Optimization of a pavement instrumentation plan for a full-scale test road : evaluation.

PDFTech ReportBDV31-977-04OptimizationInstrumentationTest sectionsEvaluationFiber opticsSensorsData qualityStrain measurementTemperature measurementCostsFloridaFlorida. Dept. of TransportationRice, Jennifer A.University of Florida. Dept. of Civil and Coastal EngineeringUS Transportation CollectionA 2.5-mile, concrete test road is planned for construction by the Florida Department of Transportation (FDOT) in2016. To support the goals of the test road, a comprehensive instrumentation system is required to providereliable data over a long period. The unique challenges posed by the geographical location and configuration ofthe test pavement require sensors that can employ long sensor cables without compromising data quality andhave limited susceptibility to damage from lightning strike. The research conducted for this report investigatedthe availability and performance of traditional and emerging instrumentation approaches for the embeddedmeasurement of concrete strains and temperatures. Fiber optic sensors possess features that overcome thespecific challenges of the proposed test pavement and were chosen for experimental evaluation alongside thecopper-based sensors that have been routinely employed by the State Materials Office (SMO). The candidatestrain sensors were initially evaluated in a series of non-embedded tests to assess their measurement capabilities,noise susceptibility, temperature sensitivity, and ease of installation and use. A small concrete test slab was thenconstructed for longer-term evaluation of the various sensor types in conditions similar to those of the proposedtest road. The duration of the test slab experiments (several weeks) exposed the slab to environmentally-inducedloads and dynamic wheel loads imposed by a Heavy Vehicle Simulator. The resulting strain and temperaturemeasurements were analyzed to assess the accuracy, repeatability, and robustness of the sensors. The copper andfiber optic strain sensors yielded similar measurement results; however, the fiber optic sensors provided a morestreamlined installation and setup process. The cost of the individual fiber optic sensors is higher than the coppersensors; however, the fiber optic sensors require fewer data acquisition (DAQ) units. A hybrid instrumentationplan (copper/fiber optic) is suggested to optimize instrumentation costs while ensuring the measurement needsand data quality requirements of the test pavement are met