Model for Moisture-Content Evolution in Porous Building Elements with Hygro-Thermal Bridges and Air-Voids

Addressing the effects of moisture movement and residual moisture-con tents is becoming a recognized part of performance-based design of buildings. However, the multi-directional moisture-movement and subsequent moisture-content evolution in most common building elements with hygro-thermal bridges, without or with air-voids, has yet not been investigated. An integral presentation was utilized to establish the coupled heat and mass transfer field equations for these cases, and for their reduction to a discrete set of alge braic equations. An interactive converging numerical process solves the implicit set of alge braic non-linear equations. Results address some examples for verification of the computational procedure, and a symmetric drying process of an autoclaved-aerated- concrete block-wall with cementitious-mortar joints and renderings, with and without air- voids.