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- This paper investigated the effect of incorporating two types of micro particles micro CaCO3 and micro SiO2 on mechanical properties and durability of concrete. Micro materials were added in four different dosages of 1%, 2%, 3% and 4% by weight as partial replacement of cement in concrete mixture. Mechanical properties of hardened concrete (compressive strength, flexural strength and split tensile strength) have been done after 28 days of water curing. In addition, water absorption test was carrying out for obtaining the durability properties of concrete specimen. Binary combination of micro CaCO3 + micro SiO2 were also studied the combined effect of the micro particles. Micro-structural characteristic of modified concrete was done through the scanning electron microscope. The results showed that incorporation of micro CaCO3 and micro SiO2 particles lead to increase the packing and enhance the mechanical properties and durability of concrete. A significant performance was observed in case of micro silica addition to the concrete in comparing with other micro particles.

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In the present study, the compressive strength assessments of cement mortar containing different amounts of ZrO2, SiO2, Al2O3 and CaCO3 nanoparticles have been investigated. Four different contents for each nanoparticles type were utilized as a partial replacement of cement 1%, 1.5%, 3% and 5% by the cement weight. The compressive strength was estimated for two ages (7) and (28) days. The end results manifested that the specimens’ compressive strength enhanced via the addition of the nanoparticles of ZrO2 and SiO2 to the paste of cement till 3.0% and then decreased but remained greater than the reference mix. While, the compressive strength of specimens enhanced via the addition of the nanoparticles of Al2O3 and CaCO3 ZrO2 up to 5%. Maximum compressive strength recorded was 42.5 MPa for mixes with 3% nano SiO2 followed by 38 MPa, 37 MPa and 33.5 MPa for mixes with 4% nano Al2O3, 3% nano and ZrO2 and 4% nano CaCO3, respectively.

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. In this study, polymer composites were manufactured with epoxy-based resin and wastes as a mineral additive. The wastes including a high content of silica (Silica fume, glass and fly ash) powder were used as fillers for an epoxy adhesive to improve its wear resistance properties. They were supplemented to mixes in various ratios via substituting the resin from 0 to 20% by weight. Tests of wear rate and hardness were conducted upon all-polymer composites at all fillers ratios. Results indicated that the epoxy hardness increased with increasing the filler addition. Consequently, the addition of wastes that include silica raised the wear resistance of polymer composites; nevertheless, it caused the composites harder materials. The wear rate decreased with increasing the silica fume, glass, and fly ash addition. In the case of fly ash addition, the minimum wear rate was at 15%, and after this percentage, the wear rate increased. However, in the case of glass addition, the minimum wear rate was at 10%, and after this percentage, the wear rate increased

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Silica is considered one of the most prevalent components in the Earth’s shell and is synthesized for use in technological applications. Nevertheless, new methods for finding a better, cheaper, and more ecologically friendly supply of silica with less energy consumption are unavoidable. This study investigates whether nanopowders made from waste with a great silica amount (fly ash and glass) can be utilized as fillers in an epoxy glue to enhance its characteristics. Four different contents (5, 10, 15, and 20 wt%) of nano–fly ash, nanoglass, and nanosilica powder were introduced into the samples. Fourier transform infrared analysis, differential scanning calorimetry analysis, viscosity testing, and microhardness testing were conducted for nanoglass/epoxy and nano–fly ash/epoxy samples, which were compared with the silica/epoxy samples. Results indicated that the nanoglass and nano–fly ash powder have the same impact as nanosilica on the characteristics of epoxy. The hardness and viscosity of epoxy increased with the increase in the added filler. At 20 wt%, the hardness value of the nanoglass/epoxy composites was greater than that of the nanosilica/epoxy and fly ash/epoxy composites by about 15% and 7%, respectively. The results also indicated that the highest viscosity values were obtained when using nano–fly ash powder of 20 wt%. Furthermore, the modification of the epoxy by the nanoparticles had no significant effect on the values of the glass transition temperatures

