Lightweight wood chipping concrete durability

The recycling of wood chippings, an industrial waste product, has a potential use in the production of a lightweight mortar. In developing countries, the low cost and the proximity of supply makes this material a good candidate for local building applications. This study aims at examining the durability of a wood fibre lightweight concrete. Samples have been stored in humid and dry environments; compressive and flexural strength were measured and the microstructure examined using SEM. The material properties are improved when wood chippings are saturated with a sodium silicate solution; this is due to the improved bond between chippings and cement paste, resulting from the formation of CSH I and ettringite. The results are encouraging and indicate the feasibility of producing a lightweight concrete that conforms to the RILEM recommendations.