Mitigating Transverse Joint Faulting in Jointed Concrete Pavement with Polyurethane Foam

A case study was conducted to assess the effectiveness of reducing transverse faulting on jointed concrete pavement with polyurethane foam (PF) on a principal arterial roadway with an average daily traffic of 15,800 with 20% trucks. The PF fault correction process entailed reducing faults to approximately 0.25 in. by saw-cutting the full depth through the joints and lifting the slabs with PF. A sampling plan was established: the entire project was measured for faulting and roughness by a high-speed profiler before and after the PF fault correction process. Three test sections with 10 slabs each were assessed with a falling weight deflectometer, A RRB walking profiler, and manual fault measurements. Seventeen cores were taken at various locations to obtain in-place PF samples. Statistical hypothesis testing was conducted to compare the before-and-after treatment effect of the PF process. Approximately 18% improvement in ride quality and 79% improvement in fault reduction were realized by the PF fault correction process. Unfortunately, the PF process severely affected load transfer efficiency, with a 43% increase in joints having poor load transfer and a 27% increase in joints needing load transfer improvement. It is reasonable to assume that these problems were caused primarily by saw-cutting through the joints and not by PF itself. Void potentials were increased slightly (8%) by the process.