Exploring the New Applications of Structural Bamboo
Exploring the new applications of structural bamboo
Introduction
Bamboo is versatile group of grass, belonging to the subfamily Bambusoideae of the family Poaceae in Asia. It is fast growing, highest yield, low cost, and a renewable natural resource with excellent mechanical properties. To explore its potential as a building and structural material, further research on its properties is needed. In the following, the structure and mechanical properties of bamboo will be introduced. Then, a comparison of the mechanical properties between bamboo and other materials will be made. Previous literature on structural bamboo will be reviewed. In addition, practical considerations in construction uses, defects and protective treatments, and applications of bamboo will be described. Finally, the future development of structural bamboo and the objectives of this study will be stated.
Structure of bamboo
Macrostructure: Bamboo culms are tapered and hollow in shape. The diameter of culm and the internode length vary along the culm. The wall thickness decreases from bottom to up.
Microstructure: Bamboo culm is made up of parenchyma cells and vascular bundles consisted of thick-walled fibers and vessels, similar to fiber-reinforced-matrix composite material. Bamboo fibers are parallel to the axis of internode culm, and more concentrated at the upper part of culm and towards the outer layer of the cross section of wall-thickness. As a result, bamboo possesses the optimum capacity for load bearing.
Mechanical properties of bamboo
The mechanical properties of culm depend on the bamboo fiber distribution and orientation, since the fibers are mainly responsible for bearing loads. (i) Orientation
The mechanical properties parallel to the axis of culm with fibers longitudinally oriented are superior to those in other direction. For example, the elasticity modulus E in the tangential direction is about one-eighth of the E in the longitudinal direction (Villalobos,
Introduction
Bamboo is versatile group of grass, belonging to the subfamily Bambusoideae of the family Poaceae in Asia. It is fast growing, highest yield, low cost, and a renewable natural resource with excellent mechanical properties. To explore its potential as a building and structural material, further research on its properties is needed. In the following, the structure and mechanical properties of bamboo will be introduced. Then, a comparison of the mechanical properties between bamboo and other materials will be made. Previous literature on structural bamboo will be reviewed. In addition, practical considerations in construction uses, defects and protective treatments, and applications of bamboo will be described. Finally, the future development of structural bamboo and the objectives of this study will be stated.
Structure of bamboo
Macrostructure: Bamboo culms are tapered and hollow in shape. The diameter of culm and the internode length vary along the culm. The wall thickness decreases from bottom to up.
Microstructure: Bamboo culm is made up of parenchyma cells and vascular bundles consisted of thick-walled fibers and vessels, similar to fiber-reinforced-matrix composite material. Bamboo fibers are parallel to the axis of internode culm, and more concentrated at the upper part of culm and towards the outer layer of the cross section of wall-thickness. As a result, bamboo possesses the optimum capacity for load bearing.
Mechanical properties of bamboo
The mechanical properties of culm depend on the bamboo fiber distribution and orientation, since the fibers are mainly responsible for bearing loads. (i) Orientation
The mechanical properties parallel to the axis of culm with fibers longitudinally oriented are superior to those in other direction. For example, the elasticity modulus E in the tangential direction is about one-eighth of the E in the longitudinal direction (Villalobos,
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