A study on effects of water-cement ratio and crack width on chloride ion transmission rate in concrete

To study the effects of water-cement ratio changes and cracks on chloride ion transmission rate in cracked concrete, RCM method was adopted to accelerate the diffusion of chloride ion in cracked concrete, and the changes in chloride ion concentration and around the cracks are inferred by finite-element method. The test results show that as far as prefabricated cracks on concrete components are concerned, the width thresholds of two cracks on the concrete specimens with a water-cement ratio of 0.5 and 0.6 are 0.05 mm and 0.1 mm respectively, the width threshold of two cracks on the concrete specimens with a water-cement ratio of 0.4 is 0.05 mm and 0.2 mm respectively; and the results of numerical simulation show that the smaller the water-cement ratio is, the more significant effects of cracks on chloride ion transmission rate are. As a result, more attention shall be paid to the crack prevention, repairing and strengthening for high-strength concrete.