Statistical Analysis of the Asphalt Mixtures Volumetric Properties

Based on statistics principle, random error and systematic error were considered and the volumetric properties of the two mixtures types, namely A and B, were statistically analyzed using different distribution methods. Seventy-two samples of mixture A and fifty-two of mixture B were fabricated using the Marshall method. The probability distributions were compared on the basis of goodness of fit. Weibull model was found to be most appropriate model for describing the asphalt mixtures volumetric properties distribution. The two-parameter Weibull distribution function applied well to model the bulk specific gravity and voids filled with asphalt data, whereas, the three-parameter Weibull distribution appeared to be more appropriate in the discussing of air voids and voids in mineral aggregate. The experimetal results is revealed that compared with the mean value, the peak value of Weibull distribution was suggested as an alternative and more powerful parameter for describing the test data distribution characteristic. The analysis of test results also revealed that there were significant differences in the volumetric properties of the two tested mixtures for the same confidence level. The confidence interval decreased with the decreasing in reliability.