FORMATION AND FAILURE BEHAVIOR OF OPEN-GRADED FRICTION COURSE AT LOW TEMPERATURES

To study the deformation and failure behavior of the open-graded friction course (OGFC) before cracking at low temperatures, a four-point bending test of the trabecula was conducted, and the deformation process was monitored by the digital speckle method (DSM). The distribution law of the strain field of the trabecular specimens was analyzed. The horizontal strain field gradually changed from a uniform distribution to a strain concentration area with loading. The crack initiation time, crack initiation strain, and deformation period were obtained from the strain curve. The combination of stress reconstruction and DSM makes the stress measurement of the OGFC more authentic.