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http://dx.doi.org/10.12652/Ksce.2019.39.1.0013

New Approaches for Calibrating Material Factors of Reinforced Concrete Members in Korean Highway Bridge Design Code (Limit State Design) and Reliability Analysis  

Lee, Hae Sung (Seoul National University)
Song, Sang Won (Seoul National University)
Kim, Ji Hyeon (Korea Bridge Design and Engineering Research Center)
Publication Information
KSCE Journal of Civil and Environmental Engineering Research / v.39, no.1, 2019 , pp. 13-24 More about this Journal
Abstract
This paper brings up fallacy of material factors specified for the design of concrete members in the current Korean limit state design code for highway bridges, and proposes new material factors based on a robust optimization scheme to overcome the fallacy. It is shown that the current load factors in the code and the proposed material factors lead to a much higher reliability index than the target index. The load factors are adjusted to yield the target reliability index using the inverse reliability analysis. A reliability-based approach following the basic concept of Eurocode is formulated to determine material factors as well as load factors. The load-material factors obtained by the proposed reliability-based approach yield a lower reliability level than the target index. Drawbacks of the basic concept of Eurocode are discussed. It is pointed out that differences in the uncertainties between materials and members may cause the lower reliability index of concrete member than the target.
Keywords
Korean highway bridge design code; Limit state design; Reliability-based design code; Resistance factor; Material factor;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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