The influence of heat on shrinkage and water absorption of Dendrocalamus giganteus bamboo as a functionally graded material

The main objective is to present the results of an investigation on the effect of heat and time exposure on hygroscopic property of Dendrocalamus giganteus bamboo. The shrinkage and water absorption of bamboo segments in longitudinal, radial and tangential directions, due to heat effect of seven different temperatures from ambient to 225 °C during 3 h and 24 h has been investigated. An equation based on the principal of curve fitting has been established for rapid, transition and slow phases of water absorption. The non-uniform shrinkage and water absorption tests in tangential direction at different temperatures during 3 h carried out to obtain the fiber and matrix shrinkage and water absorption separately. The water absorption test result shows that by increasing the temperature and time exposure the hygroscopic property of bamboo is reduced. Subjecting to heat at higher temperatures can slow down the rate of water absorption in short term.