The aim of this study was to develop V-shape compression socks that should exert graduated lateral compression around the leg. For the development of socks, three types of yarns: main yarn (MY), plaiting yarn (PY) and inlaid yarn (IY) were used. Each yarn contained spandex yarn as the core. Machine adjustments were optimized to achieve the special V-shaped compression socks according to size of the wooden leg. Eighteen socks samples were developed and quantified for pressure exertion at ankle and calf portions using the MST MKIV, Salzmann pressure measuring device. Consequently, only two socks samples were accepted, which had the pressure exertion values of 21 mmHg and 23 mmHg with graduation percentage of 73% and 80%, respectively.
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This paper presents a theoretical and experimental study on lateral compression of square and rectangular metal columns. Some theoretical relations are derived to predict the absorbed energy, the specific absorbed energy and the instantaneous lateral load during the lateral compression. Analytical relations are obtained in two stages: elastic and plastic parts. In the plastic zone, the total absorbed energy by the column is calculated, based on the energy method. Then, an analytical equation is derived to predict the instantaneous lateral load. In the elastic part, the instantaneous load is obtained by linear behavior assumption. To verify the theoretical formulas, some lateral compression tests were carried out on square and rectangular columns and the experimental results are compared with the theoretical predictions, which shows a good agreement. Also, based on the experiments, effects of geometrical dimensions and material properties of the columns on the energy absorption capability are investigated. The results show that the absorbed energy by a column increases proportional to the column length. Also, columns with the thicker wall have the higher specific absorbed energy and so, rectangular columns with the thicker wall are the better energy absorbers during the flattening process. Also, the absorbed energy increases when the length of the column edge along which the load is applied decreases. Also, it is found that the specific absorbed energy by the aluminum columns is higher than the brazen ones and therefore, flattened columns with the high ratio of the flow stress/density are the better energy absorbers.
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