Influences of freeze–thaw cycle and curing time on chloride ion penetration resistance of Sulphoaluminate cement concrete

In this paper, the influences of freeze–thaw cycle and curing time on the chloride ion penetration resistance of Portland and Sulphoaluminate cement concretes were researched. Results show that freeze–thaw cycle and curing time have significant influences on chloride ion penetration resistance of the two cement concretes. Although the chloride diffusion coefficients of the two cement concretes decrease gradually when curing time increases, it is much lower for Sulphoaluminate cement concrete. The chloride diffusion coefficient and chloride ion penetration depth both increase obviously after the two cement concretes were subjected to the freeze–thaw cycles, which indicates that the freeze–thaw cycles can accelerate the chloride ion diffusion into the two concretes. Under the same freeze–thaw cycle and curing time, Sulphoaluminate cement concrete has much better chloride ion penetration resistance than Portland cement concrete. Comparing with Portland cement concrete, the variation rates of chloride diffusion coefficient and chloride ion penetration depth both increase more rapidly for Sulphoaluminate cement concrete after freeze–thaw cycle.