جستجوی مقالات مرتبط با کلیدواژه « پارچه حلقوی پودی » در نشریات گروه « مهندسی شیمی، نفت و پلیمر »

Reinforcement of civil structures that do not have sufficient resistance to the applied loads is of particularimportance. There are several ways to reinforce concrete structures so far. One of these methods is to usewinding technique on a concrete structure with a fabric. In this study, first, rib knitted structures with andwithout weft inserted yarn were fabricated with two types of ordinary and high tenacity polyester yarn(with a low and high modulus). Then concrete columns were made and winded using produced fabricswith and without tension. The compression test was carried out on the winded columns. The results showthat with increasing tensile modulus of the fabric (such as weft inserted rib fabric with high tenacitypolyester yarn) the compressive strength of the concrete columns increases. Accordingly, while thesample had only 7.52% weight increase and 8.75% increase in diameter compared to the control sample,the bearing capacity of the column showed an increase of 88.55% compared to the control sample. Also,the compressive strength of concrete column is increased by increasing the number of layers windedaround the concrete column.

Different samples were mercerized to evaluate the interactive effect of temperature and alkali concentration on dye absorption of plain knitted fabrics. The mass of dye picked up by mercerized knitted fabric was estimated by assessment of the wastewater of dyeing process. In order to observe the microstructural changes of the mercerized fabrics, FTIR spectra were recorded for gray fabric and mercerized samples with maximum dye absorption. The results of this study showed that, absorption performance of the mercerized samples was much more superior to that of gray fabric. The dyeing rate increased by alkali concentration at low temperature. Optimum alkali concentration dropped by increases in temperature as in bath temperatures of 40 and 60°C the optimum alkali concentrations were 250 and 200 g/L respectively. In addition to above results, dye absorption decreased by further increase in bath temperature. With the increase in alkali concentration, although the absorption peak appeared at 40°C but the mass of the dye picked up by the fabrics was decreased. Finally, the alkali concentration of 200 g/L at temperature of 60°C were considered the most suitable conditions for mercerization of cotton plain knitted fabric.