ABSTRACT
Wood fibers have been used for many years as an additive in the conventional asbestos cement industry; some of the asbestos cement replacement products also utilize wood fibers. In these cases, wood fibers contributes mainly processing benefits rather than reinforcement. Recent studies have shown that the reinforcement ability of wood fibers is quite good relative to other potential asbestos replacements (Coutts 1988; Vinson et al. 1989; CSIRO 1981). There are, however, concerns regarding the moisture resistance of wood fiber-cement composites. Considerable differences in flexural strength and fracture toughness values are observed when the specimens are tested at different moisture contents (Coutts 1984). High moisture contents tend to damage the fiber-to-matrix bond strength, leading to changes in failure mechanism which can describe the trends observed in moisture effects on flexural performance of wood-cement composites (Morissey et al. 1985).
