Comparing X-Braces Acceptance Criteria of Steel Building code, Quick and Comprehensive Seismic Evaluation Procedures

In this paper, acceptance criteria of steel building code, comprehensive and quick evaluation procedures for X-bracing, are compared to each other parametrically and numerically. For this purpose, it is assumed first that the sample building is designed to meet steel building code and then by introducing transform parameters and using stress ratio of the designed components, acceptance of the designed building for life safety performance level is investigated. X-bracing acceptance criteria are studied using the new method and a list of differences for 2, 4, 6 & 8 story buildings is prepared in details. Results show that almost 5% of X-braced samples designed based on steel building code are rejected by comprehensive and quick seismic evaluation. On the other hand, some rejected components based on steel building code, meet comprehensive and quick evaluation procedures. Furthermore, by using a similar method and assuming that building components meet quick evaluation, their acceptance possibility by comprehensive evaluation is investigated. Based on acquired results, almost 50% of X-braces meeting quick evaluation, are rejected by comprehensive evaluation. In contrast, some rejected samples by quick evaluation meet comprehensive evaluation procedure.