Investigations on self compacting concrete using fly ash and light expanded clay aggregates

Compaction and curing both are equally important to achieve the desired strength and durability of concrete. To make concrete with a better surface finish, improved strength, and durability, it is essential to impart self compacting ability to concrete. Curing at an early age is to reduce the plastic shrinkage, to ensure adequate surface strength and surface zone durability. This study examines self-compacting concrete (SCC) that contains saturated light expanded clay aggregate (LECA) and fly ash aggregate (FAA). The effects of LECA and FAA on SCC were examined with flow properties, microstructure, compressive strength, acid resistance (HCl), sulphate resistance (MgSO4), and salt resistance (Nacl). The replacement of fine aggregate in the mixtures ranged from 0% to 25% with 5% interval by volume basis. Water filled LECA and FAA were also combined to produce SCC mixes. The findings demonstrate that substituting saturated lightweight aggregates for fine aggregate in SCC satisfied the filling ability, passing ability, and segregation resistance. The compressive strength of SCC with 15% LECA & FAA, under internal curing is higher by 1.84% & 13.35% higher than that of the control concrete (CMwc) at the age of 28 days. The F15 mix exhibited less weight loss and lesser strength loss in acid & sulphate. Also less weight gain and lesser strength loss in salt resistance. SCC made with LECA & FAA blends to promote internal curing offers technical and cost benefits in the construction industry.