EVALUATION OF CURRENT NONLINEAR STATIC PROCEDURES FOR CONCRETE BUILDINGS USING RECORDED STRONG-MOTION DATA

This paper evaluates current Nonlinear Static Procedures (NSPs) specified in the FEMA-356, ASCE-41, ATC-40, and FEMA-440 documents using strong-motion data from reinforced-concrete buildings. For this purpose, peak roof (or target node) displacements estimated from the NSPs are compared with the value derived from recorded motions. It is shown that: (1) the NSPs either overestimate or underestimate the peak roof displacement for several of the buildings considered in this investigation; (2) the ASCE-41 Coefficient Method (CM), which is based on recent improvements to the FEMA-356 CM suggested in FEMA-440 document, does not necessarily provide better estimate of roof displacement; and (3) the improved FEMA-440 Capacity Spectrum Method (CSM) generally provides better estimates of peak roof displacements compared to the ATC-40 CSM. However, there is no conclusive evidence of either the CM procedures (FEMA-356 or ASCE-41) or the CSM procedure (ATC-40 or FEMA-440) leading to better estimate of the peak roof displacement when compared with the value derived from recorded motions