Novel Design of Composite Joints

Adhesively bonded joints have been applied widely in
many industries especially with composite materials.
Because of the unavoidable geometric change,
discontinuity or material change, the joints or the
joint areas are potentially the weakest regions in
structures. Thus the design of the structural joints
is very critical for the whole structure and must be
very carefully designed. In this book, two new
designs were introduced to improve the performance of
the double-strap joint. For the first design, thin
step composite laminate attachments were designed and
attached onto the conventional double-strap joints.
For the second one, multiple layers of straight
attachments were used instead of one single layer. In
both new designs, additional load transfer paths were
created and localized interfacial stress
concentrations at the leading joint edge of the joint
were reduced. Experiments were performed and the
results revealed that both of the new designs had
significantly greater strengths than the conventional
double-strap joint. Interfacial stresses along the
bondlines were analyzed in order to understand the
increase in joint strength and the change of failure
modes in the joints.

Autorentext

Haiyang Qian was born in Suzhou, China, 1978. In January 2002, hejoined the School of Aeronautics and Astronautics, PurdueUniversity (USA) as a graduate student working with Prof.Chin-Teh Sun. He received his Ph.D. degree in May 2008. Hisresearch is focused on Fracture Mechanics, design and damagetolerance of composite material structures.

Klappentext

Adhesively bonded joints have been applied widely inmany industries especially with composite materials. Because of the unavoidable geometric change,discontinuity or material change, the joints or thejoint areas are potentially the weakest regions instructures. Thus the design of the structural jointsis very critical for the whole structure and must bevery carefully designed. In this book, two newdesigns were introduced to improve the performance ofthe double-strap joint. For the first design, thinstep composite laminate attachments were designed andattached onto the conventional double-strap joints.For the second one, multiple layers of straightattachments were used instead of one single layer. Inboth new designs, additional load transfer paths werecreated and localized interfacial stressconcentrations at the leading joint edge of the jointwere reduced. Experiments were performed and theresults revealed that both of the new designs hadsignificantly greater strengths than the conventionaldouble-strap joint. Interfacial stresses along thebondlines were analyzed in order to understand theincrease in joint strength and the change of failuremodes in the joints.