Studying the Effect of Using Local Porous Volcanic Aggregate on the Compressive Strength of Concrete

Abstract

The sustainable development of the construction sector in arid regions requires the optimization of local natural resources to minimize environmental impact and transportation costs. This study investigates the feasibility and performance of replacing conventional limestone coarse aggregate (CCA) with volcanic aggregate (Basalt rocks) sourced from the Haruj volcanic field in central Libya. An experimental program was conducted using five concrete mixtures with volumetric VA replacement levels of 0%, 25%, 50%, 75%, and 100%. The study encompassed a detailed characterization of aggregate properties, followed by an evaluation of fresh concrete behaviour (workability, density) and hardened properties (compressive strength at 7, 28, and 90 days, water absorption, and permeability). Results indicate that Haruj VA is a dense, high-strength material with a Los Angeles Abrasion value of 20.48%, comparable to high-quality conventional aggregates. The angular shape and better grain interpenetration also contributed to improving the mechanical performance of the hardened matrix. The 100% VA mixture achieved a 28-day compressive strength of 37.69 MPa, representing an increase of approximately 70% over the reference mix (22.10 MPa). Furthermore, durability was markedly improved, evidenced by a 55% reduction in water penetration depth. This study concludes that Haruj volcanic aggregates are a superior alternative to conventional sedimentary aggregates for producing high-strength, low-permeability structural concrete.