Prediction of the rotation capacity of aluminium alloy beams

In this paper the theoretical steps of a semi-empirical method for evaluating the rotation capacity of aluminium alloy members subjected to non-uniform bending are outlined. The approach is represented by the extension to aluminium alloy members of the semi-empirical methods proposed for evaluating the rotation capacity of steel members. The moment-curvature relationship of aluminium alloy members can be conveniently represented by means of a Ramberg-Osgood type relation. This allows, with reference to the classical three-point bending test, the derivation in closed form of the curvature diagram. Furthermore, a closed-form integration of the curvature diagram can be performed, providing a relation for evaluating the rotation corresponding to the occurrence of local buckling. The rotation capacity is then computed. The final ring of this link is represented by the experimental evaluation of the non-dimensional stress corresponding to the attainment of the local buckling. The testing needs for this evaluation are outlined, and both the preliminary test results and the planned activity are presented. Copyright (C) 1996 Elsevier Science Ltd.