Premium
STRESS‐STRAIN AND FAILURE CHARACTERISTICS OF POTATO TISSUE UNDER CYCLIC LOADING
Author(s) -
PITT R. E.
Publication year - 1984
Publication title -
journal of texture studies
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.593
H-Index - 54
eISSN - 1745-4603
pISSN - 0022-4901
DOI - 10.1111/j.1745-4603.1984.tb00374.x
Subject(s) - materials science , plasticity , composite material , hysteresis , stress (linguistics) , shear stress , softening , strain (injury) , shear (geology) , anatomy , medicine , linguistics , philosophy , physics , quantum mechanics
Cyclic compressive loadings between zero and a fixed peak stress were applied to cylindrical samples of potato flesh. The tissue can eventually fail under stress magnitudes insufficient to cause failure initially. Failure was apparently due to shear rupture, as under ordinary constant‐strain‐rate loading to failure. An empirical model for the probability distribution for the number of cycles to failure indicates that the likelihood of failure on successive load cycles remains approximately constant with the number of cycles applied. Thus, failure is apparently a random process and not an accumulative one. Normal strain at failure is significantly greater under cyclic loading. It is theorized that failure is due to a random degradation in the shear strength of the tissue. Stress‐strain characteristics under cyclic loading are marked by an accumulation of plastic deformation in the first few load cycles, loss of firmness and a hysteresis between loading and unloading. An earlier model for the parenchyma cell is extended to include plasticity in the cell wall in the initial distension. This plasticity is predicted to contribute to the apparent tissue plasticity and loss of turgor pressure in the first load cycle.