Tensile characterisation of bamboo strips for potential use in reinforced concrete members: experimental and numerical study

Abstract

The usage of bamboo as a replacement for steel reinforcement in concrete is in the early stages of development as bamboo reinforced concrete (BRC) members involve a lot more uncertainties than steel-reinforced concrete members. The properties of bamboo vary inter- and intra-species. A prerequisite to developing a rational design of BRC members, therefore, requires two stages—(i) a statistical characterisation of the mechanical properties of bamboo, and (ii) identifying the variables contributing significantly towards the stress-strain/load-displacement behaviour. This paper first experimentally characterizes the longitudinal tensile properties of Bambusa balcoa, a commonly found bamboo species in India. Statistical analysis of the experimental results suggests that most of the mechanical properties follow a lognormal distribution. The elastic modulus is found to have a dominant contribution towards the stress-strain behaviour. A high fidelity finite element model, the results of which are validated with experiments, indicates that only the variation of elastic modulus can capture 92% of the variability in the experimental results. We also create a low-fidelity finite element model using equivalent tensile modulus, which can capture 82% of the variability in the experimental results. Lastly, a finite element model of a BRC beam is created using the low-fidelity finite element model of bamboo. A comparison with the experimental results suggests a good agreement between them.