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This paper investigates the effect of nano-papyrus cane ash as an additive on concretes’ mechanical and physical properties. Three types of concrete mixtures, 1:2:4, 1:1.5:3, and 1:1:2 were prepared for each mixture, nano-papyrus ash was added in five different dosages of 0.75, 1.5, 3, 4.5, and 6% by weight of cement; therefore, eighteen mixes would be studied in this work. Physical properties represented by dry density and slump were also measured for each mix. Moreover, to evaluate the mechanical properties development split tensile strength and compressive strength were obtained at age (7 and 28). Results manifested that the adding of nano ash developed the compressive strength and split tensile strength of concrete and the maximum enhancement recognized in the mixes with a content of 4.5% nano-papyrus in each studied mixture in this work. The slump test results indicated that the workability of concrete increased with adding nano-papyrus ash gradually with increasing nanoparticles' content. As well as, dry density was significant increased with nano-papyrus ratio; greater values were recorded in mixtures with 1.5-4.5% content of nano-papyrus. When comparing the concrete mixes used, it was found that the best results were obtained with 1:1:2 mixtures. This remarkable improvement in concrete properties considers the nano-papyrus is considered a cement economical and useful replacement for traditional construction material.

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Cement production uses large quantities of natural resources and contributes to the release of CO2 . In order to treat the environmental effects related to cement manufacturing, there is a need to improve alternative binders to make concrete. Accordingly, extensive study is ongoing into the utilization of cement replacements, using many waste materials and industrial. This paper introduces the results of experimental investigations upon the mortar study with the partial cement replacement. Fly ash, silica fume and glass powder were used as a partial replacement, and cement was replaced by 0%, 1%, 1.5%, 3% and 5% of each replacement by the weight. Compressive strength test was conducted upon specimens at the age of 7 and 28 days. Microstructural characteristic of the modified mortar was done through the scanning electron microscope (SEM) vision, and X-ray diffraction (XRD) analysis was carried out for mixes with different replacements. The tests results were compared with the control mix. The results manifested that all replacements present the development of strength; this improvement was less in the early ages and raised at the higher ages in comparison with the control specimens. Microstructural analysis showed the formation of hydration compounds in mortar paste for each replacement. This study concluded that the strength significantly improved by adding 5% of silica fume compared with fly ash and glass powder

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To study the effects of nanomaterials on the microscopic structure of the mortar interconnection zone that is prepared by a compound bond comprising nanomaterials. And to clarify its impact on compressive strength improvement. In this study, the compressive strength, SEM analysis and XRD analysis were estimated for mortar containing different amounts of ZrO2, SiO2, Al2O3 and CaCO3 nanoparticles. Four different contents of each nanoparticles' types were used as a partial replacement of cement with 1%, 1.5%, 3% and 5% by the weight of cement. Results manifested that the mortar compressive strength enhancement can be ascribed to the microstructure amelioration of the interfacial transition region. Besides, XRD analysis and SEM micrographs elucidated the formation of hydration compounds and the improvement in bonding due to the existence of nanoparticles

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In this paper, mixing of the recycled glass, which possesses a high SiO2 (silicon dioxide) percentage, was utilized to produce a green concrete with remarkable properties. Waste glasses were utilized as cement or fine aggregate partial replacement with various contents (5%, 10%, 15% and 20%) via the weight of cement or fine aggregate. The compressive strength for three ages (7, 14, and 28) days and slump was measured for each concrete mix. Results evinced that the recorded compressive strength increased with the glass content up to10% and then decreased when using glass as replacement of cement, while when using glass as replacement for fine aggregate, the compressive strength decreased initially and then increased with the content of glass. The results of slump test manifested that the concrete workability increased with the content of glass whether the powder of glass employed as cement or fine aggregate replacement.

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Autoclaved aerated concrete (called Thermostone in Iraq) is one of the popular building materials that are used in various purposes in construction industries. It is factory-made material that can be moulded into blocks which can be used in framework buildings. However, these buildings are under the risk of fire since it has different cusses such as arson and electrical short circuit. It is important to find ways to improve counter such phenomenon. Therefore the objective of this paper is investigating the fire resistance performance of Thermostone with and without plastering. Five different samples were used for the test, four of them were covered with different types of plastering. Three tests were employed for this study: Compressive, absorption, and density test. For all tests, the samples were exposed to elevated temperatures from 250°C to 900°C. It was shown that the compressive strength are reduced when exposed to high temperature by up to 75%, however the air-cooled samples are less affected by approximately 15%. Furthermore, plastered samples has lower absorption rate than non-plastered ones. Finally, density decrease with heat by up 10% approximately

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