2025 Volume 60 Issue 3 Pages 149-162
In this study, the strength improvement of adhesive joint is discussed for the steel/epoxy butt joints due to the duplicated interaction of additional notches. The experiment is conducted by varying the adhesive layer thickness h and the notch depth t in the range h =0.1~2.0mm and t =0.4~1.7mm when the specimen diameter D =12.7mm and the interval between the notch and the interface c =1.0mm. The intensity of the singular stress field (ISSF) at the interface end is analyzed by the proportional method, as well as the interface stress distribution. The results show that the adhesive strength can be expressed as a constant ISSF independent of h and t except for too deep notch. The adhesive strength σcJIS (h) of the butt joint measured by following JIS (Japan Industrial Standard) without notch increases with decreasing h due to the interaction of upper and lower adhesive bondlines. The adhesive strength for the case of additional notches increases with increasing t due to the duplicated interaction. The analytical and experimental results showed that the adhesive strength can be improved due to the duplicated interaction of suitable additional notch.
