Assessing the impact of curing on chloride penetration resistance of the concrete cover using sorptivity profiling

The chloride penetration resistance of the near-surface concrete cover depth is greatly influenced by the type and extent of curing provided. Very short or ineffective curing regimes result in less cement hydration and a more porous surface due to early evaporation of capillary water. The resultant depth-dependent capillary pore structure results in a depthdependent resistance to ingress of aggressive fluids, such as chloride solutions. Without reliable performance test methods for pre-qualification and quality assurance, minimum requirements for curing in specifications for concrete structures exposed to chlorides are typically prescriptive. In this paper, a series of modified rate of absorption tests is used to describe and quantify the effect of curing on the chloride penetration resistance of two concretes subjected to four different curing regimes, including accelerated moist curing. The proposed test method can be used to optimize curing for durability performance and allow credit for use of accelerated curing.