Dynamic Response of a Tunnel-Form Structure Subjected to Seismic Excitations

Abstract

The tunnel-form building system as innovative construction industry is gaining popularity and progressing increasingly towards a more effective structural system due to minimizing expenses, human resources, and construction time. In the current paper, an attempt was launched to study the dynamic response of a 5-story tunnel-from structure subjected to earthquake excitations. The seismic performance of the structure is investigated by performing incremental dynamic analysis (IDA) using a suite of 10 pairs of earthquake records. Also, the fragility curves were created based upon the results of incremental dynamic analysis as it is one of the effective methods of conducting nonlinear dynamic analyses to gather data to estimate the fragility curves. The results showed that the probabilities of exceeding the Immediate Occupancy (I.O) performance level for spandrels under both DBE and MCE hazard scenarios are less than 10 and 20%, respectively. Thusly, under both DBE and MCE hazard scenarios; these values for the walls are about 3 and less than 6%, respectively. Overall, it can be assumed that the tunnel-form structure can basically satisfy the Immediate Occupancy (I.O) performance level even under severe seismic events.