Purnell proposed more complex understanding about ageing of GRC, offering glass static fatigue as the main reason (Purnell, 2001).
This phenomenon is called static fatigue in glass technology literature and is described as constant breaking of Si[O.sub.2] bonds at the tips of pre-existing flaws due to static load (Figure 3).
This results to initial defects on the filaments and further static fatigue process, described previously.
The main reason for strength loss is flaw growth on the surface of glass filaments, a process called static fatigue, which is not yet fully understood by scientists.
The aim of the study consists in analyzing and comparing material behavior under cyclic and static fatigue loadings, at the same temperature and under air, to determine the effects of a cyclic loading on damage and lifetime.
For static fatigue tests, specimens were first loaded at constant loading rate of 1kN/min, and periodically (every 6 or 12 hours) unloading-reloading cycles were carried out in order to determine the secant elastic modulus.
1), a greater proportion of recorded signals and a more significant release of energy were obtained at a given time than under static fatigue for the same values of temperature and maximum load.
Yao  divided the structural fatigue into two kinds of problems: static fatigue
and vibration fatigue.
Aiming to improve technical safety in traffic and other fields, this book examines the time-dependent mechanical properties of solids like metallic alloys and silicate glasses, focusing on the relaxation of mechanical stresses, density relaxation, internal friction, static fatigue
, and the reduction of strength caused by a cyclic loading.
of Static peak joint length length staples specimens load (avg) (in.) (Kip) 1 -2 3 4 5 6 Stapled 6 1.5 20 9 0.86 (8.1) (b) 8 1.5 20 9 1.01 (5.3) 10 1.5 20 9 1.04 (4.7) Glued 6 1 8 9 0.92 (6.9) 8 1 8 9 1.15 (8.7) 10 1 8 9 1.28 (11.2) Static Fatigue
Type of Gusset-plate moment joint length (avg) Passed moment Failed moment (in.) (Kip-in.) 1 -2 7 8 9 Stapled 6 12.1 6.77 A (c) (8) 7.82 A (7) 8 14.1 6.42 A (5) 7.47 A (5) 10 14.5 7.23 A, B (5) 8.28 A, B (4) Glued 6 12.9 7.82 B (10) 8.87 B (9) 8 16.1 9.10 C (12) 10.2 C (10) 10 17.9 8.98 C (8) 10.0 C (8) Fatigue Ratio of static/fatigue Type of Gusset-plate Cumulative no.
He states that [it] not only will eliminate the problems of hydrostatic blood pooling (swelling) in the lower limbs but also provide the necessary exercise to keep the tissues around the sitting area plastic, thereby reducing the problem of static fatigue
this mandates a high level of design reliability.Stress-rupture (or static fatigue
) is a sudden failure mode of the composite overwrap that can occur at normal operating pressures and temperatures i.E.