Schjelderup, H. C.
Director, McDonnell Douglas Corp., Long Beach, Calif.
Jones, B. H.
Senior engineer/ecientiet, McDonnell Douglas Corp., Long Beach, Calif.
Pages: 22 Published: Jan 1969
Practical design problems which have become evident as a result of current DOD-industry composite development programs are discussed. Design problems related to residual stresses beween matrix and filaments are reviewed, and the significance of thermal effects on the interface between filament and matrix is out-lined. Local failure and strength properties, as influenced by filament diameter, and the ever-present problem of interlaminar shear are studied. The concept of balanced and minimum gage laminates is considered together with its interaction with design. The influence of design criteria, allowables, and joints on composite structures design is discussed. Detail design problems related to thermoelasticity and fatigue highlight some of the potential design problems which are unique to composites. As experience in the design of composite structures is gained, many requirements for the future evolve. The requirements are basically a need for uniformity of practice in order for composites to become cost competitive with conventional materials. Suggestions and recommendations for future standards in composite design are presented.
composite materials, fiber composites, reinforced plastics, joints (junctions), aircraft structure, design, stress, tests, evolution
Paper ID: STP49823S