Styrene-Butadiene Latex Modifiers for Bridge Deck Overlay Concrete.

摘要

Styrene-butadiene (S/B) latex modified concrete overlays are being used to protect new bridge decks from rapid deicer-borne chloride intrusion and also in bridge deck rehabilitation efforts. The purposes of this research were to evaluate several commercially-available S/B latex modifiers for bridge deck overlay concrete;and to develop chemical specifications for the material, a prequalification program to permit evaluation of other S/B latex modifiers which become available,and a certification program to insure the user receives a prequalified product. The chemical and physical properties of the latex emulsions were studied (percent solids,percent butadiene,particle size,surface tension,viscosity,etc.) and the material from each manufacturer was fingerprinted using infrared spectroscopy. The physical properties of concrete made with each material were also determined (workability,strength-compressive, flexual and bond,freeze-thaw and scaling resistance,and chloride permeability). In general,the studies showed that the following materials exhibit similar properties and thus would be expected to perform similarly as bridge deck overlays:Modifier A -Dow Chemical Company; Deco-Rez 4776 -General Polymers Corporation; Thermoflex 8002 - Reichhold Chemicals,Inc.;and Arco Dylex 1186 - Arco Polymers,Inc. The prequalification procedures given in the report are suggested for use in evaluating other S/B latex emulsions offered by industry. The certification procedures are suggested for use to insure that each production batch of emulsion is similar to an emulsion which was prequalified.