Implementation of Polyester Concrete Grout in Dowel-Bar Retrofit of Jointed Plain Concrete Pavements

Dowel bar-retrofit (DBR) has been used in United States and elsewhere over the past 20 years. The California Department of Transportation (Caltrans) started implementing the dowel bar retrofit program in 1998 with the construction of a demonstration project on Interstate 80 near Colfax, California which was followed by a series of projects on various roads throughout California. Afterwards, and within few years, distresses were observed on projects that were constructed by various contractors using different cementitious grouts. The types of distresses observed included cracking of the grout material, surface erosion, debonding at the grout-pavement interface and grout pop-out. Most of these problems could be attributed to construction quality issues. The extent of the damage resulted in an investigation and halted the dowel bar retrofit program for several years. Laboratory tests using the bending beam test superior performance with the use of polyester polymer concrete (PPC) grout. As a result of these efforts, over 60,000 dowels were successfully installed on US Highway 50 using polyester concrete grout. The paper will focus on the successful implementation of polyester concrete grout in the dowel bar retrofit of jointed plain concrete pavement on highway US 50 near Sacramento, California. Lessons learned from this implementation are presented in this paper.