Analytical Solution for Externally Bonded Joints Considering Snap-Back

Abstract

Studying interfacial behavior is important for a composite structure involving relative movement or slip at its joint interface. Recent experimental and theoretical studies on bond interfaces have found that snap-back phenomenon may occur, in certain scenarios, in monotonic pull-off tests where interfacial slip in some local region is opposite to that in other areas. Little is known about the snap-back phenomenon at present, such as the conditions under which it occurs, distribution and development of reverse slip fields, and whether and how it affects global load-deformation responses. Further and more in depth investigations into the snap-back problem are necessary for better understanding of joint interfaces; e.g., in experimental bond tests with digital image correlation (DIC) technology where detailed interfacial movements on a whole bond interface are recorded for identification of interfacial properties. Therefore, this work attempts to study the snap-back problem in detail through analytical study. Furthermore, the results from this work provide a theoretical explanation of an interesting interfacial phenomenon—strain softening toward the loaded end that has puzzled researchers in the past. This paper facilitates a better understanding of the interfacial behavior for composite structures.