Journal of Korean Society of Steel Construction (한국강구조학회 논문집)

Korean Society of Steel Construction (한국강구조학회)
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Study on Fatigue Behavior and Rehabilitation of Stringer with Coped Section(I) -Experimental Study on Static and Fatigue Behavior-

절취부를 갖는 세로보의 피로거동과 보수·보강에 관한 연구(I) -정적거동 및 피로거동의 실험적 고찰-

  • Received : 1997.10.01
  • Published : 1997.09.30
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Abstract

This study encompasses the performance of static and fatigue test for the 8 large scale test specimens to clarify the fatigue behavior of coped stringer and the effect of the repair and strengthening on the damaged stringer of the floor system in steel railway bridges. For the purpose of the research, the actual stress wave for the existing bridge was measured, the basic stress range frequency histogram was made and the equivalent stress range was calculated. Using the result from the equivalent stress range made by adjusting the stress range, the static and fatigue test was carried out by identifying the previous rehabilitation and after. As the result of the static tests, it was revealed that the level of local stress under the S1 specimen test of the real equivalent stress range was similar to tensile strength of the test material, and it was consistent with the requirement of the initiation condition of the fatigue crack. Through the various rehabilitation methods to the damaged specimens, the effects of the repair and reinforcement were analyzed. According to the results of the repair of effect, bolting the high tension bolt over the stop hole was confirmed to be more adequate method than drilling only stop hole to delay the fatigue crack growth. Futhermore, in case of the stringer subjected by bending moment, the reinforcement over the upper flange side was determined to be a useful strengthening method, and the reinforcement to the web of the stringer was not appropriate to accomodate as a adequate strengthening method. Also it was confirmed that the category of the fatigue design for the coped stringer met with the category E specified on the fatigue design criteria of the Highway Standard Specification in Korea.

절취된 세로보를 갖는 강철도교량의 바닥판에서의 피로거동 및 손상시 보수 보강의 효과를 연구하기 위해 8개 대형시험체에 대한 모형시험을 수행하였다. 실교량을 대상으로 실동응력을 측정하여 기본 응력범위 빈도히스토그램을 작성하고 이에 의한 변동응력의 등가응력범위를 산출하였다. 이 등가응력범위를 기준으로 피로시험의 응력변동범위의 크기를 조정하면서 정적 및 피로시험을 보강전과 보수 보강후로 구분하여 실시하였다. 정적시험에 의하면 재하하중의 크기가 등가실동응력 수준인 시험체의 경우에서 이미 허용응력과 비슷한 응력을 나타내므로서 피로균열의 발생조건을 충족하고 있었다. 손상된 시험체에 대해 다양한 보수 및 보강을 실시하여, 각각의 결과를 비교검토하였다. 그 결과 보수효과는 stop hole을 천공하고 고장력볼트를 체결한 경우에 피로균열성장의 지체효과가 뚜렷하게 나타났다. 한편 보강효과는 휨의 지배를 받는 세로보의 경우 인장측 플랜지의 보강이 효과적이며, 복부의 보강은 보강방법으로 적절하지 않음을 알 수 있었다. 또한 직각절취된 세로보의 피로설계등급은 우리나라 시방서 피로설계규정의 E등급에 해당한다는 것을 확인할 수 있었다.

Keywords

References

  1. Struct. Eng./Earthquake Eng. v.4 no.2 Stress Reduction for Fatigue Assessment of Highway Bridges Miki, C.;Toyofuku, T.;Yoshimura, Y.;Murakoshi, J.
  2. 構造工學論文集 v.37 A 鋼プレ一トガ一ダ一橋における應力測定結果に關する報告 藤原捻;村越潤;鹿島久義
  3. Proc. of JSCE. no.356/I-3 Computer Simulation on the Fatigue Load and Fatigue Design of Highway Bridges Miki, C.;Goto, Y.;Yoshimura, Y.;Mori, T.
  4. 構造工學論文集 v.37 A 鋼橋部材交差部に生じる局部應力の發生メヵニズムと要因分析 館石和雄;竹之內博行;三木千壽
  5. Proc. of JSCE Struc. Eng./Earthquake Eng. v.2 no.2 Studies on Fatigue Damages Based on Strain Measurements of a Highway Bridges Kato, S.;Yoshikawa, O.;Terada, H.;Matsumoto, Y.
  6. Fatigue Cracking of Steel Bridge Structures(II), FHWA-RD-89-169 Fisher, John W.;Yen, Ben T.;Wang, Dayi
  7. Engineering Fracture Mechanics v.20 no.3 Stress Analysis of Strip with a Step and a Crack Norio Hasebe;Sei Matsuura;Nobuyuki Kondo
  8. J. of Struct. Div. v.103 no.2 Rapid Calculation of Stress Intensity Factors Pedro Albrecht;Kentaro Yamada
  9. J. of Struct. Eng. v.116 no.9 Fatigue Strength of Coped Steel Beams Yam, Michael C.H.;Cheng, J.J. Rojer
  10. Structural Eng./Earthquake Eng. v.5 no.1 Local Stresses at Cross Beam Connections of Plate Girder Bridges Ichro Okura;Masao Yubisui;Hiroshi Hirano;Yuhshi Fukumoto
  11. Structural Eng./Earthquake Eng. v.6 no.2 Structural Parameters Governing Fatigue Cracking in Highway Bridges Ichro Okura;Hiroyuki Takikawa;Yuhshi Fukumoto
  12. 日本土木學會論文集 no.392/I-9 ウェブガセツト溶接繼水の應力解析と疲勞壽命豫測 竹名興英;川上博道;伊藤文夫;三木千壽
  13. Int. J. of Fatigue v.19 no.1 Stress Concentration Factors for Shoulder Fillets in Round and Flat Bars under Various Loads Nao-Aki Noda;Yasushi Takase;Keiji Monda
  14. Int. J. of Fatigue v.18 no.4 Fatigue Damage Calculation in Stress Concentration Fields under Variable Uniaxial Stress Duprat, D.;Davy, A.;Boetsch, R.;Boudet, R.
  15. Fracture and Fatigue Control in Structures-Application of Fracture Mechanics Barsom, J.M.;Rolfe, S.T.
  16. 한강철교 정밀 안전진단 보고서, 연구보고서 장동일(등)
  17. Fundamentals of Metal Fatigue Analysis Bannantine, Julie A.;Comer, Jess J.;Handlock, James L.
  18. 鋼橋の疲勞 大倉一郞
  19. The Stress Analysis of Cracks Handbook Tada, H.;Paris, P.C.;Irwin, G.R.
  20. Trans. ASME, Series D. v.85 no.4 A Critical Analysis of Crack Propagation Laws Paris, P.C.;Erdogan, F.
  21. 도로교표준시방서-설계/시공 및 유지관리편- 건설교통부