Elastic theory of layered beams

Abstract

The classical theory of layered beams is presented in details. The theory has been presented originally in 1940’s to the design of composed wooden structures. Discussion of the basic assumptions is given in order to estimate the validity of the theory in different cases. Different formulations of the boundary conditions are presented. Some analytic solutions are given. These solutions are used in numerical examples. Summaries of recently presented cases of cross-laminated timber (CLT) beams and steel-timber composite beams are given including validation of the theory against experimental researches done by others. It is seen that the theory seems to be useful in estimation of the behaviour of these rather novel innovative structures. So far the theory has been used in the standards of sandwich and steel structures, but it seems to be suitable for possible future standards of CLT and steel-timber composite structures, as the theory was originally developed for wooden structures.