Civil Engineering Reference
In-Depth Information
vapour pressure gradient and depends on the material's permeability coefficient.
We assume that no air transfer occurs. The model is mainly based on one
developed for fibrous material (Karamanos et al.
2008
).
5.3 Mechanics Models
Besides heat and mass transfer, many attempts have made for modelling
mechanical properties of fibrous materials and their composites. Specifically, (Rao
et al. 2012) extended the micromechanical models in the literature to conduct
micro- and macro-analysis of sisal fibre composites hollow core sandwich panels
and to evaluate the feasibility of using short sisal fibres as reinforcements in the
composites. The stress relaxation behaviour of the composites was examined
experimentally. A steady-state finite element analysis in the linear range was per-
formed in ANSYS environment to examine flexural properties of the panels, and the
shear strength of the hollow cores (Rao et al.
2012
). For fibrous materials, there is a
strong need of micromechanical models because the global nonlinear material
response to loading is defined by the microscopic constituents (Syerko et al.
2012
).
The micromechanical models predict elastic modulus which generally lump the
composite's properties together into constitutive relationship using different
parameters, see also Halpin and Kardos (
1976
) and Cox (
1952
) for the models.
6 Applications
The building and construction industry constitutes one of the largest sectors to
employ fibrous materials in a wide range of products, including light structural
walls, insulation materials, wall and floor coverings, geotextiles and thatch roofing.
We don't distinguish fibrous materials and vegetable fibrous materials here
because their applications are very similar, if not same. on, etc. The purpose of
insulation is to provide a thermal barrier to minimize heat flow through the
components of the buildings.
6.1 Thermal Insulators
Fibrous materials have been extensively used as thermal insulators with a variety
of applications ranging from interior or exterior walls, roofs, foundations, cavity
walls, unheated garages, band joists, storm windows, seal around all windows,
doors and heating system and hot and cold water services. Insulating the attic is a
very important measure as the greatest heat loss occurs through the roof which can
be verified by noting the length of time required for snow on the roof to melt.
