Applied mixture optimization techniques for paste design of bonded roller-compacted fibre reinforced polymer modified concrete (BRCFRPMC) overlays

The overall composite performance of concrete is generally contingent on achieving the right proportion of blend. The use of mixture experiments provides a flexible, easy, and quick way of optimizing multi-component materials of this nature. This paper describes the use of optimization techniques within the concept of material mixture experiments for proportioning and designing the paste (P) component of a bonded roller compacted fibre reinforced polymer modified concrete. By constraining the range of variability of the paste constituents, a feasible design space was created with 13 experimental points treated based on the required structural and elastic properties of the overlay. The optimum consistency-time for full consolidation and composite behaviour with the substrate ordinary Portland cement concrete (OPCC) was established between 34.1 and 34.9 s, while the resulting apparent maximum density achieves between 97.1 and 98.0 % of the theoretical air-free density. The tensile and shear interfacial tests performed on the optimum mixture overlay also exhibited good bonding capability with the substrate OPCC. The combined effects of curing age and surface texture on bonding were also underlined.