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. Doi: 10.28991/cej-2021-03091649 Full Text: PDF

To study the influences of the nanomaterial upon the microstructure of the interfacial transition region of mortar that prepared with a composite binder comprising nanomaterial and to clarify its effect on the 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 ascibed to the microstructure amelioration of the interfacial transition region. In addition, the XRD analysis and the SEM micrographs elucidated the formation of hydration compounds and the enhancement in bonding due to the existence of nanoparticles.

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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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.