Concrete in biological activated carbon (BAC) adsorption pool deteriorates more rapidly than those in other water purification facilities. In this study, concrete cores were taken from BAC pools in two actual water purification facilities with different concrete mix proportion and in service period, and then they were investigated on physical and chemical properties. After that, the deterioration factors on the concrete in BAC pool were estimated based on analysis results of concrete cores and water quality. In addition, mortar specimens with different binder types were prepared as sprayed repairing mortar for surface concrete in BAC pool, then they were exposed into a tank simulating a BAC pool for about 7 years in order to investigate resistance of mortar specimens to deterioration in the BAC pool. As a result, it is found that the mortar specimen with decreasing of calcium hydroxide content shows higher resistance to deterioration in BAC pool because of low leaching of calcium ion from the specimen.

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[in Japanese]

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[in Japanese]

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