ＧＦＲＰ円筒接着継手の組合せ曲げねじり荷重下における破壊挙動（接着不良の影響）

Abstract

In the present study the effect of a flawed part in the cylindrical adhesive-bonded joint of glass-fiber reinforced plastics on its mechanical property and the process to failure were investigated under combined bending and torsional loading conditions. Loading tests were performed in bending, torsional and combinded loading conditions in which the proportion of bending to torsional moment was set to 1:1 and 1:2. Both the area and the location of the flawed part of specimen were changed in two varieties. From the experimental results the followings became clear.(1) Even though two adhesive-bonded joints had the same area of the flawed part, the mechanical properties were quite different when the flawed parts were at different locations.(2) In the bending condition, the flaw reduced the stiffness of the specimen but affected the strength little.(3) Under the combined loading condition in which the proportion of torsional to bending moment was whithin a certain limit, the strength reduction ratio was higher than that in bending tests. However, in the condition of higher proportion of torsional moment the strength reduction ratio was lower than that in bending tests. The proportion of torsional moment at which the strength reduction ratio changed from that in bending tests to that in torsional tests increased with the area of the flawed part.