Effects of Curing and Cement Type on Leak deterioration of Concrete in Water Tanks

Premature-deterioration of concrete in water storage tanks is a common problem in Ethiopia. The research aims at evaluating the effects of cement-types and wet-curing period on the resistance of concrete to leaching and leakage, based on compression, water absorption, and acid attack tests. To meet this objective, 54 concrete specimens with a grade of C-30 and water to cement ratio of 0.53 were casted in to two groups, each subjected to 3, 7, 10, and 28 days wet curing. The first group comprised 27 cubes made from OPC, while the second made from PPC. ANOVA was employed to test significances of variables on sorptivity. The sorptivity was higher for PPC than OPC for 10days and below cured specimens; however, well cured PPC exhibited better sorptivity performance at age of 58 and 98 days. ANOVA indicated that well-cured specimens made using PPC had significantly showed lower sorptivity than OPC age of 98 days. The resistance to acid attack of PPC was better than OPC. The finding showed that the selection of well cured-OPC and 10 days cured-PPC for concrete water tanks could be the cause for deterioration associated with leaching and leakage in concrete water retaining structures. The study contributes to the design of water storage structures.