Performance Of Partial-Depth End-Plates Beam-To-Column Composite Joints Of Steel Frames Under Hogging Moment

As the key part of the beam-column connection in the structural steel frame, the connected capacities influence the integral responses of the whole frame on loading. Some researches showed that the strength and stiffness of the connection could increase obviously if the effect of the slab were considered. Beam-to-column composite joints with partial-depth end-plates, which can be regarded as a special example, have a wider developed space because of their easier configuration and convenient construction.In this paper, the static behavior of the'I'shaped composite joint with partial-depth end-plates under the vertical load was studied. The main contests are listed as follows:(1) The simplified model of composite joint with partial-depth end-plates, which will be used in the ANSYS FEM software, was built up. By the comparison between calculated results and experimental results, the veracity and precision of such FEM model were proved. Such checkout provided the assurance for the correctness of the following research method and parameter analysis.(2) By the analysis of different parameters, the influences, which include slab reinforcement ratio, reinforcement yield stress, slab concrete grade, steel grade, steel beam height, end-plate thickness and the end-plate height, were obtained. The classification of different types of connections was also carried out according to the corresponding notes in Eurocode 3 in addition.(3) By analyzing the characteristics of the connections, the calculating methods of initial stiffness and elastic moment resistance of connections in Eurocode 4 were modified or simplified. In addition, the calculated results were compared with the FEM analysis results.(4) In order to analyze the working capacities of the connections, some parameters in the design methods of Eurocode 3 were modified. The mathematical model of the relations between bending moment and the angle of rotation were also provided and the calculated results were compared with the FEM analysis results.