Reusing of marble and granite powders in self-compacting concrete for sustainable development

Huge amounts of solid wastes are generated every day from marble and granite industry. Up to now, most of these wastes are landfilled causing serious environmental problems. With increasing the environmental awareness, it is essential to explore alternative solutions to waste disposal problem. This paper investigates the possibility of using various types of waste powders, generated from marble and granite industry, as mineral additives in self-compacting concrete (SCC). For this purpose, three types of waste powders were used; marble powder, granite powder and mixed powder. The experimental program included two phases. The first phase was the preliminary investigation to optimize the amount of the used mineral additives to cement content at which the highest compressive strength is achieved with acceptable flowability. In the second phase, the fresh and hardened properties of SCC were investigated. Slump flow, V-funnel, and J-ring tests were conducted to assess the self-compactability properties of fresh concrete, while compression, splitting tensile, flexural, water absorption and sulfate attack tests in addition to microscopic investigations were conducted to evaluate its hardened characteristics. The results indicated that high volumes of the investigated waste powders (up to 50% by weight of 400 kg/m3 cement content) could be used successfully as mineral additives in the production of SCC. In general, SCC incorporating mixed powder showed the superior performance followed by granite powder mixes, while marble powder has a marginal effect on the performance of hardened concrete. However, silica fume could be used for the enhancement of marble powder performance.