Abstract:

Semi-rigid base course materials are widely used in the high-class highways in China. If shrinkage strains of semi-rigid base course materials caused by the variations of temperature or/and moisture exceed the ultimate tensile strain that the material can bear, it will fracture, and the service performance of the pavement will be influenced. Choosing suitable shrinkage test method to study semi-rigid base course materials’ shrink performance has high practical significances. For the shortage of the conventional shrinkage measuring method, the lab shrinkage experiments on a kind of typical cement stabilized macadam are studied by the digital image correlation method(DICM), the early change laws of shrinkage strains are analyzed; by calculating correlation of the images captured before and after deformation, DICM is employed to obtain the whole-field shrinkage deformation. Comparing with the conventional shrinkage test results, the repeatability is fine, the stability is good and the accuracy is higher.

Key words: shrinkage test, cement stabilized macadam, digital image correlation method, deformation measurement