The paper presented the possibility of manufacturing aggregates from industrial waste materials and their ecological benefits. The cold bonding process to create aggregates uses substantially less energy than the sintering technique. This study deals with the outcomes of an experimental assessment of the physical and strength properties of environment-friendly cold-bonded and sintered fly ash (FA), ground granulated blast furnace slag (GGBFS), and quartz (Q) lightweight aggregates. The waste materials were mixed with Portland cement at 20–50 percent by weight to make artificial lightweight aggregates. To investigate the impacts of temperature on the physical properties, such as crushing strength, density, and water absorption, the pellets were sintered at 300, 600, and 900 °C for an hour. The results show that all the produced aggregates might be categorized as lightweight aggregates due to the combinations' average densities being less than 2,000 kg/m3. The fly ash lightweight aggregates had higher density and crushing strength, as well as decreased water absorption. The density and crushing strength improved somewhat by raising the temperature, while the water absorption decreased with increased temperature. In this research, the most efficient mineral admixture concentration has been evaluated as 50 percent for both fly ash and ground granulated blast furnace slag and 30 percent for quartz for cold-bonded pellets. Furthermore, superior physical qualities have been reported at the 900 °C sintering temperature.

There is great growing concern regarding the environmental impact of the building and construction industry. Aggregate, one of the most crucial ingredients of concrete, is among the concerns in this regard. There will be a steady increase in demand for aggregates in the near future, but limited natural reserves will not be able to respond to this demand due to the risk of depletion. This current situation is forcing researchers to conduct new and artificial material production techniques that keep the resources within the allowed boundaries. Artificial aggregate production is one of the new methods for sustainable, environmentally friendly material production. The mechanical and environmental properties of lightweight concrete produced via artificial aggregates in different ratios were investigated in this study. Fly ash (FA), ground granulated blast-furnace slag (GGBFS), and quartz powder (QP) were utilized in the production of artificial lightweight aggregate (LWA) by using a special technique known as cold-bonding pelletization. The prepared concrete samples with the artificial aggregates were subjected to compressive, tensile, flexural, and bonding tests. The test results demonstrated that the bonding, tensile, and compressive strength values of lightweight concrete with a 20% GGBFS coarse aggregate replacement ratio of lightweight aggregates increased by 11%, 12%, and 30%, respectively. Moreover, it has been observed that a 41% increase in compressive strength is possible with a 40% QP coarse aggregate replacement ratio of lightweight aggregates. Finally, in addition to significantly impacting the mechanical properties of the lightweight concrete produced via artificial lightweight aggregates, we demonstrated that it is possible to control and reduce the harmful environmental effects of waste materials, such as FA, GGBFS, and QP in the present study.

Production of artificial aggregate which has the highest volume ingredient in concrete has gained great importance in the last decades. The fundemental cause for this is to reduce harmful environmental impacts. In addition, artificial aggregates are tried to be used to improve some important features of concrete. In the present study, the physical and mechanical properties of two types of artificial aggregates produced by cold bonding and sintering methods were compared. For this purpose, artificial aggregates pelletized and sintered at different temperatures were produced by using fly ash at different percentages. Dry density, specific density, water absorption and crushing strength tests were carried out to investigate the physical and mechanical properties of the produced artificial aggregates. The results showed that the bulk density and density values of sintered Fly ash artificial aggregates have a trend of rising but the water absorption values have a decreasing trend. The minimum and maximum density values were observed as for 50% sintered at 900 o C and 20 % cold bonded artificial lightweight aggregates respectively. Moreover the highest crushed strength value was measured as 945 N in samples with 50% Fly ash sintered at 900 o C.

This study found that one of the constructive, necessary, beneficial, most effective, and cost-effective ways to meet the great challenge of rising energy prices is to develop and improve energy quality and efficiency. The process of improving the quality of energy and its means has been carried out in many buildings and around the world. It was found that the thermal insulation process in buildings and educational facilities has become the primary tool for improving energy efficiency, enabling us to improve and develop the internal thermal environment quality processes recommended for users (student - teacher). An excellent and essential empirical study has been conducted to calculate the fundamental values ​​of thermal conductivity coefficient for different types of cement mortar, including the different concentrations of cellulosic fibers. And in our study, those cellulosic fibers obtained from sugarcane and sugarcane residues (agricultural waste materials) were used. The percentage is 10%; 20% and 30% of cellulose fibers were added to the cement mixtures. Then the differences are measured, specifically in the physical properties (heat capacity, density, and thermal conductivity coefficient) for 28 days. The Design-Builder program also implemented a precise simulation of the thermal loads of the external envelope of the educational building that is exposed to direct sunlight before and after the insulation process. It was found that with the use of thermal insulation material (meaning the cellulosic fiber technology) mixed with the cement mortar layer of the educational building, the given value of the heat transfer coefficient W/m2 Kelvin decreased by 47.2%. Accordingly, this contributed significantly to a significant and very significant saving in the values ​​of electrical energy consumption by 11.9% for cooling and heating operations and to reducing dangerous carbon dioxide emissions by 52.2%. The simulation has shown that applying thermal insulation techniques to all buildings and educational facilities is highly recommended to save a large consumption in the value of electrical energy and the costs of waste materials and to ensure integrated protection for the ecosystem.

In this experimental study, the use of stone powder as a stabilizer to the clayey soil studied. Tests of Atterberg limits, compaction, fall cone (FCT), Laboratory vane shear (LVT), and expansion index (EI) were carried out on soil-stone powder mixtures with fixed ratios of stone powder (0%, 5%, 10%, 15%, and 20%) by the dry weight. Results indicated that the undrained shear strength obtained from FCT and LVT increased at all the admixture ratios, and the expansion index reduced with the increase of the stone powder.