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Study of Reliability-Based Criteria for Seismic Design of Reinforced Concrete Frame Buildings.
Hwang, H. H. M.; Hsu, H. M.
National Science Foundation, Washington, DC., August 10, 1991, 188 p.
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The report presents reliability-based criteria for the seismic design of reinforced concrete, moment-resisting frame buildings. The authors develop these criteria in the LRFD format by considering structural strength explicitly and ductility implicitly. The proposed design criteria are established on the basis of the seismic performance of the entire frame system, since the collapse limit state employed here is determined by the flexural failure mechanism of a structural system rather than the failure of structural members. Acceptable risk levels for various categories of buildings are investigated here, and seismic load factors for ordinary buildings in various seismic zones of the United States are determined. It is shown that, in low seismicity zones and when detailed as an IMR frame as specified by ACI 318-89, frame structures designed only for dead and live loads can provide enough seismic resistance for ordinary and high risk buildings. For essential buildings, the seismic design requires use of both a seismic load factor and an importance factor of 1.0.
; Reliability; Dynamic response; Risk; Earthquake engineering; Earthquake resistant structures; Loads (Forces); Reinforced concrete; Design criteria; Concrete construction; Design standards; Mathematical models; Framed structures; Seismic waves