Effects of pore structure and water absorption on internal curing efficiency of porous aggregates

This paper presents the results of experimental investigation on desorption behavior and internal curing efficiency of porous aggregates with same size fraction from 2.36 to 4.75 mm, but different pore structure and water absorption. Water release rate and equilibrium remaining water of aggregates at different relative humidity were obtained in desorption test. Internal relative humidity, autogenous deformation, and compressive and flexural strength of plain and internally cured mortar were measured. Based on the analysis of results, it was revealed that, pore structure of the aggregate has intensity effect on equilibrium residual water, but indistinct on water release rate. The rate is linearly proportional to the reciprocal of volume water absorption of the aggregate. Pore structure and volume water absorption influence the internal curing efficiency of aggregates. Bigger pores and lower volume water absorption of aggregate facilitate the internal curing. Therefore, water release rate, as well as equilibrium remaining water, could be used to characterize the internal curing efficiency of aggregates.