Fracture toughness of coal under quasi-static and impact loading

The fracture toughness of specimens of Canadian coal, expressed as kq, was determined under both quasi-static and dynamic loading conditions. In all tests, a wedge loaded compact tension (WLCT) specimen was used. The quasi-static tests were carried out in a servohydraulic testing machine while in the dynamic testing, a Split Hopkinson Bar was used. Also studied was the effect of orientation of the crack with respect to the coal seam. Loading …