Plastic-viscosity-based mix design and effect of limestone on self-compacting concrete

The advantages of using self-compacting concrete (SCC) in comparison to traditional vibrated concrete are widely acknowledged. One of the key challenges in producing a consistent SCC mix lies in the ability to control its performance both in fresh and hardened states. Several methodologies are currently used for mix proportion design of SCC to achieve better quality and strength. In this work the consistency of a plastic-viscosity (PV)-based mix-proportioning method was investigated by exploring the fresh-state flow properties and hardened-state compressive strengths of SCC mixes produced using Portland limestone cement (PLC). SCC design mixes with target compressive strengths between 30 and 70 MPa were tested. It was found that while using the chosen PLC type, the mix-proportioning method based on estimation of PV failed to achieve the predicted compressive strength in the case of target mix strength of 60 MPa and above. The aim of this paper is to propose a procedure to mitigate this discrepancy by demonstrating that the quality and performance of the SCC produced using PV-based mix design can be influenced by the cement type used and this can also affect the target compressive strength achieved by the concrete mix.