Estimation of the parameters of the discrete model of a steel–concrete composite beam

This paper presents estimations of mathematical modelsʹ parameters regarding steel–concrete composite beamsʹ natural vibrations. The model was created using Rigid Finite Element (RFE) Method. Parametersʹ estimation was done based on the results of experimental research, conducted on actual composite beams. Estimated parameters include: shearing and axial stiffness of connecting elements, and substitute longitudinal modulus of elasticity of the reinforced concrete slab, which takes into account longitudinal reinforcement. Employing the appropriate criteria during the process of estimation of the parameters of the steel–concrete composite beam models has a great impact on getting precise results. The estimation criteria were selected in order to achieve consistency of the natural vibration frequencies, along with vibration modes, measured during experimental and calculated based on the mathematical model. The models and all the calculations were made using the MATLAB programming environment.