Current standards require that welded column splice connections in Special or Intermediate Resisting Frames (IMRFs or SMRFs) feature Complete Joint Penetration (CJP) groove welds to minimize stress concentrations due to the flaw produced by Partial Joint Penetration (PJP) welds. In contrast to PJP welds, CJP welds are often costly, requiring additional material, inspection and back-gouging to ensure complete penetration. However, unlike Welded Beam Column connections which fractured in the 1994 Northridge Earthquake, column splices have modest deformation demands, implying that perhaps with the use of modern, toughness-rated weld filler materials, PJP welded splices may offer acceptable performance. Motivated by these observa-tions a study featuring five full-scale tests on PJP-welded column splices is presented to examine their feasibility for use in IMRFs or SMRFs in seismic environments. The tests matrix interro-gates a range of parameters including column sizes (consistent with use in 4-20 story buildings) as well as variations in connection details (single and double-beveled, welded and unwelded webs, presence of a weld access hole). The specimens were loaded cyclically in a three-point bend configuration such that the splice is subjected to demands consistent with those anticipated in severe earthquakes; a loading protocol is developed specifically for this purpose based on Nonlinear Time History simulations. All the full-scale specimens exhibited excellent performance, such that the splices exceeded the moment capacity of smaller connected column. The full scale data is complemented by a series of ancillary tests such that the results may be interpreted with respect to measured, rather than specified material properties. A series of Finite Element (FE) fracture mechanics simulations is also presented to assist with the generalization of test results. The FE simulations indicate that for the tested connections, the toughness demands are well below the minimum expected toughness suggesting that details similar to the ones tested in the study may be suitable for general use in the field. A synthesis of the test and simulation data is encouraging from the perspective of adoption of PJP welded splices in IMRFs and SMRFs in seismic regions. Limitations of the research are outlined, along with discussion of future work that may develop further support for the use of PJP welded splices in moment frames.
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