Environmental effects on development of pavement joint cracks

A test road consisting of jointed plain concrete pavement divided into 22 sections was constructed by the Korea Highway Corporation to investigate the environmental effects on the development of joint cracks. These 22 sections were observed for approximately three to seven weeks after construction. The pavement placed in the morning presented a higher rate of crack development at the saw-cut joints, due to a positive built-in temperature difference. Additional joint cracking was delayed for a few days after construction because the pavement was exposed to rainfall. For pavement sections placed in the afternoon, drying shrinkage appeared to have a greater effect on crack initiation at the saw-cut joints than temperature did up to three or four days after placement, when tensile creep had decreased sufficiently. The effect of joint crack time on the long-term joint behaviour was also investigated in the test road two years after placement of the concrete.