Total performance in terms of designed life-span durability requires the integration of various performances that deal with hygrothermal transport, structural loading, and chemical and biological activities. To date, limited work is available that encompasses this spectrum of multidisciplinary activity. This paper presents a new durability model as the first step toward the development of an analytical tool to assist in the design attributes/considerations of hygrothermoelasto-plasticity of building wall assemblies. The development of an uncoupled quasi-static hygrothermoelasticity model for two-dimensional composite building envelope systems is discussed.

The boundary element method, using boundary integral equations for two-dimensional elastic displacements and stresses, is briefly presented. Domain integrals related to hygrothermal body forces were converted to equivalent boundary integrals using the dual reciprocity technique. Together with other innovative techniques, such as analytical evaluations of all the boundary integrals, makes this procedure powerful, robust, and easy to extend to fully nonlinear hygrothermoelasto-plastic.

To demonstrate the capability of this model for durability analysis, an application case is presented for a building wall assembly. An English bond masonry wall system, exposed to actual weather, heat, air, and moisture transport boundary conditions for the city of Ottawa, is analyzed. Hygrothermal-elastic numerical results show that high magnitudes of shearing stress are concentrated in the mortar layer, which is consistent with empirical knowledge on the deterioration of masonry walls. In addition, the direct coupling effects of weather and the hygrothermal response of the wall system on the structural behavior is clearly identified during periods of wind-driven rain.

• HAM hygrothermal simulation : hygrothermoelasticity

1. A North American research approach to moisture design by modeling
2. Advanced hygrothermal modeling of building materials using MOISTURE-EXPERT 1.0
3. Advanced hygrothermal models and design models
4. An educational hygrothermal model: WUFI-ORNL/IBP
5. Applied moisture engineering
6. Barrier EIFS clad walls: Results from a moisture engineering study
7. Building enclosure hygrothermal performance study phase I
8. Drying capabilities of wood frame walls with wood siding
9. EIFS hygrothermal performance due to initial construction moisture as a function of air leakage, interior cavity insulation, and climate conditions
10. Hygrothermal system-performance of a whole building
11. Importance of moisture control in building performance
12. Influence of material properties on the hygrothermal performance of a high-rise residential wall
13. Integrated approaches for moisture analysis
14. Integrated hygrothermal performance of building envelopes and systems
15. Measurements and two-dimensional computer simulations of the hygrothermal performance of a wood frame wall
16. Moisture transport in building envelopes using an approximate factorization solution method
17. Position paper on material characterization and HAM model benchmarking
18. Simulation of indoor temperature and humidity conditions including hygrothermal interactions with the building envelope
19. Wind-driven rain distributions on two buildings
20. WUFI-ORNL/IBP - A North American Hygrothermal Mode