Recycling of ternary industrial by-products as cement replacement material and its influence on the durability of restored pavement potholes

Abstract

To repair deteriorated cement pavements effectively, a cement-based repair material incorporating silica fume (SF), granulated blast furnace slag (GBFS) and desulphurised gypsum (DG) ternary industrial by-products were prepared. The mechanical properties and durability of composite members restored by the repair material were investigated based on different repair positions in the pavement potholes. The results show that the addition of SF–GBFS–DG ternary industrial by-products in cement increased the flexural, compressive and bond strengths of the repair mortars. Moreover, the incorporation of the ternary by-products in cement increased the flexural and compressive strengths of the composite members regardless of the edge-, corner- or middle-bond treatment in the potholes and enhanced the resistance to ions penetration and water absorption of the composite members. Furthermore, the addition of the materials in cement increased the hydration products such as ettringite and calcium silicate hydrate, refined the pore structure and decreased the Ca(OH)2 content.