Curling generally results from the temperature differential across the concrete slab thickness. Curling induces stresses in the pavement slab that may contribute to early-age concrete cracking. This study deals with the field measurement of temperature and curling on a newly built jointed plain concrete pavement. The pavement section consisted of a 12-inch concrete slab, 4-inch bound drainable base, and 6-inch limetreated subgrade. Temperature data was collected at five different depth locations across the thickness of the concrete slab with the digital data loggers embedded in the slabs. Curling was measured on five different days in the summer and fall with a simple setup. The results show that both upward and downward curling increase as the temperature differential increases. The magnitude of curling deflection resulting from a particular positive temperature differential is slightly higher than that resulting from the same negative temperature differential value. The in situ curling can be simulated with a properly built finite element model. Since temperature differential has a significant influence on curling, the effect of curling can be mitigated at an early age of pavement concrete with proper measures, such as enhanced curing.
Abstract