Modified Weibull Distribution for Analyzing the Tensile Strength of Bamboo Fibers

Abstract

Abstract:There is growing evidence that the standard Weibull strength distribution is not always accurate for the description of variability in tensile strength and its dependence on the gauge size of brittle fibers. In this work, a modified Weibull model by incorporating the diameter variation of bamboo fiber is proposed to investigate the effect of fiber length and diameter on the tensile strength. Fiber strengths are obtained for lengths ranging from 20 to 60 mm and diameters ranging from 196.6 to 584.3 μm through tensile tests. It is shown that as the within-fiber diameter variation increases, the fracture strength of the bamboo fiber decreases. In addition, the accuracy of using weak-link scaling predictions based on the standard and modified Weibull distribution are assessed, which indicates that the use of the modified distribution provides better correlation with the experimental data than the standard model. The result highlights the accuracy of the modified Weibull model for characterizing the strength and predicting the size dependence of bamboo fiber.

Modified Weibull analysis on banana fiber strength prediction

“…This claim is substantiated Mukhopadhyay et al [17]. Likewise, for oil palm fiber [10], jute fiber [14,15], and bamboo fiber [11,12,18], the fiber cross-sections were approximated to be circular in shape.…”

“…This is evident in Figure 5, 10 mm gauge length plots. Wang et al [11] reported similarly for bamboo fibers and stated the cause to be experimental uncertainties. However, the scale parameter, which denotes the characteristic strength, follows the gauge length effect wherein it reduces as the gauge length increases.…”

“…The higher the Weibull modulus the lower the variability in the strength and vice versa [1], moreover Wang et al [11] stated the Weibull modulus, m of natural fiber are generally falls in the range of 1 to 6. The results in Table 3 fall within this range, likewise does jute [14], and oil palm fiber [10].…”

“…This analysis has been conducted on oil palm fiber by Sia et al [10], bamboo fiber by Wang et al [11,12] , palm leaf sheath fiber by Guo et al [13], wool fiber by Zhang et al [9], and jute fiber by Xia et al [14] and Torres et al [15]. However, no related work on strength prediction of banana fibers has been done by considering the variation of within fiber diameter variation.…”

The effect of elementary fibre variability on bamboo fibre strength

“…This could be explained by the negligible bundle effect in this diameter range. However, many reports claim that there is a diameter dependence of strength and moduli in fibres [26][27][28]. It is important to investigate the diameter influence on the fracture strength, which enables to effectively evaluate its mechanical behaviour.…”