Effect of Super Absorbent Polymer Particles on Autogenous Shrinkage and Compressive Strength of Concrete

Autogenous shrinkage(AS) is an important factor that results in early age crack of high strength concrete.Effects of super absorbent polymer(SAP) dosage and its entrained water on AS and compressive strength of concrete were studied.Results indicate that if dry SAP dosage is within 0.5% of cementitious materials by weight,pre-saturated SAP particles could effectively mitigate AS with little strength loss.Mechanism of SAP on AS and compressive strength were analyzed by investigating internal relative humidity(IRH) change of concrete incorporated with pre-saturated SAP.SAP could delay IRH decline and have an effective internal curing to reduce AS.But when SAP dosage exceeds 0.5%,internal curing effect improves slightly and compressive strength loss becomes serious.