A new efficient method for determining the collapse margin ratio using parallel computing

The collapse margin ratio (CMR) is an important value in the FEMA P-695 process. However, determination of the CMR is computationally intensive and the duration for running a full incremental dynamic analysis (IDA) using serial computing to calculate the CMR can be prohibitive. In response to this restriction, a new efficient search method was created for finding the collapse margin ratio for a structural model using parallel computing. The proposed method does not require a full IDA and provides a significant decrease in the time required to determine the CMR compared to running a full IDA using serial computing. The new method is compared against similar methods for finding the CMR in parallel using both a four-story buckling restrained braced frame and a four-story steel moment resisting frame. Recommendations for overcoming convergence issues are discussed to aid in the application of the search method. (C) 2014 Elsevier Ltd. All rights reserved.