抄録
The failure characteristics such as strength and toughness of various types of concretes including steel fiber reinforced concrete and light weight concrete, were investigated in order to contribute to the establishment of evaluating methods of the characteristics. The following results were obtained. The shear strength measured from the direct a double shear tests was proportional to the tensile strength. The absorbed energy ratio Wcq/Wcp in compression was found to be a useful parameter to indicate the failure behaviour of concrete, that is, how suddenly concrete loses its load carrying capacity after the maximum loads reached. Wcp indicates the absorbed energy of a specimen up to the point of maximum load Pmax, and Wcq the one up to the failure point, where the load descends to 1/3 of Pmax. The ratio Wcq/Wcp was well related to the brittleness index, which is the ratio of compressive strength σc to tensile strength σt. The effect of steel fiber reinforcement on the improvement of concrete toughness was greater in flexure than in compression.
