Shear Behavior of High-Volume Fly Ash Concrete versus Conventional Concrete

Abstract

The production of portland cement—the key ingredient in concrete-generates a significant amount of carbon dioxide. However, due to its incredible versatility, availability, and relatively low cost, concrete is the most consumed manufactured material on the planet. One method of reducing concrete’s contribution to greenhouse gas emissions is the use of fly ash to replace a significant amount of the cement. An experimental investigation was conducted to study the shear strength of full-scale beams constructed with both high-volume fly ash concrete (HVFAC)—concrete with at least 50% of the cement replaced with fly ash—and conventional concrete (CC). This experimental program consisted of 16 beams (12 without shear reinforcing and four with shear reinforcing in the form of stirrups). Additionally, three different longitudinal-reinforcement ratios were evaluated within the test matrix. The beams were tested under a simply supported four-point loading condition. The experimental shear strengths of the beams were compared with the shear provisions of both American Concerte Institute Committee 318 and AASHTO LRFD Furthermore, statistical data analyses (both parametric and nonparametric) were performed to evaluate whether or not there is any statistically significant difference between the shear strength of the HVFAC and the CC beams. Results of these statistical tests show that the normalized shear capacity of the HVFAC is higher than the CC for the beams tested in this investigation.