High Performance Concrete Pavements
The objective of the study was to examine the benefits of using innovative pavement concrete mixtures for enhancing the flexural fatigue resistance and improving the shrinkage behavior of concrete pavement mixtures. The study was sponsored by Federal Highway Administration (FHWA) under "Test and Evaluation Project 30" (TE-30), "High Performance Concrete Pavement" (HPCP) and by the Maryland State Highway Authority (MSHA). In addition, the concrete industry is actively involved in this significant and innovative effort.
The study included extensive laboratory evaluation of several experimental fiber reinforced concrete and low shrinkage mixtures. Selected concrete mixtures from the laboratory study were used in the construction of test sections in the Salisbury bypass on US-50 for evaluating their performance under in-service loading and environmental conditions. Pavement instrumentation was also installed and includes: concrete strain gages for measuring slab surface stains under traffic loadings; linear variable displacement transducers (LVDTs) to measure concrete slab deflections under traffic; thermocouples to measure concrete slab temperature profile; vibrating wire gages to measure long term strains in the concrete slabs; and Whitmore plugs to measure changes in joint width. The constructed instrumented experimental pavement sections are currently undergoing load testing. Profile measurements of diurnal (temperature curling) and seasonal (moisture warping) slab changes are also included as part of the field monitoring program. The analytical portion of the study included finite element analysis (FEM) for both pre-construction predictions of expected pavement response and post construction monitoring of the experimental concrete slabs. Particular emphasis is placed on comparisons of stiffness degradation rates between the fatigue test section and the control section and on differences in temperature curling and moisture warping between the shrinkage test section and the control section.