Visco-elastic-plastic model to represent the compression behaviour of sugarcane agricultural residue

The objective was to develop a visco-elastic-plastic model for the prediction and characterisation of the compaction behaviour of sugarcane agricultural residues during the production of bales under different moisture contents (27%, 37% and 48%) and different particle sizes (similar to 300 mm, 150 mm and 80 mm). Data of confined-compaction and stress relaxation experiments were used to calibrate the model parameters. The proposed constitutive equation was composed of a generalised Maxwell model with three branches in series with a plastic component. The procedure was developed to characterise model parameters and used a numeric approach to calculate the hereditary integral when fitting the experimental curves, whilst the stress due to the plastic strains was fitted with a polynomial. The model provided good accuracy (R-2 > 0.92) to fit the compaction and relaxation stages with the same set of parameters. Thus, it predicted the energy required to produce bales as well as the final relaxed density of this sustainable material that may become an important source of energy. (C) 2021 IAgrE. Published by Elsevier Ltd. All rights reserved.

Automated summary

The study aimed to develop a model for predicting and characterizing the compaction behavior of sugarcane agricultural residues under different moisture contents and particle sizes. The model was calibrated using confined-compaction and stress relaxation experiments, providing accurate predictions of the energy required for bale production and the final relaxed density of the material.