Analytical Solution of Two-Layer Beam Taking into Account Non Linear Interlayer Slip

This paper presents a fully-developed nonlinear analytical (exact) model for analyzing composite beams under transverse bending load. The model reproduces the elements responsible for the relative slip between the layers (shear connectors and interface) with an elasto-plastic strain-softening interlayer. Further than the slip, the model predicts stresses due to a given load and ultimate load for debonding, of bi-layered composite beam. All the details on the mathematical development are presented. This paper advances the state of the art, since the last development available in literature is an analytical (non-exact) linear model. A number of parametric studies are conducted to evaluate the influence of various geometrical and material parameters, which main results are presented together with the interpretation, e.g., the dependence of load-carrying capacity, stresses, and deflection, on local nonlinear load-slip relationship. The research proves as well that the shear connection lower and upper bounds (respectively, totally flexible and infinite rigid shear connectors) do not imply any lower and upper bound for the response