Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
권호 표지
DOI QR코드

DOI QR Code

Static Behavior of Stud Shear Connector for UHPC Deck

초고성능 콘크리트 바닥판을 위한 스터드 전단연결재의 정적 거동

  • Lee, Kyoung-Chan (High-speed Railroad System Research Center, Korea Railroad Research Institute) ;
  • Kwark, Jong-Won (Structural Engineering Research Division, Korea Institute of Civil Engineering and Building Technology) ;
  • Park, Sang-Hyeok (High-tech Construction Materials Center, Korea Conformity Laboratories) ;
  • Kim, Jee-Sang (Department of Civil & Architectural Engineering, Seokyeong University)
  • 이경찬 (한국철도기술연구원 고속철도연구본부) ;
  • 곽종원 (한국건설기술연구원 인프라구조연구실) ;
  • 박상혁 (한국건설생활환경시험연구원) ;
  • 김지상 (서경대학교 토목건축공학과)
  • Received : 2013.09.06
  • Accepted : 2014.04.24
  • Published : 2014.10.31
Download PDF
⟨ Previous Next ⟩

Abstract

Typical composite girder has been composed with conventional concrete deck and steel girder. Recently, ultrahigh-performance-concrete (UHPC) deck is proposed in order to enhance durability and reduce weight of deck as well as to increase stiffness and strength of the composite girder. This study investigates that a headed stud is still compatible as a shear connector for the UHPC deck and steel girder composite beam. Twelve push-out specimens are prepared to evaluate the static strength of stud shear connectors embedded in the UHPC deck. The test program proves that the static strength of the stud shear connectors embedded in UHPC well meets with design codes described in AASHTO LRFD. Chosen experimental variables are aspect ratio of height to diameter of stud, thickness of deck and thickness of concrete cover over the head of stud. From the test program, aspect ratio and cover thickness are investigated to mitigate the regulations of the existing design codes. The minimum aspect ratio and the minimum cover thickness given in AASHTO LRFD are four and 50mm, respectively. This limitation hinders to lower the thickness of the UHPC deck. The results of the experiment program give that the aspect ratio and the cover thickness can be lower down to three and 25mm, respectively. Eurocode-4 regulates characteristic relative slip at least 6mm. However, test results show that stud shear connectors embedded in UHPC provide the characteristic relative slip only about 4mm. Therefore, another measures to increase ductility of stud should be prepared.

합성보는 콘크리트 바닥판과 강재 거더로 이루어져 왔으나, 바닥판의 자중을 줄이면서 내구성을 향상시키고 나아가 교량의 강도 및 강성을 향상시키기 위하여 초고성능 콘크리트(UHPC)를 교량 바닥판으로 채용한 합성보가 최근에 제안되고 있다. 이 연구는 기존의 스터드 전단연결재가 UHPC 바닥판을 합성함에 있어 유효한지에 관하여 실험적으로 검토해보고자 한다. 12개의 push-out 시험체를 통하여 UHPC 바닥판에 매립된 스터드 전단연결재의 정적 강도를 평가하였으며, 실험 변수로 바닥판 두께, 스터드 높이 및 지름을 채택하여, 기존에 제한되었던 스터드 지름에 대한 높이의 비율인 형상비와 스터드 머리부 상부 콘크리트 피복두께의 제한을 완화하는 것이 가능한지에 대하여 검토하였다. 이 연구의 실험으로부터 기존 AASHTO LRFD에 제시된 정적 강도평가식을 UHPC에 매립된 스터드 전단연결재에 적용하는 것이 유효함을 확인하였으며, 4이상으로 제한된 형상비는 3.1까지 낮추어도 되며, 50 mm로 제한된 최소 피복두께도 25 mm까지 낮출수 있음을 확인하였다. 다만 Eurocode-4에 제시된 연성도 기준인 특성 상대슬립 6 mm 이상의 기준을 만족하지 못하여, UHPC에 매립된 스터드 전단연결재는 별도의 연성 보강 방안이 채택되지 않는다면 강성 전단연결재로 간주하여야 할 것이다.

