Development of Self-Consolidating Concrete for Thin Wall Applications Including Validation

This study presents a self-consolidating concrete mix developed for thin wall construction. Casting of vertical thin concrete walls requires a stable, pumpable, and highly flowable mix. The developed mix has increased fine-to-coarse aggregate ratio, 20% fly ash replacement, a low $w/cm$ ratio, a superplasticizer, an accelerator (optional), and a viscosity modifying admixture. A special placement method was designed for pumping the concrete from the bottom of the vertical wall form. Concrete walls of 75-mm thickness reinforced with one or two steel grid layers were cast and loaded to failure under one-way and two-way bending configurations. The one-way slabs resembled portal frames and were loaded with a line load along the centerline. Plastic hinges formed at the centerline of the one-way slabs and then at a corner, where reinforcement was greater. The two-way slabs were loaded with a small-area concentric uniform distributed load. A yield line strength analysis was performed and matched quite closely the experimental capacities. It was concluded that it is possible to cast high strength vertical thin walls with self-consolidating concrete by pumping from the bottom of the form.