Engineering Behavior and Microstructure of Soil Stabilized with Cement Kiln Dust

Abstract

A laboratory study was undertaken to evaluate the effectiveness of different percentages of cement kiln dust (CKD) as a soil stabilizer, relative to the implementation of new Mechanistic-Empirical Pavement Design Guide (MEPDG). Cylindrical specimens were compacted and cured for 28 days in a moist room having a constant temperature and controlled humidity. After curing specimens were tested for resilient modulus (Mr), modulus of elasticity (ME) and unconfined compressive strength (UCS). The study revealed that the values of Mr, ME and UCS for the CKD-stabilized specimen increased with CKD amount. Reaction products due to chemical reactions are clearly observed in the soil voids based on the micrographs obtained using scanning electron microscope (SEM), and they are responsible for the increase in modulus and strength.