Impact-Compacted Noncement and Vibratory-Placed Noncement/Partial-Cement Concretes Containing Fluidized Bed and Pulverized Coal Combustion Residues

Abstract

The two-part research study presented herein evaluates fresh and hardened properties of vibratory-placed noncement/partial-cement concretes, as well as impact-compacted noncement concretes, containing various dosages of pulverized coal combustion fly ash and fluidized bed combustion spent bed. The results of Part I of this study on vibratory-placed noncement/partial-cement concretes revealed lower early strengths than those of reference concrete, whereas their late strengths (90 and 180 days) were similar to or higher than those of reference concrete. The selected noncement/partial-cement concretes produced higher expansion and lower drying shrinkage than those of the reference concrete. Abrasion resistance of noncement and partial-cement mixtures under dry conditions were better than that of the reference concrete, whereas opposite results were obtained under wet conditions. Laboratory results of Part II on impact-compacted noncement concretes revealed higher compressive strength and resistance to internal sulfate attack with increasing coarse aggregate content. The strength, stiffness, and resistance to abrasion and freezing/thawing of impact-compacted concretes improved with decreases in fluidized bed combustion (FBC) spent bed to pulverized coal combustion (PCC) fly ash ratios, whereas opposite results were obtained for sulfate-induced expansions.