Estimates of concrete transport properties by a two pressure water test Available to Purchase

The two-pressure-head sharp front (SF) model for unsaturated water transport was established to investigate the effects of drying temperature on the permeation properties of concrete. The proposed approach is capable of separating variations of obtained permeation properties caused by changes in moisture contents and/or microstructure. To verify this, two concretes with water/cement ratios of 0·65 and 0·35 were made. After curing, concrete samples were dried at four different temperatures ranging from 20°C to 105°C for 14 d. Sorptivity and water permeability were determined by the surface-mounted test through the SF model, as well as the standard water penetration method. The results show that an increase in drying temperature led to monotonic increases in sorptivity. Water permeability remained stable when the drying temperature was less than 40°C, but a significant increase was observed at temperatures beyond 60°C. The proposed method is a powerful tool that can be used to acquire variations in sorptivity and permeability before and after heat treatments, especially for the permeation properties of surface concrete.