Accession Number : ADP005997

Title :   Damage Growth in Composite Bolted Joints,

Corporate Author : POLITECNICO DI MILANO (ITALY)

Personal Author(s) : Giavotto, V. ; Caprile, C. ; Sala, G.

Report Date : MAR 1988

Pagination or Media Count : 12

Abstract : Static and fatigue failures of composite joints are dominated by the growth and propagation of typical damages, up to some catastrophic condition. Starting from experimental observations some typical damage propagation patterns are identified and analyzed with simple models and finite element schemes. This extension of the fracture mechanics approach, to a broader class of damages allows some insight into the intricate behavior of FRP joints, and gives some suggestion for interpreting and correlating experimental data. Fatigue and failure of composite materials are still a difficult and intriguing problem, despite the large research effort devoted to them in the last years. This applies even more strongly to bolted joints, where fatigue damage and static failure are likely to occur at lower load levels and with more complicated patterns. These are several different reasons for this fact, the first being the real intricacy of the complex phenomena involved in composite failure, especially at a microscopic level. But definitely, another reason has been the unsuccessful attempt to transfer too literally the Fatigue and Fracture Mechanics approach, that was successful for metals. (SDW)

Descriptors :   *BOLTED JOINTS, *DAMAGE, *FAILURE(MECHANICS), CATASTROPHIC CONDITIONS, COMPOSITE MATERIALS, DAMAGE ASSESSMENT, EXPERIMENTAL DATA, FAILURE, FATIGUE(MECHANICS), FINITE ELEMENT ANALYSIS, FRACTURE(MECHANICS), GROWTH(GENERAL), JOINTS, LOW LEVEL, METALS, MODELS, PROPAGATION, STATICS.

Subject Categories : Couplers, Fasteners, and Joints
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE