| Title |
New Approaches for Calibrating Material Factors of Reinforced Concrete Members in Korean Highway Bridge Design Code (Limit State Design) and Reliability Analysis |
| Authors |
이해성(Lee, Hae Sung) ; 송상원(Song, Sang Won) ; 김지현(Kim, Ji Hyeon) |
| DOI |
https://doi.org/10.12652/Ksce.2019.39.1.0013 |
| Keywords |
도로교설계기준;한계상태설계법;신뢰도기반 설계기준;저항계수;재료계수 Korean highway bridge design code;Limit state design;Reliability-based design code;Resistance factor;Material factor |
| 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. |