Thermo-physiological properties and burning behaviours of automotive upholstery fabrics woven with aramid and wool yarns

Today, people’s expectations of cars have changed because they travel more frequently and take much longer trips in their automobiles. Therefore, auto manufacturers have come to realize that comfort properties of automobiles should be improved in addition to their mechanical, technical and aesthetical properties. This study aimed to investigate the thermophysiological properties of the automotive upholstery woven fabrics produced with different blend ratios of flame resistant meta-aramid and wool yarns. For this purpose, twenty-eight automotive upholstery woven fabric samples were produced using two different weaving patterns and different blend ratios of flame resistant meta-aramid and wool yarns. Thermophysiological properties of the samples such as water vapor permeabilities, air permeabilities and thermal conductivities were measured, and their burning behaviours were tested according to the standards. The results obtained in this study were assessed by means of statistical methods, and the results of the statistical analysis showed that blending ratios of flame resistant meta-aramid and wool fiber had statistically significant effects on both the thermo-physiological properties and burning behaviours of automotive upholstery fabrics. This study showed that the thermal comfort values of the automotive upholstery fabrics of different meta-aramid/wool blend ratios were very close to one another. In addition, the air permeability values of these fabrics were increased with the increase of the meta-aramid content in the blend. The blends containing 25% meta-aramid fiber exhibited the highest increases in air permeability values of the fabrics. Besides, the blend of 25% meta-aramid and 75% wool fiber was found to be the optimal blending ratio in terms of the total burning time after the removal of the ignition source. Therefore, it can be concluded that thermo-physiological comfort properties and burning behaviours of automotive upholstery fabrics can be improved by using the blends with different meta-aramid contents, depending on desired fire performance levels and thermophysical properties.

Performance of Bio Concrete by Using Bacillus Pasteurii Bacteria

In concrete, cracking is a common phenomenon due to its relatively low tensile strength‎ ‎, which occurs due to external loads and imposed deformations‎‎. The main research objective is to create a kind of self-healing concrete by employing mineral producing bacteria Bacillus pasteurii‎ to locate the rift in the most favourable circumstances for autogenous healing to take place. Self-healing concrete containing bacteria has been generated for this study through the application of bacterial self-healing elements as ‎spores ‎and nutrients with different percentages of bacteria ranging from (10% - 25%) as a replacement of mixing water is added at the time of pouring. The bacteria influence was observed by Scanning Electron Microscope (SEM) and with Energy ‎Dispersive X-ray Spectrometer. The mechanical properties and durability of a thirty-five mixture were ‎examined. The optimal blending content proportion was ‎10SF20BC, which showed an increment in compressive strength and flexural strength compared to the control mixture ‎to ‎reach 79.16%, 50% respectively and 24.38% enhancement in sulfate resistance. The highest percentage of calcium carbonate precipitations was ‎9.49% of a weight of ‎mixtures ‎elements, which, in turn, revealed the highest area repair rate, which was able to fill the ‎crack with widths leads to 0.80 mm.