Valorization of glass waste as partial substitution of sand in concrete – Investigation of the physical and mechanical properties for a sustainable construction

Abstract

Over the past few years, the valorization of industrial waste and by-products has become an essential issue due to the increasingly stringent regulations regarding the environmental protection and sustainable development. For the purpose of reducing our dependence on virgin raw materials, it was deemed interesting to consider the recycling and valorization of glass, which has high silica content, to develop new construction materials. Its use as a substitute raw material in the field of construction materials has attracted research attention, particularly the concrete industry adopts a number of methods to achieve this goal. In this context, a purely experimental study was conducted to investigate the physical and mechanical properties of fresh and hardened concrete at different curing times (3, 7 and 28 days) using different dosages of glass sand as a partial substitute for natural sand at 10%, 20%, and 30% and to determine the optimal composition of glass powder as a partial replacement for sand against the compressive strength of concrete. while maintaining a constant water-to-cement (W/C) ratio. An overall quantity of 9.5 kg of crushed waste glass was used with 264 kg of concrete mixes. The workability, density, slump, content air tests and strength properties were analyzed in terms of waste glass content in terms of waste glass content. This substitution results in concrete with favorable workability. Despite the absence of air-entraining agent, the concrete mixtures have air content between 2.3% and 1.9% and the density, is still comparable to the control mixes. The compressive strength of specimens with 20% waste glass content and the flexural strength of specimens with 10% waste glass content represented respectively 96% and 86% than of the control specimen at 28 days. The results proved a pozzolanic strength activity given by waste glass after 28 days for 10% and 20% of replacement of natural sand (0/1 mm). The results obtained indicate that glass can serve as a quality substitute for sand in concrete. These original achievements pave the way for more sustainable and environmentally friendly concrete mixes while addressing the inherent challenges of using glass waste in construction and infrastructure works