Mechanisms of 3-D Internal Cracks Growth and Coalescence in PMMA
Several experiments undertaken on cement and mortar samples with internal cracks of different shapes and sizes demonstrated that 3-D cracks growth in compression was qualitatively different from the 2-D cases. This paper employs pre-existing cracks in frozen PMMA（polymethylmethacrylate plastic） which are produced by the mechanical method to analyze the evolution of the boundary effect of PMMA and to study the mechanisms of cracks growth and coalescence. In the experiments, 3-D cracks are tested under uniaxial compression and finally draw two conclusions about failure mechanisms of PMMA and brittle materials.
M. L. Wang and X. Yang, "Mechanisms of 3-D Internal Cracks Growth and Coalescence in PMMA", Applied Mechanics and Materials, Vols. 130-134, pp. 3912-3915, 2012