Glass foams produced from soda-lime glass waste and rice husk ash applied as partial substitutes for concrete aggregates

Abstract

Concrete is one of the most widely consumed materials in the world. It is composed mainly of natural aggregates - 70–80% of its volume. Extraction of natural aggregates for concrete production harms the environment, and has decreased over the past years. The use of recycled aggregates that can replace natural aggregates in concrete and meet the specifications of structural projects can be an economical and sustainable solution for the construction industry. This study investigated the effects of partial replacement of natural aggregates (pebbles) with glass foam (10–30 %wt), produced with soda-lime glass wastes, rice husk ash and calcium carbonate, on the uniaxial compression strength (3, 7, 28, 56, and 90 days) and consistency (Slump test) of structural concrete. Results show that the larger the size and concentration of the recycled aggregates, the lower the mechanical compressive strength of concrete. Hence, the highest compressive strength at all ages was shown by the material with 4.8mm glass foams and 10% addition - 38MPa after 90 days. Furthermore, partial replacement positively favors the slump of concrete (>90mm), enabling its commercialization and workability for pumping from mixer trucks.