Experimental Investigation Of Corrosion-induced Cover Cracking Of Fly Ash Concrete

The corrosion of reinforcing steel bar in concrete is one of the major problems in the study of durability of concrete. The durability of fly ash concrete structure has aroused widespread concern as its extensive use in practical engineering, and the corrosion-induced cover cracking is the basis of durability assessment and service life prediction. Therefore, it is an urgent requirement of engineering to investigate the amount of steel consumed to cause cover cracking of fly ash concrete, which, is of great practical significance to make sure the sustainable development of national economy.In this paper, factors of cover cracking of fly ash concrete have been analyzed through an accelerated corrosion test. The results indicate that the weight loss of bar increases as the water-to-binder (w/b) ratio or the fly ash content increases. The cover-to-diameter (c/d) ratio is an important parameter against cover cracking. As the cover-to-diameter (c/d) ratio increases, the amount of corrosion needed to crack the cover increases. At last, a model to calculate the ratio of corrosion which taking into account of the factors above was proposed by non-linear regression according to the test data. The results calculated by the formula agree well with of the measured results.