Filler to improve concurrent flowability and segregation performance of concrete

AbstractPost-blending limestone (LS) filler to replace cement partially in concrete can lower the cost of production and embodied carbon. In order not to jeopardise the compressive strength, the water-to-cementitious materials (W/CM) ratio shall be kept. Because of the reduction in water-to-powder ratio, more superplasticiser (SP) is required to restore workability. Nonetheless, too much SP causes segregation. Hence, it is not clear if post-blending limestone will increase the segregation at similar strength and workability. In this study, various concrete mixes with post-blended limestone are tested for strength, flowability and most importantly, concurrent flowability-segregation performance. It is evident that at the same W/CM ratio, post-blending limestone increases the compressive strength and needs more SP to achieve similar flowability. Nevertheless, at the same water-to-powder ratio, the SP dosage required to maintain similar flowability does not change by too much. More importantly, the overall f...