Cross-species bamboo grading based on flexural properties

Abstract

This experiment studied five species of bamboo culms [e.g. B. vulgaris (ampel), D. asper (betung), G. apus (tali), G. atroviolacea (hitam), and G. pseudoarundinaceae (andong)], then analyzed the possibility to develop cross-species bamboo structural grading (both strength and capacity grading) models by mean of dummy variable regression. Since the regression analysis resulted the significantly different coefficient values of the dummy variables, any coincided trendline did not found, but some parallel ones were obtained. The non-coincided but parallel trendlines indicated that a linear equation can estimate the average value of the grade determining property (GDP) of cross-species bamboo structural grading, while the constants must be added to consider the species influence. Meanwhile the non-parallel trendlines indicated that the different linear equation must be applied for every bamboo species. The crossspecies bamboo structural grading could not reliably justify in this study. Species have a strong influence on bamboo grading. Therefore, the authors suggest considering the species identification in the bamboo structural grading.