New Model for Elastic Behaviour of Cellular Material

The force to deform cellular material can be described as a function of the deformation expanded in a Taylorʹs series. The resultant three-term cubic model is used to identify the three characteristic sections of the force-deformation curve related to the expected cellular response. The elastic, viscous and failure actions in the cellular material, which are all present from initial application of force to final rupture, are discussed in relationship to the first, second and third terms of the model, respectively. In addition, the model permits the definite identification of an inflection point and a theoretical failure point for the expected sigmoidal curve. The model was shown to be applicable to cellular force-deformation curves, from both plant and animal tissues, even when there was deviation from the expected sigmoidal curve shape. There was also an indication of how such deviation might describe the specimen and the test. The model was tested with data from both compression and tension tests with several materials from various origins and found to fit all data with a consistently high value for the coefficient of determination.