FATIGUE STRENGTH OF FIRE REINFORCED PLASTIC MATERIAL

Abstract

The fatigue strength of 0/90°woven based glass reinforced plastic (GRP) material has been investigated. Axial fatigue tests were carried out on plain specimens for 0, 0.5 and -0.1 stress ratios and on notched specimens for zero stress ratio. Notched and unnotched tensile properties were also investigated. The results show, the fatigue life at the same maximum stress level increases with the increase in stress ratio. Presence of notch decreases the tensile strength and the fatigue strength of GRP. The fatigue stress concentration factor decreases slightly with the increase in the number of cycles to failure. as opposed to the fatigue behaviour of metals. The tensile strength of the GRF has also been to be notch sensitive