AbstractThis thesis presents the results from 286 four-point bending tests carried out on dry Guadua angustifolia Kunth culms for which a number of mechanical and physical properties were measured and documented. The aim of this thesis is to demonstrate that relationships can be established between destructively and non-destructively measured properties and based on these relationships, to evidence that a grading system for bamboo is possible. The significance of this is that graded bamboo would enable designers to use the material safely and economically in construction.
Correlations between flexural strength (fm,0), static modulus of elasticity (Em,s), dynamic modulus of elasticity from stress-waves (Ed) and density (ρ) provided mediocre results with R2 ranging from 0.34 to 0.56. However, properties such as flexural stiffness (EIm,s), flexural capacity (Mmax) and mass per unit length (qtest) which are less dependent on geometric properties, provided much stronger correlations with R2 ranging from 0.85 to 0.94. Based on these findings, it is suggested that instead of using a stressbased approach for bamboo design, we should employ a capacity-based approach as is often used with engineered timber products.
The analysis showed that mass per unit length, average external diameter and flexural stiffness were well correlated with flexural capacity and it is therefore proposed that these parameters could be used as Indicating Properties (IPs), either separately or in combination, for flexural capacity in a grading procedure for dry full-culm bamboo as presented at the end of this thesis.
|Date of Award||2016|
|Supervisor||David Trujillo (Supervisor)|