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The efficient repair and replacement of concrete pavements and bridge decks often requires a rapid setting material that can be placed, cured, and opened to traffic in a relatively short period of time. Frequently, temporary repairs are made using materials that are later found to be incompatible with the existing pavement, structures, and environment. This practice causes these materials to fail prematurely, frequently requiring re-repair. Research is needed to determine which rapid setting repair materials demonstrate the best behavior with rapid strength gain, low potential for cracking, and excellent durability. The objective of this research is to evaluate the performance of rapid setting cement-based repair materials that will be used in applications ranging from the patching of concrete pavements and bridge decks to the paving of critical intersections and pavements that can not be closed for extended period of time. Consideration was given to parameters such as rate of strength (stiffness) gain, volume stability, bond, and the environment the material can be placed in. It was observed that the repair materials investigated in this study show a wide range of properties. All of the materials tested had a long term compressive strength of over 4000 psi, a modulus of 3,000,000 psi, and set between 10 minutes and 2 hours. Results of the bond strength tests demonstrated higher bond strengths in shear than tension. In addition these materials showed greater variability in the tensile bond strength than they did in shear. The materials showed a wide range of unrestrained length change (as measured from the time of set) from materials that expanded to materials that shrank by as much as 800 ìå at 28 days. In addition to monitoring unrestrained length change, the restrained ring test was used to assess the cracking potential of these materials when they were restrained. While several materials exhibited expansion and no residual stress development, other materials demonstrated residual stresses that were nearly 75% of the tensile strength at 7 days. It is recommended that Table 5.1 be used for the selection of laboratory mixtures to investigate for use in the follow-up study on evaluating the field performance of joint repairs. more...