Four standard mortar cubes were made using nonpotable water available at the job site, and four others were made using potable water. The cubes were tested for compressive strength after 7 days of curing and produced the failure loads in kilograms shown in Table P6.24. Also, the Vicat test was conducted on the cement paste made with the questionable water and showed that the set time is 1_2 hour less than the set time of paste made with potable water. Based on these results, would you accept that water for mixing concrete according to ASTM standards? Explain why.
TABLE P6.24
Nonpotable Water | Potable Water |
6909 | 7773 |
6591 | 7400 |
6302 | 7599 |
7227 | 7364 |
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