The Mechanical Properties of Caladium Petiole

In this study, the mechanical properties of Caladium (Caladium × hortulanun Birdsey) petiole were investigated. The petiole was considered as a composite beam which consists of rind and core parts. To classify the mechanical properties of rind and core part of petioles, two-phase three-point bending tests were conducted on the specimens cut from petioles. Linear beam theory was used to convert the time-dependent bending forces, during the three-point bending tests, to relaxation moduli. The result shows that the mechanical properties of rind and core parts of Caladium are very different. The relaxation modulus of rind is approximate 40 times higher than relaxation modulus of core at time = 600 s after applying bending load, and the relaxation time distribution of core is wider than the relaxation time distribution of core. The three- and seven-parameter linear viscoelastic constitutive models were used to describe the time-dependent relaxation moduli of rind and core of caladium petiole. The fitted results show that the seven-parameter Wiechert model can describe the viscoelastic behaviour of Caladium petiole very well. The finite element analysis was used to assess the error of this test methodology. The reaction force error because of the tapered diameter of specimens is about 12%.