Characteristics of Concrete Incorporating Waste Marble Powder

Abstract

In the present study, the influence of using marble waste as fine aggregates in concrete is investigated. Seven mixes were prepared by varying the replacement levels of marble waste from 10 to 60%. The w/c ratio of the mixes was kept constant at 0.5. The effect of using marble waste aggregates is investigated in terms of workability, mechanical strength of concrete, permeation properties and durability properties of concrete. The various durability properties investigated in the study included abrasion resistance of concrete, drying shrinkage, resistance of concrete when subjected to external exposure to severe sulphuric acid and sodium sulphate exposure. All the studies are supported by micro-structural analysis of concrete. Test results indicate that marble waste can be incorporated into concrete to improve its strength and permeation properties, with the maximum improvement obtained at 40% replacement level. The improvement in properties of concrete with the incorporation of marble waste can be attributed to better filler effect provided by marble waste, due to presence of more fines in the particle size range of 1.18mm - 300and#956;m, which led to refinement of pore structure. Along with this, the angular sizes of marble waste aggregates helped in better bonding and improvement in interstitial transition zone of the resultant mix. At the chemical level, marble waste improves the binding ability of the mix. The reaction between calcite present in marble with C3A of cement provides a compact structure and helps in improving binding capability of the concrete matrix. Micro-structural analysis also revealed densification of concrete matrix, which is attributed to refinement of pores because of both physical and chemical changes in the concrete matrix. The fact that marble is largely an inert material and has filler effect on the properties of the resultant mix, is confirmed from the SEM and XRD analysis which shows major phases formed in all mixes remained same, irrespective of the replacement levels of mar