University of California Pavement Research Center

Moisture-related shrinkage is regarded as one of the phenomena that has the largest impacts on the performance of jointed plainconcrete pavements. Still, most mechanistic-empirical design methods oversimplify or ignore predictions of moisture-relatedshrinkage and its effects on concrete pavements. This study evaluates how moisture-related shrinkage accumulates in concretepavements and the structural response of the concrete pavement slabs to the shrinkage action. The experimental data comefrom six thin concrete overlay of asphalt pavements that were instrumented with sensors to measure the structural andhygrothermal response of the slabs due to temperature and moisture-related actions. After an analysis of the predictions madeby current shrinkage models, a new shrinkage model was developed. This new model, which is based on the incremental-recursive application of the B4 shrinkage model, provided an excellent prediction of the moisture-related shrinkage measured inthe field. In addition, the structural response of the concrete pavement slabs under the moisture-related shrinkage action wasanalyzed using the finite element method (FEM). The FEM analysis based on the standard practice for concrete pavementmechanistic-empirical modeling resulted in unrealistically high tensile stresses. However, much smaller stress values were foundwhen the time-dependent (viscoelastic) behavior of concrete and asphalt was considered.