![]() ![]() observed that the bending strength and stiffness of bamboo stems are greatly affected by the silica rich epidermal layer, which is attributed to the destruction of the parenchyma near the outer stem wall at the interface between parenchyma cells. ![]() The tensile strength of bamboo decreases with the increase of fiber diameter, and the fatigue life and fatigue limit increase with the decrease of fiber density. The properties of fiber also have a significant impact on the properties of bamboo. Thus, bamboo becomes more ductile as humidity increases. ![]() observed the highest bamboo shear modulus of bamboo at 60% humidity and the highest bamboo shear strength at 60%–80% humidity. The tensile, compressive and flexural strength of bamboo decreased significantly with the increase of humidity. Compared with the outside, bamboo has higher toughness and lower hardness. The average strength of bamboo is similar to that of hardwood. From the inner layer to the outer layer, the strength and stiffness of bamboo gradually increase, and the bamboo with high bamboo stem has higher mechanical properties. In addition section, the compressive strength of upper bamboo section will be higher than that of the bottom, which is caused by more vascular bundles in the upper part of bamboo. The compressive strength of Moso bamboo was calculated as 45–65 N/mm 2. Calculated the knotted and parallel grain tensile strength of moso bamboo as 163.1 MPa, with a non-knotted tensile strength along the grain of 177.9 MPa, and along the grain tensile modulus of elasticity of 11.65 GPa. Bamboo nodes and vascular bundles mainly affect the energy absorption capacity of bamboo, and the energy absorption capacity of the nodes is greater than that of internodes. ![]() , the high strength of moso bamboo is due to the vascular bundle fibers that can withstand high stress during deformation. Moisture content has a significant effect on the mechanical properties of bamboo, and bamboo with high moisture content has higher fracture energy. Bamboo fracture is characterized by three forms: matrix failure, interface dissociation and fiber fracture. īamboo exhibits better mechanical properties than ordinary wood and has excellent compression and bending resistance. However, the radial and tangential mechanical properties of bamboo have rarely been explored. Hence, the tangential tensile strength and the TTMOE play vital roles in moso bamboo cracking.Įxtensive research has been conducted to analyze the longitudinal tensile strength, compressive strength, flexural strength, stiffness, and elastic modulus of bamboo along the fiber direction. Once the raw bamboo is cracked, it will cause the bamboo to rot, which and reduces its strength.īamboo loses water due to the equilibrium moisture content of the external environment and consequently, shrinks and deforms therefore, cracks will easily occur in raw bamboo when the tensile stresses on its inner and outer surfaces exceed the tangential tensile strength. Using raw bamboo in construction projects can reduce the energy consumption of bamboo processing however, moso bamboo can easily crack during storage, transportation, and after felling. Large-diameter moso bamboo ( Phyllostachys edulis) tubes are used as the main force-bearing members in construction projects for forming engineering raw bamboo, while small-diameter moso bamboo and its branches are used in fiberboard manufacturing. Keywords: Engineering raw bamboo moso bamboo tangential tensile strength tangential tensile modulus of elasticity bamboo cracking Hence, this study provides a theoretical basis for future research on bamboo cracking. When the moisture content was 15%, the tangential tensile strengths of the inner, middle, outer, culm wall, bamboo node, and diaphragm samples of the five-year-old moso bamboo were 3.17, 3.29, 3.31, 3.24, 3.67, and 8.85 MPa, respectively. Below the fiber saturation point, the tangential tensile strength and TTMOE values of the bamboo gradually decreased with increasing moisture content. The tangential tensile strength and the tangential tensile modulus of elasticity (TTMOE) followed: outer > middle > inner, and diaphragm > bamboo node > culm wall. Formulas for calculating the tangential tensile strength of moso bamboo and adjusting the moisture content were also determined. We found that the tangential mechanical properties of the culm wall were mainly dependent on the mechanical properties of the basic structure of the thin wall. Abstract: In this work, we used tensile tests to analyze the tangential failure forms of raw bamboo and determine a relationship between tangential tensile strength, elastic modulus, position, density, and moisture content. ![]()
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