Shrinkage cracking model for cementitiously stabilized layers for use in the mechanistic-empirical pavement design guide

Shrinkage cracking is one of the primary distresses found in cementitiously stabilized layers (CSL) of pavements. Shrinkage can cause cracking on the surface layer due to the bond between the surface layer and the CSL. Shrnkage of CSL includes autogenous shrinkage due to hydration, drying shrinkage due to loss of moisture, and thermal shrinkage due to low temperature contraction. The current methodology for analysis and performance prediction of CSL pavements in the Mechanistic-Empirical Pavement Design Guide (MEPDG) does not account for the prediction of shrinkage cracking. Given the importance of shrinkage cracking, incorporation of a shrinkage cracking model for CSL into the MEPDG will improve its analysis and design capability. This study uses dimensional analysis to develop a shrinkage cracking model to predict crack spacing and widths for CSL for stabilized fine and coarse-grained soils. The specific functional form of the shrinkage cracking model was developed based on field data as well as pilot-scale laboratory experimental results. It is found that the developed model for shrinkage cracking is effective in predicting shrinkage crack spacing and widths. Further calibration of the shrinkage cracking model is needed using additional field data.