Studies from University of Brescia in the Area of Mechanical Science Reported (Accurate modelling of the linear elastic flexure of composite beams warped by midlayer slip, with emphasis on concrete-timber systems)
By a News Reporter-Staff News Editor at Journal of Technology -- A new study on Mechanical Science is now available. According to news reporting originating in Brescia, Italy, by VerticalNews journalists, research stated, "We focus on the modelling of the linear elastic flexure of composite beams in which the external layers are connected by a midlayer allowing a conspicuous slip between the external layers. In particular, we consider the case of concrete-timber systems in which the midlayer consists of steel shear connectors passing through a wooden plank."
The news reporters obtained a quote from the research from the University of Brescia, "To model these structures, we extend the Newmark theory, originally developed for connection of negligible thickness. Also, we apply Jourawski's technique to the Newmark model to obtain accurate analytic predictions of the shear stress. We provide analytic solutions for the cases of simply supported, cantilever, and propped-cantilever beams, all subject to uniform load, and we compare the results with those obtained from both accurate plane stress Finite Element simulations and the First-Order Shear Deformation (FOSD) theory. For the latter we provide the explicit expression of the shearing rigidity based on a classical energy criterion. We show the inability of the FOSD modelling to accurately predict the deflection and explain the unexpected too large compliance characterising the FOSD estimate. Instead, the Newmark model turns out to be highly accurate for sufficiently slender beams, even in terms of shear stress if the 'Jourawski-like' post-processing proposed here is used. We also consider a further extension of Newmark's theory to accurately model not-too-slender composite beams. In such an extension, henceforth called the Newmark-Timoshenko model, the wooden element is allowed to follow a Timoshenko kinematics, richer than the Euler-Bernoulli kinematics assigned to both the external layers in the Newmark model."
According to the news reporters, the research concluded: "The results of the novel Newmark-Timoshenko model are numerically obtained by the Rayleigh-Ritz method in which the analytic solution of Newmark's model is used to construct optimal approximating functions of the field entering the Total Potential Energy functional."
For more information on this research see: Accurate modelling of the linear elastic flexure of composite beams warped by midlayer slip, with emphasis on concrete-timber systems. International Journal of Mechanical Sciences, 2014;87():268-280. International Journal of Mechanical Sciences can be contacted at: Pergamon-Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, England. (Elsevier - www.elsevier.com; International Journal of Mechanical Sciences - www.elsevier.com/wps/product/cws_home/206)
Our news correspondents report that additional information may be obtained by contacting L. Bardella, University of Brescia, DICATAM, I-25123 Brescia, Italy. Additional authors for this research include L. Paterlini and A. Leronni.
Keywords for this news article include: Italy, Europe, Brescia, Mechanical Science
Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC