Anatomy and strength properties between tropical bamboo Gigantochloa levis AND G. scortechinii

The relationship between anatomy, physical and strength properties of tropical bamboo species Gigantochloa levis and G. scotechinii were investigated. The culms of these bamboo of age-group 3 were selected, harvested and processed for use in the studies. Each species has different in fiber characteristics. The morphology of the fibers showed significant differences between species in terms of length, diameter and lumen size. The fibre length ranged between (1745.27-2039.98 μm), diameter (17.26-22.75 μm), lumen (3.83- 8.66 μm) and wall thickness (1.35-5.31μm). The vascular bundle ranged between 4-7/4 mm2 and is dense at the outer position having 8.5 vascular bundle/4mm2, middle position 4.88 vascular bundle/4mm2 and the inner position 3.4 vascular bundle per/4mm2. The vascular bundle length ranged between 845 - 1183 μm and width of 530-759 μm. The moisture content (MC) ranged between 73 -112%. The MC is higher at the internodes with 95% compared with the nodes the 78%. The inner layer of bamboo has MC of 126%, middle layer 83% and outer layer 41%. The density increases from inner to the outer layer of bamboo. It starts from 500 kg / m 2 at inner and increased to more than 820 kg/m2 at outer part of bamboo at 12% MC. The specific gravity (SG) ranged between 0.69-0.78, where the inner position having SG of 0.58, middle 0.73 and outer positions 0.94. The shrinkage in the radial, tangential and the volume between (5-9, 7-12, 10-17%) respectively for both species. Higher rate of shrinkage was noted at the inner position (8.60, 13.50, 15.44%), follow by the middle (6.85, 9.72, 12.57%) and outer (5.04, 6.52, 10.40%) respectively. The tensile strength ranged between 103.38-122.15 MPa. The tensile strength of dried bamboo is 138.87 MPa compared with 89.95 MPa for green bamboo. The tensile of modulus ranged between 2661.65-3793.13 MPa. Mean average Tensile Modulus of air dried bamboo was 4003.85 MPa compared to 2786.96 MPa for green bamboo. The shear strength is around 5.22-8.87 MPa. The shear of dried bamboo were 8.20 MPa compared with 5.76 MPa for green bamboo