Flexural fatigue life analysis of unsaturated polyester-methyl methacrylate polymer concrete

Laboratory and statistical evaluations were performed to examine the flexural fatigue performance of unsaturated polyester-methyl methacrylate (UP-MMA) polymer concrete. Target stress levels were 0.9, 0.8, 0.7, and 0.6 with a fixed stress ratio of 0.1. A 5 Hz sinusoidal load with a constant-amplitude frequency was applied to a prismatic specimen (100 × 100 × 400 mm) using a 250-kN universal testing machine (UTM). MMA contents considered were 0, 10, 20, and 30 wt.%. In addition, the two-parameter Weibull distribution was employed to analyze the fatigue life probability distributions of UP-MMA polymer concrete. Three different analysis methods-the graphical method, method of moment, and method of maximum likelihood estimation-were applied to estimate the distribution parameters of the two-parameter Weibull distribution. The results have shown that the two-parameter Weibull distribution describes the fatigue life probability distributions of UP-MMA polymer concrete with quite high statistical correlation coefficients. Also, the goodness-of-the-fit of the fatigue life data obtained was verified by means of the Kolmogorov-Smirnov test, which were all accepted at a 5% significance level. Finally, a single-log fatigue equation was derived to predict the fatigue life of UP-MMA polymer concrete.