The design is done by first identifying the “active” ground motion and attaining the design for that record. Once this design is achieved, the performance of the damped structure is evaluated for the remaining records in the ensemble. If the damping for this ground motion violates constraints of other records in the ensemble, the ground motion for which maxi (pii > receives the largest value is added until an appropriate solution for the whole ensemble is reached.
The methodology is thus comprised of four main stages. These stages will be described in detail subsequently and are summarized as:
Stage 1. Select the “active” ground motion.
Stage 2. Attain the design for the records within the active set using the analysis redesign approach. Stage 3. Apply the remaining records in the ensemble on the current design for feasibility check and go to Stage 2 if stopping criteria are not met.
Stage 4. Stop.