Abstract：Non-interpenetrated crack concrete specimens are used to study the crack developing process in non-interpenetrated crack media under uniaxial loading. The specimen is a cubic pillar of 10 mm×10 mm×21 mm in size with non-interpenetrated pre-existing cracks which are inclined to the loading direction at 30°，45°，60°，90°，respectively. The in-time CT scanning is made in the process of uniaxial loading and 3D CT images are reconstructed to detect crack developing process. Based on the CT images，damage isoline of scanning section is drawn to describe quantitatively the process of crack developing. The study shows the different effects of two kinds of damage (crack and micro crack) on crack developing process.
