This study aims to investigate the applicability of using waste materials produced in Kuwait as partial replacements of conventional concrete materials in self-consolidating, high-performance concrete. Processed ceramic products, along with steel slag obtained from electric-arc furnaces, were used as partial replacements of coarse and fine aggregate at various dosages. The fresh and hardened properties of the concrete were then measured and compared. Results have shown that using crushed ceramic products (in the form of sand-like and 3/16” aggregates) increases the rate of strength gain as the concrete cures, while using electric-arc furnace slag to replace 3/8” aggregates increases the compressive strength when compared to a benchmark mix.

The purpose of this paper is to examine the effects of introducing waste materials sourced from factories in Kuwait as partial replacements of conventional concrete materials. Rejected ceramic products and unused electric-arc furnace slag were treated and partially replaced portions of coarse and fine aggregates, and the possibility of partially replacing cement was also examined. Initial results showed that all aggregate sizes can be replaced with either of the waste materials without compromising the concrete’s rheological properties or compressive strength. Additionally, pulverized ceramic powder was shown to improve the compressive strength of mortar cube samples. Finally, the two waste materials were combined in hybrid mixes that aimed to have the highest utilization of waste materials while maintaining (if not improving) the properties of a previously established benchmark self-consolidating concrete (SCC) mix. The results of this study show that waste materials sourced from landfills in Kuwait can be repurposed to replace portions of conventional construction materials in a self-consolidating, high-performance concrete mix with significantly better mechanical properties and higher compressive strength than that shown by a benchmark mix.

The phenomenon of dumping used tires in Kuwait has reached critical levels, with a landfill containing millions of tires being formed in a remote area, which is a major environmental hazard. Nowadays, recycled rubber is used as a suitable and useful material in civil engineering applications, particularly in the production of “green concrete”. This study aims to see whether recycled tire by-products can be used to make “green concrete” for pavements. Each type of tire by-product was tested individually to examine its properties and effects on a benchmark mix before creating hybrid mixes that contain a combination of the materials. Eleven mixes containing different doses of shredded or crumbed rubber or steel fibers contained within the tires were made to evaluate their impact on the concrete’s slump, compressive strength, split tensile strength, and modulus of rupture. Additionally, twelve hybrid concrete mixes containing different doses of various tire by-products were developed. Preliminary results show that the incorporation of rubber products has a reduction on the concrete’s properties. The use of replacement materials sourced from recycled tires using the dosages investigated in this study does not detract from the usability of green pavement concrete suited for hot weather. The concrete produced in this study could be evaluated for specific properties relating to its road safety in further studies. Additionally, long-term effects of using the concrete can be studied using finite element analysis.

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