Vibrations of steel-concrete composite beams

This paper is an experimental analytical investigation on the dynamic behavior of steel-concrete composite beams subject to small vibrations. A one-dimensional model of a composite beam is presented, where the elements connecting the steel beam and the reinforced concrete slab are described by means of a strain energy density function defined throughout the beam axis. The problem of small vibrations of the system is formulated and solved through an analytical procedure where a coupling between longitudinal and transversal motions, due to the presence of the connection, takes place. The analytical model is used with a view to interpreting a series of dynamic tests performed on composite beams whose connections have different linear densities. Experimental results proved consistent with theoretical estimates and allowed the identification of some important physical parameters of the system and the characterization of the connection.