A Wire Indent Profiling System for the Assessment of Crosstie Bond and Splitting Propensity

2019Research ResultsPDFTech ReportRR 19-06InfrastructureRailroad tiesPrestressed concreteHigh speed railindented wire geometrytransfer lengthcracking and splittingUnited StatesUnited States. Federal Railroad Administration. Office of Research, Development, and TechnologyUnited States. Federal Railroad Administration. Office of Research, Development, and TechnologyUnited States. Department of TransportationUS Transportation CollectionThis research result highlights a significant outcome from a task within a larger research project entitled, \u201cDeveloping Qualification Tests to Ensure Proper Selection and Interaction of Pretensioned Concrete Railroad Tie Materials.\u201d This research is performed by Kansas State University (KSU) and sponsored by the Federal Railroad Administration (FRA). The project started in 2015 and will continue through Spring 2019. This report highlights the development and testing of an automated, high-resolution, non-contact wire indent profile measurement system designed to measure geometric parameters of prestressed concrete reinforcement wire. This tool measures wire features that have a relationship to the bond and splitting performance of concrete crossties. This new technology overcomes the limitations of manual measurement techniques. The system can measure large segments of wire to yield statistically significant samples of indent parameters including indent depth, sidewall angle, sidewall area, and volume. This system represents a valuable tool to aid in identifying the key indent geometry features related to transfer length and cracking propensity, thereby ensuring high-quality bond and eliminating the potential for in-track tie splitting failures.75