Effects of temperature variations on the deflections of airfield jointed plain concrete pavements

Abstract

This paper aims to study the influences of temperature variations on airfield jointed plain concrete pavement (JPCP) deflections. The maximum deflection at the transverse joint (D0j), the maximum deflection at the corner of a slab (D0c), and the deflection basin at the centre of a slab were considered. The in-situ deflection measurements at three civil airports were conducted over a 24-hour period and numerical simulations for JPCP at a civil airport were performed as well. The results indicate that the temperature change slightly affects the deflection basin at the centre of a slab unless the positive temperature gradient in the slab increases to exceed a certain critical value. But both D0j and D0c are significantly affected by temperature variations. The results of in-situ tests show that D0j (or D0c) is almost stable from 1 pm and 5 pm in a day. At other times of one day, there is a strong negative liner correlation between D0j (or D0c) and the pavement surface temperature during the heating period and the cooling period, respectively. The results of numerical simulations reveal that both D0j and D0c gradually increase with the increase of the average temperature. The results of numerical simulations also suggest that a critical negative/positive temperature gradient exists at the transverse joint while there is a critical positive temperature gradient at the slab corner. Besides, all the critical temperature gradients are seldom affected by the average temperature. When the temperature gradient exceeds the critical value, D0j, D0c and all values of the deflection basin have a strong positive linear correlation with the temperature gradient. Keywords: Jointed plain concrete pavement, Falling weight deflectometer, Numerical simulations, Temperature variations, Deflections