Journal of the Korea institute for structural maintenance and inspection (한국구조물진단유지관리공학회 논문집)

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
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Analysis of Live Load Factor for Bridge Evaluation Through Reliability Based Load Factor Calibration

신뢰도기반 하중계수 캘리브레이션을 통한 교량 평가 활하중계수 분석

  • Received : 2022.11.10
  • Accepted : 2022.12.11
  • Published : 2022.12.31
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Abstract

In this paper, the evaluation procedure applying the limit state design method is studied to be consistent with the newly issued bridge design code in Korea. The live load factor for evaluation is proposed by calibrating for the target reliability index through reliability analysis. Using the actual bridge information collected for the representative bridge types in Korea, the load effects of the design live loads for the previous and current design codes are calculated and compared. The live load factor is calibrated through reliability analysis using the minimum required strength which equals to the load effect obtained for the example bridge. Bridge evaluation is performed by applying the live load factors for the evaluation level as well as design level. The load rating result is generally increased by applying the limit state design method compared to the previous design method and applying the proposed load factor for lowered target reliability index further increased the rating result.

이 연구에서는 국내 도로교량 평가에서도 설계와 일관성이 있도록 한계상태설계법에 상응하는 평가방법을 마련하고, 선진국과 같이 평가에서 목표신뢰도지수를 감소시키는 경우 신뢰도분석을 통하여 보정하여 평가 활하중계수를 제안한다. 국내 대표 교량형식을 대상으로 수집한 실교량 자료를 활용하여 각 설계기준 별 설계활하중에 대한 하중효과를 산정하여 비교한다. 현행 설계법에 의해 산정된 하중효과를 바탕으로 최소요구강도를 산정하여 이에 대한 신뢰도분석을 통해 활하중계수 보정을 수행한다. 설계수준에 비하여 낮춰진 평가수준의 활하중계수를 교량 안전성평가를 수행하고, 이전 설계법의 안전성평가 결과와 비교하여 평가결과가 증가함을 확인하였다.

Keywords

References

  1. Ministry of Land, Transport and Maritime Affairs (2010), Highway Bridge Design Code, MLTM.
  2. Ministry of Land, Infrastructure and Transport (2021), Bridge Design Code: KDS 24 00 00 Bridge Design Load, Korea Construction Standards Center.
  3. Korea Infrastructure Safety Corporation. (2021), Detailed Guidelines for Safety and Maintenance of Facilities (Performance evaluation), KISC.
  4. American Association of State Highway and Transportation Officials (AASHTO). (2020), AASHTO LRFD Bridge Design Specifications, AASHTO, Washington, D.C.
  5. American Association of State Highway and Transportation Officials (AASHTO). (2003), Manual for Condition Evaluation and Load and Resistance Factor Rating (LRFR) of Highway Bridges, AASHTO, Washington, D.C.
  6. Transportation Officials, Subcommittee on Bridges. (2018), The manual for bridge evaluation, AASHTO.
  7. Canadian Standard Association. (2019), Canadian Highway Bridge Design Code (CSA S6:19), Ontario, Canada.
  8. Nowak, A. S. and Collins, K. R. (2000), Reliability of Structures, McGraw-Hill.
  9. Rackwitz, R., and Fiessler, B. (1978), Structural reliability under combined random load sequences. Computers & Structures, 9(5), 489-494. https://doi.org/10.1016/0045-7949(78)90046-9
  10. Paik, I., Hwang, E. S., and Shin, S. (2009), Reliability analysis of concrete bridges designed with material and member resistance factors, Computers and Concrete, 6(1), 59-78. https://doi.org/10.12989/cac.2009.6.1.059
  11. Shin, D. K., Kim, C. Y., & Paik, I. Y. (2006), Reliability analysis of composite girder designed by LRFD method for positive flexure, KSCE Journal of Civil and Environmental Engineering Research, 26(3A), 539-546. https://doi.org/10.12652/KSCE.2006.26.3A.539
  12. Bae, C. (2016), Determination of the load-resistance factors for reliability-based codes by optimization, Doctoral dissertation, Master thesis, Seoul National University, Seoul, South Korea, 26.
  13. Nowak, A. S. (1999), Calibration of LRFD Bridge Design Code, NCHRP Report 368, Transportation Research Board, Washington, D.C., 9-28.
  14. Hwang, E. S. (2009), Development of Vehicular Load Model using Heavy Truck Weight Distribution (I), (II)(in Korean), Journal of the Korean Society of Civil Engineers, 29(3), 189-197(I), 199-207(II).