accurately modeling and predicting their behavior under seismic loading. Conventional linear models often inadequately represent the complex nonlinear behavior such as strength and stiffness degradation and connection failures inherent in LPBs, highlighting the need for more sophisticated analytical approaches. A detailed nonlinear analysis methodology was applied to a full-scale reinforced concrete precast LPB, investigating various parameters including material properties, damping variation, and their effects on interstory drift ratios and displacement patterns. The analysis revealed significant differences in seismic response, particularly for lower concrete grades, emphasizing the critical role of accurate material characterization. Displacement and acceleration distributions exhibited directional dependencies, aligning with results from existing literature and full-scale testing. Despite the strengths of the LIRA-SAPR software, certain limitations were identified, such as the inability to modify the standard hysteresis model, which lowers the accuracy of the simulation of strength and stiffness degradation. The findings suggest the necessity of modifying existing building codes to include specific acceptance criteria and updated analysis procedures tailored to the unique behaviors of LPBs. Such modifications are essential for developing effective tools for seismic performance evaluation and enhancing the resilience of these structures.