Modeling of Viscoelastic Phenomena in Concrete StructuresA. Pomarico , G. Roselli , D. Caltabiano ,
 STMicroelectronics, Lecce, Italy
 STMicroelectronics, Agrate, Italy
A growing demand is recently emerging of sensors to be integrated in the concrete in order to measure some critical parameters, such as humidity and temperature and the internal pressure of the material. For example, by monitoring the pressure in various strategic points of the structure and their evolutions over time it is possible to understand the health of the structure and the needs for maintenance intervention. In this study, an ad-hoc model based on Kelvin chains has been used to model concrete peculiarities and in particular its viscoelasticity characteristics exploiting the equation-based modeling capabilities of COMSOL Multiphysics® software. The generalized Kelvin model consists of an elastic spring to represent the instantaneous stiffness plus n Kelvin-Voigt branches connected in series. The creep function results in a linear combination of exponential terms. The model was compared with viscoelastic creep of concrete obtained from theoretical model, showing a perfect agreement.