Effects of Waste Electronic Plastics and Marble Dust on Mechanical Behavior of High Strength Concrete

The influence of utilizing waste electronic plastic (e-plastic) and waste marble dust (MD) on the mechanical and durability properties of high strength concrete (HSC) were investigated. For this purpose, concrete mixtures with a water to cement ratio of 0.40 were prepared. Shredded e-plastic waste was utilized as a partial replacement of natural aggregate at proportions of 0%, 10%, 20%, 30% and 40% by volume. In addition, MD was used as an additive by weight of cement at the proportions ranging from 0% to 15%. The unit weight, compressive, splitting tensile and flexural strength values, modulus of elasticity, stress-strain relationship under compression, load deflection relation under flexure, toughness and permeability of the mixtures were determined. In addition, the impact of high temperatures (60ºC, 100ºC and 200ºC) on compressive strength and unit weight were determined and the obtained data were compared with the corresponding untreated specimens. Additionally, specimens were exposed up to the temperature of 300ºC to observe the temperature effect on the surface condition of concrete. Observed data indicated that the strength values, elastic modulus and unit weight of the test mixtures were lower than those of the control concrete. Furthermore, the least reduction in compressive strength, flexural strength and toughness occurred at 20% e-plastic replacement level. The tensile strengths, elastic modulus and unit weight were inversely proportional to the increment in the e-plastic content. On the other hand, the change in temperature resulted in the compressive strength loss up to 200ºC. Color changes were also observed on the concrete surfaces at 300ºC. TGA analysis of e-plastic particles also showed that weight losses became more pronounced at 300ºC compared to the 200ºC. Ultimately, the addition of MD slightly enhanced the properties and performance of the concrete.