5.8 : 水質検査

If the quality of water available for preparing concrete is uncertain, its suitability is determined by comparing the setting time of cement and the compressive strength of mortar cubes made with the test water against those made with de-ionized or distilled water.

If the values obtained for setting time and compressive strength are within the permissible limits mentioned in the standards, the test water can be used to prepare concrete.

If brackish water is the only available option for mixing concrete, verifying that the concentration of chlorides, sulfates, and alkalis present in it are within the allowable limits prescribed in the standards is crucial in preserving concrete quality.

In case seawater is used for mixing concrete, the compressive strength of the concrete prepared with seawater and freshwater is tested, and the results are compared to ensure that the long-term stability is not reduced by more than 15 percent.

The possibility of water used for curing to cause staining on concrete surfaces can be determined by conducting performance tests that simulate wetting and evaporation on concrete surfaces.