Mechanical Property Investigation Of The Welded-bolted T-stub Connection Between Square Tubular Column And I-shaped Steel Beam

T-stub connections as a standalone configuration have been widely studied by domestic and overseas scholars over the past years.The emphasis in most of research on this subject was mostly placed on the assessment of connection resistance and stiffness properties.Meantime numerous experimental tests and simulation about T-stub connections was investigated by numerous domestic and overseas scholar.These study were restricted to fully welded connections and fully bolted connections.Fully welded connections have two drawbacks:one is related to the connection geometry,which promotes large strain demands in critical areas;another one is related to the structural conception for modern steel moment frames which demands large forces exacerbate the strain concentration and localization problems according to "weak beam-strong column"mechanism.While the drawbacks related to connection geometry can be addressed through the use of tougher weld materials and better convection detailing,those related to structural conception remain.The numerous failures of fully welded moment connections during 1994 Northbridge and 1995 Kobe earthquakes have shown the inherent drawbacks of fully welded connections.Fully bolted connection is troublesome is construction process.In this paper,a new type of connection:welded-bolted T-stub connection between square tubular column and I-shaped steel beam was analyzed and studied to this problem.Full-scale connections were fabricated to make the experiment under monotonic and reciprocal horizontal loading firstly.ABAQUS 6.10 to be the complement of the experiment.The finite element analysis results were verified by the experimental results.Moment-rotation curve.failure modes,initial stiffness,yield rotation,yield moment,ultimate rotation,ultimate moment,bearing capacity reserve coefficient and ductility coefficient were studied based on this.Then the theory bearing capacity of the joint under several kinds of possible failure mode is calculated.Then theory bearing capacity is compared with the test results.Then skeleton curve,ductility coefficient,capability of energy consumption,stiffness deterioration law and shear-force deformation in core areas were analyzed to evaluate this joint.Finally through the combination of test results and FEA calculation results,it gave the reasonable proposals for the welded-bolted T-stub connection between square tubular column and I-shaped steel beam’s engineering practices.