Sustainable integration of lightweight expanded clay aggregate (LECA) in concrete for environmental resilience: A performance evaluation

Abstract

Promoting sustainability and green construction has gained more attention in society. This research has been focused on promoting sustainability and green construction by using lightweight expanded clay aggregate (LECA) as an alternative to natural coarse aggregates in concrete mixes. This approach has not only been promoted lightweight properties but also prioritized sustainability in construction, thereby minimizing the carbon footprint in the industry. The study has been focused on analyzing the physical properties of LECA aggregate and examined its porous structure and elemental characterization of LECA through scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. Pre-soaking of LECA aggregate has resulted in enhanced workability, with an increase in slump and water absorption characteristics. In addition, the mechanical properties of LECA-infused concrete at 0, 25, 50, 75, and 100% with a grade of M25 have been analyzed, and a decrease in compressive, split tensile, and flexural strengths has been observed with increasing LECA content due to its high porosity and water absorption, which have impacted the density and strength parameters. The findings have shown that the addition of presoaked LECA has increased water absorption, sorptivity coefficient, chloride ion penetration, loss of mass, strength loss, and deterioration effects on acid and sulphate resistance. Furthermore, microstructural analysis has been carried out to ensure the microstructure and presence of essential chemical elements in LECA-infused concrete.