ABSTRACT
ABSTRACT: WJE performed a four-year study of US produced prestressing strand aimed at determining why its bond properties have declined over the past 20 years. This study was funded by the National Cooperative Highway Research Program (NCHRP 10-62). WJE found that only certain manufacturers were making strand with deficient bond as a result of excess residual wire drawing lubricants and other factors. Surface tests were developed by the research that can be used to predict the bond properties of the strand. These tests were compared to transfer length tests and pullout tests of untensioned strand embedded in concrete and mortar. The tests developed by WJE are proposed for use in strand production facilities to qualify the bond properties of strand before it is shipped to customers.
