Resumo (PT):
Abstract (EN):
The use of fiber-reinforced polymers in civil construction applications has produced structures with a high specific stiffness and strength. Although these materials exhibit good mechanical performance, their strength and stiffness may degrade significantly over time. The major contributions come from the viscoelastic behavior of the matrix, cumulative damage and damage propagation within the matrix, and fiber breaking. One serious consequence, even under static fatigue (constant loading), is that creep rupture may occur in a catastrophic manner. This is critical in civil engineering applications, since the structural components are expected to operate for 50 years (or more) at safe conditions. The lack of full understanding of the fundamental parameters controlling long-term material performance necessarily leads to overdesign and, furthermore, inhibits greater utilization. In this respect, lifetime prediction of these components must be tackled before wider dissemination of civil engineering applications can take place. This chapter reviews some theoretical approaches to long-term failure criteria and accelerated characterization experiments concerning long-term failure behavior. Time-dependent failure criteria are presented and developed for practical applications.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
33