Fatigue Life and Reliability of Satin Woven Glass Cloth FRP under Random Loading

Abstract

An investigation was made on the fatigue properties under random loadings of satin woven glass cloth FRP. Constant displacement fatigue tests were conducted on FRP test specimens with a random loading fatigue test apparatus. The effects of the input signal type of loading wave and the frequency of input signal of loading wave on th fatigue life of FRP were investigated. Moreover, 8-step stress amplitude fatigue test and randomly programmed ones were conducted on the FRP test specimens and their fatigue lives under these conditions were evaluated.
In order to investigate the effect of filler in the resin on the fatigue life, the test was conducted on FRP test specimens containing the filler (CaCo₃) with a rotating bending fatigue test machine.
According to the results of repeated bending fatigue test, a longer fatigue life was obtained at the long life region in the case where sinusoidal wave was used for the loading signal compared with other types of loading waves like pulse and triangle waves.
As for the fatigue life, there was no difference between the FRP test specimens with and without filler. However, the specimens with filler showed a larger scatter of fatigue life with increasing filler content.