OPEN ACCESS
The construction sector has been adopting sustainability strategies to reduce the negative impacts of this industry. One of the most relevant strategies over the last years has been the incorporation of waste and natural materials. There has also been a more systematic demand for high-performance products with improved technical properties. Due to its durability and highly functional properties after harden- ing, concrete is one of the most commonly used building materials. Since there is a great volume of concrete being produced every year, studies are being developed to improve its sustainability through the incorporation of waste materials to substitute aggregates. In this context, the use of natural fibres and agricultural by-products such as rice husk offers important environmental advantages and it can be seen as an opportunity to recover a by-product with a high environmental disposable impact. At the same time, by partially replacing conventional aggregates with rice husk, the density of concrete can be lowered, contributing to greater economy in handling and transportation costs, improved thermal and acoustic performance and to an overall more sustainable material. This research aims to assess the potential of cement-based composite materials with rice husk through experimental characterisation tests and to address the main challenges regarding the incorporation of vegetable fibres in cement- based mixtures. The preliminary results obtained suggest that these cement-based composites will be adequate for thermal and acoustic performance of buildings, while contributing to generate waste recovery opportunities for the construction industry.
Rice husk, Vegetable fibres, Cement composites, Sustainable materials
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