Worldwide, vast amounts of waste are produced every year and most waste is sent directly to landfills or burnt, which has severe and harmful impacts on the environment. Recycling waste materials is considered the most visible solution to protect the environment. Using scraps in concrete production is a proper method for getting rid of wastes, improving the characteristics of concrete, reducing the consumption of natural aggregates, and can be used as cementitious materials that decrease cement production so that the CO₂ that is produced during cement manufacturing decreases. This review paper summarizes the use of recycled waste materials, including rubber tires, crushed glass, and crushed clay brick in concrete, as a fractional replacement of aggregates, cement, etc., to develop eco-friendly lightweight construction materials. It has been concluded that the dry density of sustainable concrete decreased to 4, 21.7, and 31.7% when crushed glass, clay brick, and rubber tire were incorporated into the concrete instead of traditional aggregate, respectively. Waste rubber has good results in sulfate, thermal, and impact resistance, while glass powder and finely crushed clay brick helped to improve mechanical properties by increasing reach by 33% for glass and a slight increase for crushed clay brick, as well as thermal resistance compared to normal concrete. Moreover, due to the low particle density of these waste materials compared to that of normal-weight aggregates, these materials can be utilized efficiently to produce lightweight concrete for structural and non-structural applications such as road engineering, flooring for mounting machinery, highway and rail crash barriers, permeable pavement, interlocking bricks, insulation, filling concrete, and bearing walls.

The utilization of waste crushed clay brick (CB) in concrete reduces its harmful impacts on the environment as it can be found in many places around the world. This research studies the possibility of using clay brick powder (CBP) as a filler material to produce lightweight concrete as it has been exposed to high temperatures during manufacturing of the bricks, which increases its pozzolanic reactivity. The effect of using an air-entraining agent (AEA) for additional pore formation on concrete performance was evaluated. Eight mixtures were prepared and examined to achieve the research objectives. Concrete flowability, dry density, compressive strength, ultrasonic pulse velocity, thermal conductivity, sorptivity, and porosity were measured. Additionally, scanning electron microscopy, X-ray diffraction, thermo-gravimetric analysis, and mercury intrusion porosimetry were used to analyze the microstructure characteristics of the concrete. The results indicate that the use of CBP as filler material enhances the mechanical and durability characteristics of the concrete. In contrast, adding an AEA has negative effects on concrete’s mechanical and durability properties, but on the other hand, its use enhances the thermal properties of the concrete.

Experimental work was carried out to study new fine aggregate shielding construction materials, namely black sand (BS). The BS effect on the mechanical, durability, and shielding characteristics of heavyweight high-performance concrete (HWHPC) was evaluated. This study aimed at improving various HWHPC properties, concertedly. Fifteen mixtures of HWHPC were made, with various variables, including replacing 10% and 15% of the cement with fly ash (FA) and replacing normal sand by BS at various contents (15%, 30%, 45%, 60%, 75%, and 100%). The test specimens were subjected to various exposure conditions, including elevated temperatures, which ranged from 250 °C to 750 °C, for a duration of 3 h; magnesium sulfate (MS) exposure; and gamma-ray exposure. The effects of elevated temperature and sulfate resistance on concrete mass loss were examined. The results revealed that BS is a promising shielding construction material. The BS content is the most important factor influencing concrete compressive strength. Mixes containing 15% BS demonstrated significantly better strength compared to the control mixes. Exposure to 250 °C led to a notable increase in compressive strength. BS showed a significant effect on HWHPC fire resistance properties, especially at 750 °C and a significant linear attenuation coefficient. Using 10% FA with 15% BS was the most effective mixing proportion for improving all HWHPC properties concertedly, especially at greater ages.

Recycling solid waste is an economical path to protect the environment’s resources, shield the ecosystems, and reduce the need for raw materials. Ultra-high-performance geopolymer concrete (UHPGC)-based waste materials (WMs) were developed to achieve better mechanical performance with more economic and ecological benefits. This study aims to assess how powdered waste materials (PWMs) affect the performance of UHPGC as an environmentally friendly material. Overall, twenty-nine specimens were included with granite waste powder (GWP), basalt waste powder (BWP), waste glass powder (WGP), and marble waste powder (MWP). The workability, splitting tensile strength, compressive strength, and flexural strength were evaluated through experiments. Additionally, the durability and microstructure properties of PWMs-based UHPGC were investigated using the sorptivity test, elevated temperature resistance, SEM, and XRF. Three systems (solo, hybrid, and trinary) were used to add PWMs at four doses (25%, 50%, 75%, and 100%) to replace fine aggregates entirely or partially. Thirty percent of the binding materials were replaced with GWP to create the mixtures. The results of the studies showed that the ideal dosage for improving the mechanical and microstructural properties of PWMs-based UHPGC was the optimal substitution ratio, employing the trinary system with 33% of WGP, MWP, and BWP, was 25% at 90 d. The features decrease noticeably when the replacement ratio rises to 100%. The study’s findings, therefore, demonstrated that PWMs may be effectively employed in UHPGC while still producing concrete with sufficient characteristics for various applications.