Transporte de calor, umidade e sal em meios porosos

Abstract

Concrete structures can suffer from different types of damage, which can considerably shorten their life. One of the responsible for this process is the transport of salts into the pores of the concrete. Besides accelerating the corrosion process in the steel frame, these salts can concentrate at some points (nucleation), causing cracks in the structure, consequently decreasing the resistance. In this context, the objective of this work is analyze numerically how this transport takes place inside the porous structures, simultaneously considering the transport of heat, moisture and salt in the porous medium. The discretization of the governing equations was performed using the finite volume method, and the algebraic equations system was solved by means of MultiTriDiagonal Matrix Algorithm (MTDMA), which allows the simultaneous resolution of the governing equations. For the verification of the model, several simulations considering different boundary conditions were performed and compared with the isothermal model presented by Zanden, Taher and Arends (2015), presenting satisfactory resemblance between the results. From the results it is possible to observe the influence of moisture transport on the salt displacement inside the porous medium, both in the drying process and in the inhibition process. Thus, this work was promising in the analysis of the salt transport in the porous medium, being able to provide important information for the prevention of the corrosion and deterioration processes of the concrete.