Rapid Concrete Repair

US Transportation Collection2019PDFTech ReportQuezada, IvanThomas, Robert J.Maguire, MarcUtah State University. Department of Civil and Environmental EngineeringUtah Department of TransportationUnited States. Department of Transportation. Federal Highway AdministrationUnited States. Department of TransportationUtah Department of TransportationUnited StatesAdmixturesCement additivesConcrete curingConcrete pavementsCreepDurabilityPortland cement concreteRepairingShrinkagecalcium sulfoaluminateUT- 19.0815-8507FinalInvestigations to develop a full depth durable concrete mixture (15 year life) to be used for pavement with four hour cure time and 4000 psi compressive strength that will minimize cracking were carried out. Current high early strength concrete mixtures have natural cracking and shrinkage problems due to the high content of cementitious material or their chemical components. Using IC allows for early strength, enhanced durability, reduced shrinkage and a better curing by providing water that can be absorbed by the cement past after the final set. Different OPC and CSA mixtures were prepared, with and without IC. Mixtures with IC had reduced early strength and delayed hydration, however, when combined with CSA cement, were able to obtain about 4000 psi of compressive strength in 4 hours of curing. Significant improvements in volume stability were also noted in the IC mixtures. Drying and creep shrinkage were reduced by factors of up to 15% and 30%, respectively. A CSA mixture with IC is recommended by the authors.133