Análise da resistência mecânica de vigas de mármore sintético através da teoria estatística de Weibull

Abstract

In the present study, the Weibull statistical analysis was adopted for evaluating the flexural strength, as well as its repeatability, of cultured marbles, both pure and reinforced with fiberglass. The objective of this study was to observe the behavior of the Weibull modulus and mechanical strength, as chopped fiberglass was incorporated in the composition of cultured marble. For this purpose, four different compositions with different amounts of glass fiber, by weight, were evaluated, to establish a standard curve of the mechanical behavior of the composite fiber. The Weibull approach enables this analysis since, in addition to the dimensional thickness resemblance of test samples with the products made of synthetic marble, it quantifies the occurrence of imperfections due to the manufacturing process. The results showed that the glass fiber insertion into a mass of 3 kg of synthetic marble, in proportions of 12.5 to 100 grams, caused a variation in the intrinsic resistance, depending on the amount of fiber inserted, which initially fell (0 to25 g) and then increased to a maximum of 100 grams. Another important result was the time of demolding, which strongly influenced the dispersion of the results that, when reduced by 2h to 24h, caused a decrease in Weibull modulus (i.e. increase in the variation of the rupture stress), up to 60%.