Use of Shear Wave Velocity to Evaluate Curing of Cement-Stabilized Carbonate Quarry By-Products at Different Temperatures

Ongoing research at the Illinois Center for Transportation (ICT) is exploring sustainable use of quarry by-products (QB)—residual materials from stone quarrying—as pavement foundation materials. This study investigates how the chemical and mineralogical properties of aggregate QB affect their strength gain during extended cement hydration periods. The QB materials were classified as either dolomite or limestone, based on the Illinois Department of Transportation (IDOT) aggregate chemical testing methods. X-ray diffraction (XRD) analysis was conducted to identify the major and minor mineral phases within these materials. Bender Element (BE) sensors—shear wave transducers—were installed in 3% cement-stabilized QB specimens with varying chemical and mineralogical compositions to continuously monitor strength development during curing at two temperatures, 104°F (40°C) and 70°F (21°C), over a period of 4 months. Limestone QB specimens initially showed higher shear wave velocities (Vs) than the dolomitic QB, indicating a faster rate of hydration under both temperatures. However, over time, dolomitic QB specimens demonstrated faster increases in Vs, suggesting greater hydration and stiffness. This reversal trend indicates that the chemical and mineralogical compositions of dolomitic QB lead to distinct hydration reactions and formation of additional hydrated phases. Further analysis shows that curing lightly cement-stabilized specimens at an elevated temperature of 104°F (40°C) results in an average small-strain shear modulus (Gmax) that is 30% higher than that achieved at room temperature.