Strength Properties and Shrinkage Behaviour of Roller Compacted Concrete

Abstract

Roller compacted concrete (RCC) is a dry concrete that exhibits zero slump. It gained popularity because of economy, strength and fast placement. Initially, the adoptability of RCC was limited to dam construction because of lower heat of hydration. RCC pavements have gained momentum in the last decade because of sustainability and initial cost benefits. Other benefits of RCC include higher structural capacity per unit thickness, higher sustainability rating and earlier opening to traffic. In order to attain sustainable development with RCC, some industrial waste products like fly-ash, ground granulated blast furnace slag (GBBS) can be used in high volumes as supplementary cementitious materials. In the present study, the effect of GGBS as partial replacement of Ordinary Portland cement (OPC) is explored in terms of strength properties and in service performance of RCC. The RCC mixes were prepared by using two types of coarse aggregates viz. crushed gravel (CG) and limestone (LS). The mix proportion of RCC was finalized based upon soil compaction approach. The RCC mixes were evaluated on the basis of compressive strength, split tensile strength, flexural strength, abrasion resistance and drying shrinkage strain. The effect of maximum ambient temperature i.e. 70 ± 2ºC on the shrinkage behaviour was also studied under two categories. Under the first category, specimens were subjected to a constant temperature of 70 ± 2ºC up to a period of 270 days; while in second category, temperature cycles of 12 hour heating at 70 ± 2ºC followed by a cooling at 10 ± 2ºC for a period of 12 hour were applied on the specimens for a period of one month. Further, all the strength properties, abrasion resistance and drying shrinkage of RCC were correlated to the compressive strength of RCC by performing different regression analysis. The strength properties results show that incorporation of GGBS into the RCC mix, leads to lower strength at early curing age, followed by strength higher than the control mix.