Porosity estimation of Phyllostachys edulis (Moso bamboo) by computed tomography and backscattered electron imaging

摘要

This study aims to investigate and quantify the porosity in the crossudsection of Phyllostachys edulis (Moso bamboo) culm wall. The porosity results areudexpected to be utilised in numerical study of heat and moisture transfer. Computedudtomography (CT) and backscattered electron (BSE) imaging methods are utilised inudthis study because these two methods allow measurements of the anisotropic featuresudof bamboo specimens. The results of these two methods can be represented asudthe function of the real dimension rather than the pore size distribution of theudspecimen. The specimens are obtained from eight different locations along theudMoso bamboo culms. Both internodes and nodes specimens are measured in thisudstudy. The average porosity, standard deviation (SD) and coefficient of variationud(COV) are calculated for BSE and CT results. Pearson product-moment correlationudcoefficient (PPMCC) is also calculated in this study to analyse the correlationudbetween the BSE results and CT results. Typical porosity results from 400 samplingudpoints and 10 portions average porosity are analysed in this study. The CT scanningudresults show similar trend with BSE results. The correlation relationship betweenudBSE and CT results approaches moderate correlation level to strong correlationudlevel. The average porosity of internode specimens is from 43.9 to 58.8 % by BSEudmeasurement and from 44.9 to 63.4 % by CT measurement. The average porosity ofudnode specimens is from 37.4 to 56.6 % by BSE measurement and from 32.1 toud62.2 % by CT measurement.ud