2007 年 56 巻 10 号 p. 970-976
Compressive loading tests using acrylic acid resin and mortar specimens are conducted to research the fracture of materials with a macroscopic discontinuity under the compression loading in this study. The new types of specimen shape that can produce mode II and mode III deformation are used. The fracture takes place after crack is closed, that is, under the condition that the each crack surfaces are contacted. The fracture under mode II deformation occurs with a well-known wing crack for all specimens. In the experiments under mode III deformation using mortar specimens, the fracture surfaces include partly the fracture surface along the initial crack surface. But almost fracture surfaces are made by the fracture pieces related to the splitting. In the mode III experiments with an acrylic acid resin specimens, the fracture near the crack tip has the coarse surface and the fracture along the initial crack surface is found out.