Glass fibers viscoelastic behavior

Creep tendency in glass and carbon fibers is very low, in aramid fibers it is higher. In combination with organic matrices or adhesives, their viscoelastic behavior determines creep tendency in the composite. In comparative relaxation tests up to 1000 h at approx. 50% short-term strength, carbon fiber reinforced plastics indicated virtually no creep, glass fiber reinforced plastics exhibited low creep (approximately twice as much as pre-tensioned steel, while aramid fiber reinforced plastics showed four to five times as much creep [1011]. 

Wen, X., Wang, X., Cai, Z.-Q., Pi, P., Cheng, J., Yang, Z., 2011. Cure kinetics and chemo-rheological behavior of a wind epoxy resin system and its viscoelastic properties reinforced by glass fiber matt with process of vacuum assisted resin transfer molding. High Performance Polymers 23, 477—484. 

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