Steel and Composite Structures

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Welded plate and T-stub tests and implications on structural behavior of moment frame connections

  • Dong, P. (Center for Welded Structures Research, Battelle Memorial Institute) ;
  • Kilinski, T. (Center for Welded Structures Research, Battelle Memorial Institute)
  • Published : 2002.02.25
⟨ Previous Next ⟩

Abstract

A series of tests on simple-welded plate specimens (SWPS) and T-stub tension specimens simulating some of the joint details in moment frame connections were conducted in this investigation. The effects of weld strength mismatch and weld metal toughness on structural behavior of these specimens were considered under both static and dynamic loading conditions. Finite element analyses were performed by taking into account typical weld residual stress distributions and weld metal strength mismatch conditions to facilitate the interpretation of the test results. The major findings are as follows: (a) Sufficient specimen size requirements are essential in simulating both load transfer and constraint conditions that are relevant to moment frame connections, (b) Weld residual stresses can significantly elevate stress triaxiality in addition to structural constraint effects, both of which can significantly reduce the plastic deformation capacity in moment frame connections, (c) Based on the test results, dynamic loading within a loading rate of 0.02 in/in/sec, as used in this study, premature brittle fractures were not seen, although a significant elevation of the yield strength can be clearly observed. However, brittle fracture features can be clearly identified in T-stub specimens in which severe constraint effects (stress triaxiality) are considered as the primary cause, (d) Based on both the test and FEA results, T-stub specimens provide a reasonable representation of the joint conditions in moment frame connections in simulating both complex load transfer mode and constraint conditions.

Keywords

References

  1. Brust, F.W., et al., NUREG/CR-6098, (1993), "Loading rate effects on strength and fracture toughness of pipe steels used in task 1 of the IPIRG program", Prepared by Battelle for the US NRC.
  2. Brust, F.W., Zhang, J. and Dong, P., (1997a), "Pipe and pressure vessel cracking: the role of weld induced residual stresses and creep damage during repair", Transactions of the 14th International Conference on Structural Mechanics in Reactor Technology (SMiRT 14), Lyon, France, 1, 297-306.
  3. Brust, F.W., Dong, P. and Zhang, J., (1997b), "Crack growth behavior in residual stress fields of a core shroud girth weld", Fracture and Fatigue, H. S. Mehta, Ed., PVP. 350, 391-406.
  4. Dong, P., (2000), "Modeling of weld residual stresses and distortions: computational procedures and applications", Welding Research Council Bulletin, No. 455, September, 1-11.
  5. Dong, P. and Gordon, J. R., (1992), "The effect of weld metal mismatch on the fracture behavior of centercracked panels", 1992 ASME Pressure Vessels & Piping Conference, June 21-25, 1992, New Orleans, Louisiana, PVP 241, Fatigue, Fracture, and Risk, pp. 59-67.
  6. Dong, P., Kilinski, T., Zhang, J. and Brust, F.W., (1999a), "Effects of strength/toughness mismatch on structural and fracture behaviors in weldments", (Sub-Tasks 5.2.1 And 5.2.2), Battelle Final Report to SAC Steel Project.
  7. Dong, P. and Zhang, J, (1999b), "Residual stresses in strength-mismatched welds and implications on fracture behavior," Engineering Fracture Mechanics, 64, 485-505. https://doi.org/10.1016/S0013-7944(99)00088-0
  8. Dong, P., Zhang, J. and Brust, F.W., (2000), "Fracture mechanics analysis of moment frame joints incorporating welding effects", submitted for publications in ASCE Journal Civil Engineering Materials.
  9. Marschall, C.W., et al., 1994, "Effect of dynamic strain aging on the strength and toughness of nuclear ferritic piping at LWR temperatures", NUREG/CR-6226.
  10. Matos, C. and Dodds, R., (2000), "Modeling the effects of residual stresses on defects in welds of steel frame connections", Engineering Structures, 22(9), 1103-1120. https://doi.org/10.1016/S0141-0296(99)00055-3
  11. Rudland, D.L, Brust, F., (1997), "The effect of cyclic loading during ductile tearing on the fracture resistance of nuclear pipe steels", Fatigue and Fracture Mechanics: 27, ASTM STP 1296, R.S. Piascik, J.C. Newman, and N.E. Dowling Eds., American Society of Testing and Materials, 406-426.
  12. SAC 95-08, (1995), Background Report: Metallurgy, Fracture Mechanics, Welding, Moment Conncetions and Frame Systems Behavior, Prepared by the SAC Joint Venture for the Federal Emergency Management Agency, Report No. FEMA-288, Washington, D.C.
  13. Scott, P., Olson, R. and Wilkowski, G., (1994), "The IPIRG- 1 pipe system fracture tests experimental results in fatigue", Flaw Evaluation, and Leak-Before-Break Assessments, ASME PVP 280, 135-151.
  14. Zhang, J., Dong, P. and Brust, F.W., (1998), "Residual stress analysis and fracture assessment of welded joints in moment resistance frames", Proc. Int. Conf. on Advances in Computational Engineering Science, Vol. II: Modeling and Simulation Based Engineering, Atluri, S.N., and ODonoghue, P.E., eds., 1894-1902.
  15. Zhang, J., Dong, P., F.W. Brust, and others, (1999), "Modeling of weld residual stresses in core shroud structures", Nuclear Engineering and Design, 195, 171-187.
  16. Zhang, J. and Dong, (2000), "Residual stresses in welded moment frames and effects on fracture", ASCE J. Struct. Eng., March, No. 3.