A sandy soil SW is mixed with Portland cement and tested for

A sandy soil (SW) is mixed with Portland cement and tested for durability requirements. The results are tabulated below. What would you recommend as the minimum cement 4. content based on these test results? Why? %loss Cement Content % | 7.0 8.0 9.0 10.0 11.0 wet-Dry tests 12.5 11.5 9.6 8.5 8.3 Freeze-Thaw 16.5 12.9 8.9 6.1 5.9

Solution

The percentage loss of strength after wet dry tests and freeze-thaw cycle which is minimum at 11.0 percentage of cement which is 8.3 % and 5.9 %.So, without considering the code of practice, the minimum cement content should be 11%. According to American Association of State Highway and Transport officials, the minimum retained strength should be 80% of the total strength. If this code of practice is considered, the minimum cement content should be 7% with 87.5% (100-12.5) and 83.5% (100-16.5) of retained strength with respect to wet dry and freeze-thaw cycles which is greater than 80%.