On the post-elastic behavior of LRPH connections

Abstract

The paper concerns the study of the post-elastic behavior of a recently proposed innovative device, named Limited Resistance Rigid Perfectly Plastic Hinge (LRPH). In particular, LRPH is a steel device of finite length realizing a moment connection between beam elements of a steel frame; it is designed in order to possess two main and independent requirements: its bending moment resistance must be suitably lower than the one of the connected beam element and its overall bending stiffness must be equal to that of the connected beam element characterized by the same length. In order to make the proposed device reliable, LRPH must be capable of realizing a full plastic hinge for the assigned bending moment limit value. This feature can be ensured by imposing some appropriate lower bound constraints on the geometry of the relevant device. The correct definition of these bounds is achieved by means of a preliminary FEM analysis of the device. The present paper is devoted to the definition of these bounds and to the consequent formulation of a wider optimization problem of the LRPH device.