Extended End-plate Bolted Connections Performance Study Of Steel Frame Structure

Beam-to-column connection of steel structure is one of important matter in steel design and research, the reliability and validity of connection have important effect on whole performance of steel structure. Rational connection pattern can improve whole performance of structure greatly and obtain economy and reliability. End-plate bolted connection is the connection pattern that one end of beam welded to end-plate which connected to the flange of column by high strength bolt. If the end-plate extend to the range of height of beam, then, named extended end-plate bolted connection. This connection pattern arouse comprehensive recognition from domestic and overseas scholar because its such advantage: high quality weld bead, relative less material spending, good seismic ductility behavior, relative strong connection rigidity, construction facility and so on, so it become on of pop research problem. The paper, by means of test study and finite element analysis, investigates the behavior of extended end-plate bolted connections which is one of typical semi-rigid connections, under moment-rotation curves, forced performance of connection, connection flexibility effect on whole performance of steel frame. The main scopes of this paper includes:1, Extended end-plate bolted connections and weld connections are tested, bearing capacity, destroy phenomena of test are investigated, by means of finite element, bolt and end-plate performance in every load phase are analyzed.2, All kinds of M-θ curve pattern and the relationship of M -θ which obtain from the result of test are compared in order to find one connection pattern which can describe connection character of extended end-plate bolted connections properly, the pattern is four parameter exponent function. Every parameter of the pattern are explained and deduced in the paper, then, the expression of the pattern are improved and simplified. By means of finite element program, thickness of end-plate and stiffen of column flange affect to connection performance are analyzed.3, Because all kind of connections are semi-rigid connections strictly, so, the paper regard weld connection as strong semi-rigid connections and compare result of test with power model in relationship of M-9, then , the power model introduced to calculate the connection flexible effect on weld connection. At the same time, the initial rigidity of extended end-plate bolted connections which regarded typical semi-rigid connections and the initial rigidity of weld connections which regarded approximate rigid connections are compared in the paper.4, Some advice of connection construction and design in engineering are proposed in the paper...