The effect of quarry waste dust and reclaimed asphalt filler in hydraulically bound mixtures containing plasterboard gypsum and GGBS

Abstract

In this research, a novel Hydraulically Bound Mixture (HBM) is successfully developed using waste minerals and industrial by-products to fully replace cement in road (base) and foundation materials. HBM is a mixture that sets and hardens by hydraulic reaction and usually has compaction by rolling. The materials used were reclaimed asphalt filler (RAF), quarry waste dust (QWD), plasterboard gypsum (PG) and ground granulated blast furnace slag (GGBS). A statistical mixture design programme – Minitab 18, was used for the design of the experiment. Compressive strength, high pressure flow tests and freeze/thaw tests were carried out to determine the mechanical stability of the by-product binders and performance determined in the strength development by time. It was concluded that cement can be 100% replaced with the named industrial by-products. Test results revealed that the presence of GGBS is highly beneficial between 40 and 60% replacement by weight. Strength development on the hydraulic paste comprising of this GGBS replacement has a reduced strength during the first 28 days. After 28 days and up to 90 days when the maximum strength is gained, strength increases with the presence of GGBS of up to 60%. The results showed that the top four mixes in the two groups discussed in this research meet the standard requirements for road (base) and foundation materials.