Abstract
In general, the mechanical properties of high-polymeric composites depend on testing conditions such as the environmental temperature and the loading velocity. Few studies, however, have been made on the stress rate dependence of GFRP under different temperature environments. In the present paper, tensile tests for glass-mat FRP were made with stress rates ranging from creep tests to fatigue tests with low frequencies at low (-20°C), intermediate (room temperature and 60°C) and high temperatures (100°C) over the heat distortion temperature of the matrix. As a result of statistical data analysis based on two-parameter and three-parameter Wiebull distributions, the tensile strengths of glass-mat FRP were much more affected by the stress rate at high temperatures than at low and intermediate temperatures. The relationship of this fact to the tensile failure modes of the specimens was qualitatively discussed by observing failed specimens and evaluating the parameters involved in the time-dependent stochastic damage model of GFRP proposed by Miki and Fujii.
