A laboratory experiment on warping behaviour of large-scale concrete specimens influenced by moisture conditions

초록

The upward warping of concrete pavement slabs caused by differential drying shrinkage can deteriorate the smoothness of road surfaces and cause cracks, negatively affecting user comfort and safety. Therefore, in this study, a laboratory experiment was conducted to investigate the effects of differential drying shrinkage on the warping behaviour of jointed concrete pavement slabs. Large-scale concrete specimens were fabricated to measure the longitudinal strain and the vertical and longitudinal displacements according to the distance from the fixed point and the age of the specimens. The experimental results revealed significant displacement and strain differences for the specimen with the bottom submerged in water owing to differential drying shrinkage. The upward displacement and difference in the contraction strain of the specimen with a submerged bottom increased sharply toward the free end. Additionally, the overall behaviour of the specimens was analysed to estimate the early age behaviour of jointed concrete pavement slabs according to moisture conditions. To validate the experimental results, the curvatures of the specimens were calculated, and the resulting vertical displacements were compared with the measured displacements. Further research is required to mitigate the differential drying shrinkage, which is a key factor in the warping of jointed concrete pavements.

키워드