Economical bridge overlays using waste latex paint

Polymer modified concrete (PMC) was introduced to address some of the disadvantages of normal concrete such as low tensile strength and vulnerability to chloride penetrability. Latex-modified concrete (LMC), a type of PMC where latex-based polymers are used, is usually utilized in special applications that require some of PMC's advantageous properties. Approximately 10% of all latex paint purchased in the United States becomes unused. This waste latex paint (WLP) contains volatile organic compounds (VOC), which makes it difficult and expensive to recycle. Using WLP in concrete as a replacement for styrene-butadiene rubber (SBR) has been found to produce a PMC comparable to LMC. WLP could produce a cost effective PMC as it can replicate the improved properties of LMC. Bridge overlays use LMC due to its durability under environmental conditions and traffic loads. Bridge overlays are subjected to chloride ion ingress, which may result in corrosion of the reinforcement and surface scaling of concrete. In this study, four concrete mixtures were evaluated. These mixtures consisted of a control mixture of normal concrete, one with SBR, and two with WLP. The experimental program included fresh properties as well as hardened properties. Results showed that a WLP mixture can meet the requirements for LMC bridge overlays. The success of the proposed technique can result in a total of one to two million cubic yards of inexpensive LMC produced in the United Sates yearly, with a substantial recycling of WLP.