Test Method Evaluation and Model Development for Erodibility Properties of Cementitiously Stabilized Layers

Abstract

Abstract Cementitiously stabilized layers (CSL) have been used extensively by highway agencies over the years. The erosion of CSL can cause several distresses in flexible and rigid pavements. The three necessary conditions for the occurrence of erosion are heavy loads, sufficient moisture, and the presence of erodible materials. The Mechanistic-Empirical Pavement Design Guide (MEPDG) provides a methodology for the analysis and performance prediction of pavements that incorporate CSL. However, test methods and models that specifically address the erosion of CSL have not yet been incorporated into the MEPDG. This study evaluates the existing test methods for erosion, including wheel tracking, manual wet-dry brushing, rotational shear device (RSD), jetting, a vibration table, or cyclic impact erosion (CIE), or combinations thereof. It is found that a CIE test is a robust test procedure that is used to quantify the erodibility of CSL. Based on the laboratory results from a CIE test, an empirical model that combines top-down compressive fatigue and erosion is developed to predict the erodibility of CSL. It is found that the developed model is effective in predicting both the top-down compressive fatigue and erosion of CSL. This test method and prediction model are recommended for incorporation into the MEPDG.