Particle Sizes and Wood/Cement Ratio Effect on the Production of Vibro-compacted Composites

The aim of this study was to evaluate the influence of particle size and the wood/cement ratio on the physical and mechanical properties of vibro-compacted wood-cement composites. The effects of three different particle sizes (diameter between 1.4-2.36 mm; 2.36-4 mm; and 4-9.56 mm) and wood:cement ratios of 1:2.75, 1:2 and 1:1.5 on wood-cement composites produced with the Amazonia species Swartzia recurva Poepp. and Portland cement type II-Z were analyzed. All evaluated properties were influenced by the particle size used in the mixture; however, the wood:cement ratio only affected the final density of the composite, internal bond and water absorption properties. Composites produced with particles that pass through a 2.36 mm screen but were retained with a 1.4 mm screen showed average values of modulus of rupture and higher modulus of elasticity than composites produced with bigger particles. The use of a 1:2.75 wood:cement ratio resulted in composites with higher density and dimensional stability than composites produced with a lower amount of cement.