A penalty model for the analysis of composite curved beams

A one-dimensional mechanical model of curved laminated beams is presented. The different laminae forming the laminate are modeled as Timoshenko beams perfectly bonded at the interfaces. Such elements are allowed to rotate differently from one to the other, simulating the warping of the overall cross-section. The elastic problem of the beam is formulated in variational form, through the principle of stationary potential energy. The originality of the present approach, as compared to previous studies of the authors on the same subject, consists of a penalty approach to the adhesion constraints between adjacent laminae. Such a technique produces a direct approximation of radial and tangential interlaminar stresses. Numerical results are obtained through a finite-element approximation, leading to the prediction of the interlaminar stresses in several examples of straight and curved laminated beams. Comparisons are established with similar results obtained by other authors through different approaches