Etude statistique par la méthode de weibull de lavariabilité de la résistance à la flexion d'un verre sablé

Abstract

In general, mechanical strength, lifetime, and all other properties related to defect distribution in a brittle material typically exhibit wide dispersion during experimental estimation. Among various statistical methods, we focused on the application of the Weibull method. This model is often used to characterize the variability of mechanical strength in brittle materials, which is closely linked to the distribution of existing defects. Its application requires determining the Weibull modulus mmm and characteristic stress os from experimental data.

In our study, under different test conditions, we varied the sand projection velocity V, sand rain size, and projected mass, with a constant impact angle a-90°. We determined the parameters m and da using linearization methods of the model (both numerical and graphical) from multiple batches of 20 identical samples of flat soda-lime glass. Based on experimental values of mechanical strength ranging from 15 to 54 MPa, estimates of the Weibull modulus m varied between 3.067 and 7.329. Values of do ranged from 22 to 98 MPa. The Weibull plots exhibited a unimodal behavior, suggesting a single statistical family of defects governing mechanical strength. This hypothesis was supported by micrographic observations of samples damaged by sand impacts.