This study conduct a mode III fracture toughness measurement test on a sandstone specimen with an edge crack in an anti-plane

shear-loading situation and obtain the mode III fracture toughness by using derived theoretical formulas. The testing conditions do not include confining pressure

and the mode III fracture test is conducted under a uniaxial load application. In addition

the study used a change in specimen properties

caused by exposure to high temperature

as a variable condition for further discussion. The research results show that the proposed method of performing the mode III fracture toughness test is reliable and stable. Heating at temperatures up to 200 ℃ enhance the sandstone specimen’s mode III fracture toughness. The toughness decline after 200 ℃ and then leveled off after reaching 600 ℃. The uniaxial compressive strength

dynamic Young’s modulus

dynamic Poisson’s ratio

and mode III fracture toughness show a declining trend following an increase in sintering temperature. The specimen appeared to be molten

and evident micro cracks appear on the surface.