Time analysis of composite beams with partial interaction using available modelling techniques: A comparative study

This paper presents a comparison of available numerical structural formulations for the short- and long-term analysis of composite beams with partial shear interaction. The finite difference method, the finite element method, the direct stiffness method and the exact analytical model have been considered, and both the instantaneous analysis and the time analysis based on the age-adjusted effective modulus method (AEMM) have been carried out. For modelling based on the first two of these formulations, a spatial discretisation and a discretisation in the time domain are required, while only the time discretisation needs to be specified for the direct stiffness method. The results obtained using these formulations are compared qualitatively and their accuracy is estimated, adopting the exact analytical model as a benchmark reference with the objective of establishing the minimum spatial discretisations required to keep the error within an acceptable tolerance. These comparisons are carried out for simply supported beams, propped cantilevers and fixed ended beams, from which the qualitative behaviour of these formulations in the modelling of continuous beams can also be deduced.