Issue 38

P. Lonetti et alii, Frattura ed Integrità Strutturale, 38 (2016) 359-376; DOI: 10.3221/IGF-ESIS.38.46 359 A numerical study on the structural integrity of self-anchored cable-stayed suspension bridges Paolo Lonetti, Arturo Pascuzzo Department of Civil Engineering, University of Calabria, Via P. Bucci, Cubo39-B, 87030, Rende, Cosenza, Italy paolo.lonetti@unical.it; 0000-0003-0678-6860 arturo.pascuzzo@unical.it ; 0000-0003-3879-6764 A BSTRACT . A generalized numerical model for predicting the structural integrity of self-anchored cable-stayed suspension bridges considering both geometric and material nonlinearities is proposed. The bridge is modeled by means of a 3D finite element approach based on a refined displacement-type finite element approximation, in which geometrical nonlinearities are assumed in all components of the structure. Moreover, nonlinearities produced by inelastic material and second order effects in the displacements are considered for girder and pylon elements, which combine gradual yielding theory with CRC tangent modulus concept. In addition, for the elements of the suspension system, i.e. stays, hangers and main cable, a finite plasticity theory is adopted to fully evaluate both geometric and material nonlinearities. In this framework, the influence of geometric and material nonlinearities on the collapse bridge behavior is investigated, by means of a comparative study, which identifies the effects produced on the ultimate bridge behavior of several sources of bridge nonlinearities involved in the bridge components. Results are developed with the purpose to evaluate numerically the influence of the material and geometric characteristics of self-anchored cable-stayed suspension bridges with respect also to conventional bridge based on cable- stayed or suspension schemes. K EYWORDS . Self-anchored cable-stayed suspension bridges; Structural integrity; Nonlinear, Plasticity; Ultimate behavior; Finite element method. Citation: Lonetti, P., Pascuzzo, A., A numerical study on the structural integrity of self-anchored cable-stayed suspension bridges, Frattura ed Integrità Strutturale, 38 (2016) 358-376. Received: 01.08.2016 Accepted: 05.09.2016 Published: 01.10.2016 Copyright: © 2016 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. I NTRODUCTION able supported bridges are frequently employed to overcome long spans, because of their aesthetic, structural and economic properties, if compared to conventional and standard bridge schemes [1, 2]. However, as the span length increases more advanced analyses are needed to improve safety and reliability of these structures, reproducing accurately all sources of nonlinearities involved in the bridge components. Such task becomes much C