ASTM C 1202 tests were conducted at various ages with the corresponding surface resistivitytest and the results were compared. Samples tested included field and laboratory preparedsamples. The laboratory test matrix tested several mixtures common to Louisiana at a widerange of water to cementitious materials (w/cm) ratios to evaluate the range of the surfaceresistivity meter. The surface resistivity measurements correlate well with rapid chloridepermeability measurements across a wide range of permeability values and sample testing ages.Suitable correlations were found to exist between both the 14-day and 28-day surface resistivityvalues and the 56-day rapid chloride permeability values. The variability of the surfaceresistivity meter results are usually less than those from the rapid chloride permeability test. Thesurface resistivity meter was also able to identify great differences in w/cm ratios for the samemixtures. The surface resistivity meter was determined to be user friendly. The preliminary costbenefit analysis showed that implementation of the device will save the Department about$101,000 in personnel costs in the first year. It is estimated that contractors will save about $1.5million in quality control costs. The cost benefit ratio for this project is estimated to be about 15.A Louisiana Department of Transportation and Development (LADOTD) Test Requirements(TR) Procedure, TR 233, has been developed and implementation of the surface resistivitydevice has begun.
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