Mechanical strength and compactness of bio self-compacting sand concrete containing granite industrial waste as fine aggregate
Moussa Hadjadj, Mohamed Guendouz, Djamila Boukhelkhal
Abstract
The sector of civil engineering has shifted towards the direction of sustainable development, with a focus on environmental protection as an important objective. This strategy is implemented by recycling and reusing polluted industrial by-products and waste. The manufacturing process of granite products generates huge quantities of granite waste (GW) worldwide, which causes environmental pollution when dumped. Self-compacting sand concrete (SCSC) is a novel, highly fluid, and durable concrete widely used as a construction material. In this work, the effect of using recycled waste granite (GW) and seashell powder (SSP) on the mechanical strength and compactness of eco-self-compacting sand concrete (SCSC) was studied. For this purpose, SSP has been used to substitute cement at levels of 5, 10, and 15% by weight, and GW replaced the natural sand at levels of 0, 10, 20, 30, and 40% by volume. The fresh properties of SCSC mixtures are evaluated by the mini-slump flow diameter. The compressive and flexural strengths and compactness of hardened SCSC were assessed. A SEM analysis was also used to examine the microstructure development of the hardened SCSC mixtures. The results indicate that using SSP for GW- based SCSC gives acceptable flowability with a low dosage of superplasticizer (SP). Moreover, an enhancement in compressive and flexural strengths and compactness of the SCSC mixtures was found by adding up to 40% GW combined with up to 15% SSP. 10SSP+40GW mix showed the highest mechanical strengths and compactness, with a denser microstructure after 90 days with an improvement of 30.61% and 35.82% in compressive and flexural strength, respectively, compared to control mixtures.