A NUMERICAL STUDY ON NETWORK ARCH BRIDGES SUBJECTED TO CABLE LOSS

A numerical study is proposed to investigate the structural behavior of network arch bridges subjected to the cable loss accidental event. The main aim of the paper is to analyze the effects produced by potential cable loss scenarios on the main stress and kinematic design variables of the structure. To this end, a parametric study in terms of the main structural and geometric parameters is developed with the purpose to identify the key factors that contribute to reduce hazards produced by the cable loss event. The structural analyses are performed by using a refined FE nonlinear geometric formulation, in which the influence of large displacements and local vibrations of cable elements are taken into account. The loss of the cable is reproduced by means of a proper damage law, developed in the framework of Continuum Damage Mechanics theory. Cable loss analyses are performed by means of both nonlinear dynamic analyses and simplified methodologies proposed by existing codes on cable supported bridges. In this framework, the applicability of such simplified methodologies in the case of the network arch bridges are discussed.