الفهرس 
Water Soaking for WoodOnly 14 pages are availabe for public view
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Abstract
Composite panels are a very common and perhaps the most popular use of composites.
Wood-based composites are used for a number of nonstructural and structural
applications in product lines ranging from panels for interior covering purposes to panels
for exterior uses and in furniture and support structures in buildings.
Medium density fiberboard (MDF) as a dry-formed panel product manufactured from
lignocelluloses fibers combined with a synthetic resin, was used to improve their
performance and serviceability. Therefore, it needs to be enhanced. In this thesis, MDF
used as core in sandwich panel with laminated composite from fiberglass with epoxy
resins as facing sheet on two faces. Some the natural, mechanical and fracture properties
of MDF was studied and compare with sandwiched MDF. Water soaking properties
(thickness, length and weight) were measured before and immediately after soaking and
microbial bioassay test (decay resistance test) for MDF and sandwiched MDF. The
strength of MDF and sandwich panel, which is the ultimate strength under different
modes of loading, such as tension and bending was measured, also modulus of elasticity
and modulus of rupture. Fracture toughness is one of the fracture properties that
determined by using the Compact Tension (CT) test and center crack tension test. The
stress intensity factor (KIC) of MDF panel and sandwiched MDF was measured and a
comparison between the results. The interlaminar fracture toughness of sandwich panel
was measured using double cantilever beam (DCB), those specimens with (25mm) of initial delamination. The bearing strength was determined by bolted joint test using
double lap joints. The ABAQUS software package, to study mechanical properties of
sandwiched MDF (tension and bending) by using finite element method (FEM) and the
results comparison with experimental results.