Keywords

References

  1. Korea Institute of Construction Technology(KICT), Development of Design and Construction System Technology for Hybrid Cable Stayed Bridge, KICT 2011-076, KICT, Korea, 2011 (in Korean).
  2. Korea Concrete Institute, Design Recommendations for Ultra-High Performance Concrete K-UHPC, KCI-M-12-003, Korea, 2012 (in Korean).
  3. Yang, I. H., Joh, C., Lee, J. W., and Kim, B. S., "Torsional behavior of ultra-high performance concrete squared beams," Engineering Structures, 56, 2013, pp. 372-383. https://doi.org/10.1016/j.engstruct.2013.05.027
  4. Park, J. S., Kim, Y. J., Cho, J. R., and Jeon, S. J., "Characteristics of Strength Development of Ultra-High Performance Concrete according to Curing Condition", Journal of the Korea Concrete Institute, Vol. 25, Issue 3, 2013, pp. 295-304 (in Korean). https://doi.org/10.4334/JKCI.2013.25.3.295
  5. Yang, I. H., Joh, C., and Kim, B. S., "Flexural strength of large-scale ultra high performance concrete prestressed T-beams," Canadian Journal of Civil Engineering, 38, 2011, pp. 1185-1195. https://doi.org/10.1139/l11-078
  6. Graybeal, B. A. "Flexural Behavior of an Ultrahigh-Performance Concrete I-Girder", Journal of Bridge Engineering ASCE, Vol. 13, Issue 6, 2008, pp. 602-610. https://doi.org/10.1061/(ASCE)1084-0702(2008)13:6(602)
  7. Graybeal, B. A. "Fatigue Response in Bridge Deck Connection Composed of Field-Cast Ultra-High- Performance Concrete", Transportation Research Record 2251, 2011. pp. 93-100.
  8. John, H. and George, S., The Implementation of Full Depth UHPC Waffle Bridge Deck Panels, Federal Highway Administration Highways for LIFE Technology Partnerships Program, 2010.
  9. Harris, D. K. and Roberts-Wollmann, C. L., Characterization of the Punching Shear Capacity of Thin Ultra-High Performance Concrete Slabs, Final Report, Virginia Transportation Research Council, Charlottesville, VA, 2005.
  10. Naaman, A. E. and Chandrangsu, K., "Innovative Bridge Deck System Using High-Performance Fiber-Reinforced Cement Composites," ACI Structural Journal, Vol. 101, No. 1, Jan.-Feb., 2004, pp. 57-64.
  11. Naaman, A. E., Likhitruangsilp, V., and Parra-Montesinos, G., "Punching Shear Response of High-Performance Fiber-Reinforced Cementitious Composite Slabs," ACI Structural Journal, Vol. 104, No. 2, Mar.-Apr. 2007, pp. 170-179.
  12. Toutlemonde, F., "Fatigue Performance of UHPFRC Ribbed Slab Applied as a Road Bridge Deck Verified According to the Eurocodes," Proceedings of the 5th International Conference on Concrete under Severe Conditions, Tours, France, 2007, pp. 1191-1200.
  13. Ollgaard, J. G., Slutter, R. G., and Fisher, J. W., "Shear strength of stud connectors in lightweight and normal-weight concrete," AISC Engineering Journal, Vol. 8, Issue 2, 1971, pp. 55-64.
  14. AASHTO, AASHTO LRFD Bridge Design Specifications, 4th edition. Washington, D.C. 2007.
  15. CEN. 1994-2 Eurocode 4: Design of Composite Steel and Concrete Structures, Part 2: General rules and rules for bridges. 2005.
  16. CEN, 1994-4-4 Eurocode 4: Design of composite steel and concrete structures, Part 1-1: General rules and rules for buildings. 2004.
  17. Xu, C. and Sugiura, K., "FEM analysis of failure development of group studs shear connector under effects of concrete strength and stud dimension," Engineering Failure Analysis, in press, 10.1016/j.engfailanal.2013.02.023, available online 26 Feb. 2013.
  18. Hegger, J., Feldmann, M., Rauscher, S., and Hechler, O., "Load-Deformation Behavior of Shear Connectors in High Strength Concrete subjected to Static and Fatigue Loading." IABSE Symposium Report Budapest 2006: Responding to Tomorrow's Challenge in Structural Engineering, IABSE, 2006, pp. 17-24.