Three standard mortar cubes were made using nonpotable water available at the job site, and three others were made using potable water. The cubes were tested for compressive strength after 7 days of curing and produced the failure loads in kips shown in Table P6.23.
The Vicat test was conducted on the cement paste made with the questionable water and showed that the set time was 45 minutes more 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 P6.23
Nonpotable Water | Potable Water |
15.8 | 16.9 |
16.4 | 18.7 |
16.6 | 17.4 |
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