Dynamic analysis of composite steel–concrete structures with deformable connection

Abstract

In this paper a solution to the dynamic problem of reinforced concrete slabs stiffened by steel beams with deformable connection including creep and shrinkage effect is presented. The adopted model takes into account the resulting inplane forces and deformations of the plate as well as the axial forces and deformations of the beam, due to combined response of the system. The analysis consists in isolating the beams from the plate by sections parallel to the lower outer surface of the plate. The forces at the interface producing lateral deflection and inplane deformation to the plate and lateral deflection and axial deformation to the beams are linearly related with the interface slip through the shear connector stiffness. Any distribution of connectors along the interface can be handled. The creep and shrinkage effect relative with the time of the casting and the time of the loading of the plate is taken into account. The method of analysis is based on the capability to establish a flexibility matrix with respect to a set of nodal mass points using the analog equation method (AEM) for the static plate problem. Both free and forced transverse vibrations are considered. Moreover, the influence of the interface slip and the opposed action of creep and shrinkage effect to the behaviour of the stiffened concrete slab is investigated through numerical examples with great practical interest.