No abstract

No abstract

Many engineering designs focus on the production of durable, ergonomic, and economical new materials. In today’s world where natural resources are rapidly decreasing, recycling waste materials is of great importance. As a result of the bending test, the sample’s return to its original dimensions shows the plastic feature of the material. It was observed that the tensile strength can be increased if the speed of the injection machine is well adjusted in the production of tensile strength testing samples. There was an increase in the screw tensile strength of the samples and the joint hardness strength. Thermogravimetric analysis (TGA) showed that the reference samples were completely crumbled around 480 °C, and it was observed that only quartz remained from the input materials. Differential scanning calorimetry (DSC) showed that the peak point in the reference sample was at the heat flow rate of 29 m/W, while it was 18 to 19 m/W in the doped groups. Melting temperature was observed in the range of 125 to 135 °C in all groups. The mechanical properties of the quartz-substituted samples increased compared to the reference sample. It was observed that the quartz and wood powder contained in the mixture worked in harmony.

In the world where natural resources are rapidly decreasing, an activity in which developed and developing countries act with a common mind is the reutilisation of wastes with recycling methods. In this study, cracks and breaks did not occur because of the harmony of the materials in the mixture according to the experimental results applied to wood powder, polypropylene and quartz. As the amount of quartz increased, the hardness resistance values also increased. According to a thermogravimetric analysis graphic, it has been observed that weight loss started after 250°C; wood and quartz were exposed to weight loss up to 500°C and then wood powder completely disappeared and only quartz remained. The prediction that the quartz mineral in the mixture might be fragile because of its hardness did not occur. It has been determined that the materials used in the composite material were compatible with each other.

Presence of alkali silica in aggregates that are used in concrete production causes formation of cracks and decrease of performance over time in concrete.The first damage caused by ASR in Turkey had been observed in certain highway bridges in Izmir locality in 1995. It was found that some aggregates in other regions of Turkey also have a character to cause ASR.The purpose of the study was to minimize potential alkali silica reaction expansion in concrete and mortars produced with the aggregates that are used in constructions in our region.Accelerated mortar bar test method was employed in the study. It was observed in experimental study that that the use of 20-25% fly ash, 25-35% blast furnace slag and 10% silica fume and metakaolin as mineral additive reduced ASR.According to optimization studies, it is appropriate to use 5-10% silica fume, 5% metakaolin, 10-15% blast furnace slag and 10-20% fly ash as mineral additive in optimum mixtures giving ideal expansion value.It was found that the use of 65% of cement together with 35% silica fume, metakaolin, blast furnace slag and fly ash in mineral additive combinations prevents ASR.