Dynamic response of structures located in near-field and far-field regions using IDA and MIDA

Structural mechanics

In the current research project, an effort is made so as to investigate the capability of the innovative Modal Incremental Dynamic Analysis (MIDA) method considering 3D structural models, the effect of plan irregularities and near-field earthquake records. Therefore, to fulfil this goal, 10 near-field earthquake records in one principal direction of structures as well as 10 far-field earthquake records in two principal directions of structures are applied to 12 structures with 6, 12 and 18-storeys, and 10 %, 20 %, 30 % and 40 % plan irregularities. The study of these parameters reveals that in geometrically regular 3D structures, this innovative method meets all seismic demands parameters just as the IDA method does. Furthermore, it concludes that MIDA method is not capable of obtaining the exact IDA curves in low-rise and medium-rise structures located in near-field regions since it results in noticeable errors. Finally, it is essential to improve the MIDA approach for near-field earthquake records by replacing the drift criterion utilized in this method with a more accurate drift criterion.