Characterisation of full-depth reclaimed pavement materials treated with hydraulic road binders

Abstract

Hydraulic road binders (HRB) are factory made blends which are composed of a substantial amount of supplementary cementitious materials and portland cement. Previous studies indicated that the use of chemical stabilizers containing supplementary cementious materials is a sustainable approach that can reduce carbon dioxide (CO2) emission by 5−25%. Thus, the use of HRB in full-depth reclamation process could make the practice more sustainable if strength, stiffness, and durability of treated materials are not compromised. The primary objective of this study is to evaluate the mechanical properties of full-depth reclaimed pavement materials treated with hydraulic road binders. The study was conducted in the form of comparative assessment by using full-depth reclaimed pavement materials treated with General Use (GU) cement as a control mix. For this study, three types of full-depth reclaimed pavement materials and four types of cementitious binders, including GU cement, were used to make eleven different types of mixes. Unconfined compressive strength, modulus of elasticity, and indirect tensile strength tests were used to assess the mechanical properties of the eleven mixes. The test results indicated that hydraulic road binders could provide equivalent strength and stiffness as GU cement. The study also revealed the HRB content, required to attain equivalent strength and stiffness as GU mixes, is the same or less than GU cement content. Based on the study findings, hydraulic road binders can be sustainable alternative binders that can replace GU cement in full-depth reclamation process without compromising the structural function of the treated layer.