Methodology for the analysis of post-tensioned structures using a constitutive serial-parallel rule of mixtures

CORNEJO, A.; BARBU, L.G.; ESCUDERO, C.; MARTÍNEZ, X.; OLLER, S.; BARBAT, A.H.

COMPOSITE STRUCTURES

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2018

0263-8223

The main purpose of this paper is to develop a reliable method based on a three-dimensional (3D) finite-element (FE) model to simulate the constitutive behaviour of reinforced concrete structures strengthened with post-tensioned tendons taking into account the reduction of the pre-stressing stress due to the steel relaxation. The post-tensioned concrete is modelled as a composite material whose behaviour is described with the serial-parallel rule of mixtures (S/P RoM) [1-3] whereas the stress relaxation of the steel is simulated using a viscoelastic model called Generalized Maxwell. A 3D FE model was used, where the nonlinear material behaviour and geometrical analysis based on incremental?iterative load methods were adopted. Validation by comparison with the analytic solution will be done for the case of a concrete beam with a parabolic pre-tensioned steel tendon embedded and some viscoelastic cases are performed in order to perceive the behaviour of the Generalized Maxwell model. Several examples are shown where the capabilities of the method on large scale structures are exhibited.