Effects on structural light weight aggregate concrete cast using controlled permeable formwork liner

Abstract

The porosity of the concrete surface has the greatest influence on the durability qualities of the concrete. The surface porosity of concrete can be lowered by lowering the water-to-cement ratio. The present study investigates the durability properties of structural light weight concrete using Sintered Fly Ash Lightweight Aggregate (SFLA) combined with Controlled Permeable Formwork (CPF) liners. The Structural Light Weight Concrete (SLWC) possesses a denser Interfacial Transition Zone (ITZ), internal curing effect, and absence of wall effect. By draining excess water and air bubbles near the surface, CPF liners improve the quality of the concrete surface. Various tests were conducted to measure water penetration depth, water absorption, surface resistivity, charges passed, rebound number, pulse velocity, and wear resistance. The experimental results show that the combination of CPF liners and SLWC produced excellent results and performance in terms of surface resistivity, water penetration, water absorption, charges passed, and wear resistance, in the range of 18, 55, 51, 86 and 13 % respectively. This study suggests that CPF liners enhance the surface of concrete and improve its durability by decreasing the water-cement ratio at the cover region, reducing porosity.