SEISMIC RESPONSE ESTIMATION OF UNBONDED PRECAST PRESTRESSED CONCRETE BUILDINGS BASED ON FISHBONE-SHAPED FRAME ANALYSES

This study numerically investigates the seismic response of buildings with unbonded PCaPC beam members with fishbone-shaped frame analyses. Time history response analyses revealed that the ratio of maximum drift angles between bonded and unbonded frames ranged from 0.8 to 1.2 in 60% of cases. Notably, both equivalent linearization method and time history response analyses consistently demonstrated that unbonded frames reached limit states later than bonded frames, indicating a significant damage mitigation effect. Furthermore, response evaluations using the equivalent linearization method demonstrated comparable accuracy for both unbonded and bonded frames when compared to time history response analysis results.