正負繰り返し履歴破壊とせん断破壊の破壊メカニズムの相違の検証

抄録

In the previous paper, “Reversed cyclic loading failure” was proposed. Under reversed cyclic loading, shear resistance mechanism repeats temporary disappearance and rebuilding. This failure occurs when shear resistance mechanism is not rebuilt after the temporary disappearance. The temporary disappearance occurs because of the opening and closing of cracks under reversed loading. And this means the proposed failure mode is peculiar to reversed cyclic loading. The impossibility of rebuilding after the temporary disappearance is considered to be affected by the stiffness deterioration of cracked concrete due to reversed cyclic loading. Therefore, the occurrence of this failure mode is estimated not to be defined by the maximum value of shear load but to be defined by some index which is connected with the stiffness deterioration of cracked concrete.
This failure mode has been considered to be a kind of shear failure because of the shear deformation increase when it occurs. The purpose of this paper is to clarify the difference of failure mechanism between “Reversed cyclic loading failure” and “Shear failure”. For this purpose, shear bending cyclic tests were carried out, in which the deformation behaviors of beams which were failed by shear failure or reversed cyclic loading failure were measured in detail. On the basis of the comparison of the deformation behaviors, the difference of failure mechanisms was confirmed.