Quantification of modeling uncertainties for collapse assessment of structural systems under seismic excitations

Abstract eng:
This paper discusses the effect of modeling uncertainties on the collapse potential of steel moment-resisting frames using simple mathematical models denoted as “generic moment-resisting frames.” The collapse potential is represented by the probability of collapse given the value of ground motion intensity measure. In this study, collapse capacity of the structural system subjected to a single ground motion is defined as the spectral acceleration at the first mode period at which the building will become dynamically unstable. The statistical information about variation in the deterioration parameters of components of the frames are extracted from recently developed databases for component deterioration modeling. Variables studied include plastic hinge rotation capacity, post-capping rotation capacity and cyclic deterioration of components. It is shown that uncertainty in estimation of plastic hinge rotation capacity has the largest effect on uncertainty in collapse capacity of the structures studies. This uncertainty is in the order of 0.16 once plastic hinge rotation capacity is considered as the only variable parameter compared to the value of 0.20 once all three parameters are considered as uncertain. These estimates of uncertainty in collapse capacity are smaller than the values obtained by utilizing Monte Carlo simulation based on a case study of a steel moment resisting frame designed with recent seismic code provisions. The difference in results is attributed to larger P-Δ effects in generic moment resisting frames.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket