Properties of gypsum bonded solid bricks manufactured with recovered wood and rubber

Elias Voulgaridis1, Stergios Adamopoulos2, Costas Passialis1, Dafni Foti1, Eleni Voulgaridou1.

1Aristotle University of Thessaloniki, Department of Forestry and Natural Environment, Laboratory of Forest Utilization, 541 24 Thessaloniki, Greece

2Technological Educational Institute of Thessaly, 431 00 Karditsa, Greece


Abstract
Utilization of recovered wood fromparticleboard production residues and rubber from waste tires in the manufacture of solid bricks was investigated, using gypsum as bonding media. The manufacturing parameters were: small and large rubber and wood particles, different gypsum/wood/rubber ratios for each fraction (small, large), and different gypsum/water ratios. Cylindrical samples, produced by pouring the mixtures into cylindrical molds, were used for testing compressive strength, thermal conductivity and sound absorption according to standard methods.Compressive strength of all gypsum bonded wood and rubber samples was much lower than the controls, e.g. pure gypsum samples. It was found that the wood samplesand the larger fractions (both rubber and wood) were superior in strength than the rubber samples and small fractions, respectively. A maximum proportion25% of wood or rubber as well the use of reclaimed fibrous materials in the manufacture of samples would probably ensure an acceptable compressive strength. No differences were found among the wood/rubber typesfor thermal conductivity, while particle size and proportion of the materials had no effect. Samples with small wood and rubber particles at the lower proportion (25%) were similar in their sound absorption behaviour.

*The research has been funded by the European project LIFE09 ENV/ES/000454 WoodRub “Utilisation of recovered wood and rubber for alternative composite products” (2010-2013)