Influence of microfine-contaminated sand from Mandulog River system in Iligan City, Philippines on the performance of concrete

Abstract

The presence of microfines in the concrete matrix is a concern, as it affects the fresh and hardened properties of concrete. As such, aggregates quarried from rivers with considerable amounts of microfines need to undergo a pretreatment process to remove the microfines, which could be a costly endeavor. This is the case for aggregates quarried from Mandulog River in Iligan City, Philippines, where microfines are present. This paper, therefore, set out to find the influence of the microfines on the performance of concrete by determining its effect on the slump, the water demand, and compressive strength of concrete with microfines from 1 to 6% at 1% increment of the weight of fine aggregates. Experimental results showed that microfines in concrete could affect the slump and water demand for concrete minimally. In particular, the compressive strength at the 28^th-day curing period was not significantly affected; thus, it can be concluded that microfines of up to 6% of the weight of fine aggregates can be tolerated for concretes produced using aggregates from the Mandulog River system.