Investigations on Latex-Modified Bridge Deck Overlay Concrete

摘要

The interim report provides current results on a continuing project design to examine the effects of fly ash incorporation in latex-modified concrete designed for bridge deck overlays. Concretes batched with commercial styrene-butadiene latex and incorporating 15 percent and 25 percent of fly ash were prepared and the results of compressive strength, flexural strength, and chloride permeability testing over a six-month period are reported. Four different Indiana fly ashes, including one Class C and three Class F ashes of varying properties were used. It was found that the fly ashes did not seriously degrade the development of strength in the latex-modified concretes, and actually improved the chloride permeability test results significantly. Some variation was found between the effects of the different fly ashes, the particular Class C ash used showing generally superior effectiveness, but the differences did not appear to be of great practical importance. The differences between the results for 15 percent and 25 percent fly ash treatment levels for a given fly ash were not very great. Research is continuing on several other aspects of the behavior of latex-modified concretes incorporating fly ash.