Papers by Keyword: Ultimate Moment

Abstract: Top-and-seat angle connection is a type of semi-rigid connection, usually used in steel frame. The initial stiffness of top-and-seat angle connection is an important index for steel frame design. The article studied the initial stiffness of the connection considering the influence of column flange. The deformation and mechanical characteristics of top-and-seat angle connection were analyzed using ANSYS. According to the results of FEM analysis, theoretical models of the connection and the initial stiffness formula of connection were proposed. For verifying the correction of the formula, 8 FEM models were built and initial stiffnesses were calculated correspondingly. The formula proposed by the article agreed well with the results of the FEM analysis. And it proves that, the initial stiffness formula of top-and-seat angle connection proposed herein can be used in the design.

Abstract: Top-and-seat angle connection is a type of semi-rigid connection, usually used in steel frame. The stress distribution and the formation of plastic hinge of connection were analyzed using ANSYS. According to the results of FEM analysis, theoretical model of the top angle was proposed. And then, the ultimate moment formula of connection was proposed based on the Mises criterion. For verifying the correction of ultimate moment formula, 13 FEM models were built and ultimate moments were calculated. The formula proposed by the article agreed well with the results of the FEM analysis. And it proves that, the ultimate moment formula of top-and-seat angle semi-rigid connection can be used in the design.

Abstract: Based on appropriate numerical constitutive model of lightweight aggregate concrete filled steel tubes (LCFST), layered method was adopted to predict the complete moment-curvature curves of LCFST composite section subjected to pure bending. A FORTRAN program for the moment-curvature curves was developed. Applying the layered method, the influences of the significant parameters, such as steel ratio, yield strength of steel and strength of lightweight aggregate concrete on the moment-curvature curves of the composite section subjected to pure bending were discussed. The practical composite flexural stiffness, ultimate moment and practical moment- curvature relationship of LCFST composite section were presented. The predicted results of both layered method and practical moment-curvature relationships of LCFST composite section are in good agreement with the test results from reference. Compared with the layered method, practical calculate method could remove the step of composite section layered and improve the calculation speed while achieving similar results.