applied sciences
Article A New Technique for Determining the Shape of a Paper Sample in In-Plane Compression Test Using Image Sequence Analysis Paweł Pełczyn´ ski 1, * , Włodzimierz Szewczyk 1 , Maria Bien´ kowska 1 and Zbigniew Kołakowski 2
1 Centre of Papermaking and Printing, Lodz University of Technology, W ó lczan´ ska 221, 95-003 Ł ó dz´, Poland 2 Department of Strength of Materials, Lodz University of Technology, Stefanowskiego 1/15, 90-537Ł ó dz´, Poland * Correspondence: pawel.pelczynski@p.lodz.pl; Tel.: +48-426313816 Abstract: The article presents a new technique for analyzing phenomena occurring during the measurement of the strength properties of paper in the conditions of compression of the tested samples with forces acting in the paper plane. The technique is based on collecting data on the current distance of the clamps holding the tested sample and the force exerted on the sample using a universal testing machine and on the simultaneous recording of image sequence of the sample during the measurement. Next, the resulting images are subjected to processing and analysis, the purpose of which is to extract information about the shape of the sample edge in all phases of the measurement. Its advantage is the ability to determine the deflection arrow of the sample and describe its shape using the selected function given by the analytical parametric formula. It will be helpful in further research on the development of an analytical model describing the phenomena occurring during paper compression, and a method to determine the mechanism of paper destruction and the corresponding maximum force that destroys a paper sample.
Keywords: strength properties of paper; analysis of digital images; modelling of the shape of a paper sample; deflection arrow
Citation: Pełczyn´ ski, P.; Szewczyk, W.; Bien´ kowska, M.; Kołakowski, Z. A New Technique for Determining the Shape of a Paper Sample in In-Plane Compression Test Using Image Sequence Analysis. Appl. Sci. 2023 , 13 , 1389. https://doi.org/ 10.3390/app13031389
1. Introduction Paper is an orthotropic material commonly used for the production of corrugated and cellular cardboard, from which a variety of packaging is then produced [1,2]. Their usefulness is determined by the strength properties, which depend to a large extent on the properties of the paper itself [3–9]. At the same time, it is desirable to minimize the weight of the package while maintaining the required strength. In order to avoid time- consuming, experimental selection of the material composition of the cardboard from which the packaging is made, it is increasingly used to predict their strength properties by means of calculations that take into account the properties of the papers used in their production [10–14]. One of the important properties is the resistance to edge crushing measured in the compression test at short fastening—SCT [15]. Due to the orthotropy of the paper, resistance to crushing is determined in two main directions, namely MD (machine direction) and CD (cross direction). However, the test does not take into account the phenomenon of buckling of the tested sample, which occurs when using longer sample attachment lengths and is commonly ob- served in corrugated cardboard packaging. Analysis of the compressive strength of various materials in the buckling state has been of interest to researchers for many years because it is of great importance for estimating the load capacity of mechanical structures [16–19]. However, the study of paper properties in this area was usually limited to simple com- pression tests and was not combined with simultaneous observation of the shape of the compressed samples. Modern methods of processing and analyzing digital images make it possible to observe changes in the shape of bodies subjected to external forces on the basis of the
Academic Editor: Milena Pavl í kov á
Received: 21 December 2022 Revised: 11 January 2023 Accepted: 16 January 2023 Published: 20 January 2023
Copyright: © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).
Appl. Sci. 2023 , 13 , 1389. https://doi.org/10.3390/app13031389
https://www.mdpi.com/journal/applsci
Made with FlippingBook Digital Publishing Software