Time-dependent strength of optical fibers

The results of strength investigations of optical fibers with two-layers coat in dynamic fatigue measurements have been presented in this paper. Strength was measured at three strain rates in ambient air and aqueous solution. The results obtained were worked out using a stress-corrosion model, for which fracture mechanics laws were applied. An increase in relative humidity leads to an acceleration of flaw growth. Predicted strength of optical fibre, based on a dynamic fatigue test, agrees with static fatigue measurements.