OPTIONAL ELECTRIC METHODS INVESTIGATED AS SUBSTITUTES FOR THE S. G. CONCRETE MIX TESTER
Abstract
Efforts concerned a study of electrical methods for checking the water-cement ratio of concrete mixtures in order to control the quality of freshly mixed concrete. The proprietary S. G. tester previously was found incapable of detect ing variations in water-cement ratio as small as =0.01 (by weight). Accordingly, three optional electric methods were investigated: resistance to alternating current, power loss, and induc tion conductivity. Cement pastes, representing water-cement ratios ranging from 0.40 to 0.60, were used as the media. The reliability of the 1000-cycle alternating-current resistance method is inferior to that of the direct-current resist ance method utilized in the S. G. concrete mix tester. The power loss method and the induction conductivity method do not detect changes in water-cement ratio as satisfactorily as does the S. G. concrete mix tester. The direct-current resistance method, as exemplified in the pro prietary version of the S. G. tester, is con sidered the most promising. This electric method can serve satisfactorily in detecting water cement ratio (by weight) discrepancies within a =0.05 tolerance.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1963
- Accession Number
- AD0407906
Entities
People
- William R. Lorman
Organizations
- Naval Facilities Engineering Service Center