Impact of cementitious materials on the resilient modulus and damping ratio of weak subgrade

Abstract

Pavement structures are constantly subjected to cyclic loadings. The resilient modulus and damping ratio are frequently used to evaluate the stress–strain relationships and energy dissipation for pavement subbase and subgrade. This paper presents an experimental study on the resilient modulus characterization, and damping ratio calculation for hydraulic road binder (HRB) treated weak subgrade soils. Results indicated that similar to General Use (GU) cement, HRB significantly enhanced the soil’s resilient modulus by increasing internal structural stability in cementitious treated soils. Using current stress-dominated constitutive models, a fair prediction can be achieved for GU- and HRB-treated soils, especially for lower MR values (<500 MPa). In addition, there is a concave downwards relationship between the damping ratio, total axial stress, and resilient modulus, respectively. Under repeated loading, higher energy dissipation for treated soils is anticipated within a certain range of axial stress levels.Furthermore, the mean resilient modulus of GU- and HRB-treated soils highly correlated with moisture content and with the actual content of cementitious materials: cement clinker and ground-granulated blast-furnace slag (GGBFS) in the treated soils. Their contributions could be further quantified by efficiency factors. Overall, the outcomes of this study could be a reference for the future investigation and development of hydraulic road binders and contribute to the future substitute of conventional Portland cement in pavement engineering.