Production of Nano cement using Nanotechnology is considered a new potential approach in the construction material industry. It has the ability to decrease the size of the cement particle to the Nano scale which increases the cement chemical activity. In this technology, high-performance cement is produced while preserving the environment. To evaluate the economics of establishing a Nano cement unit in an existing typical factory in Egypt, the Cement Factories on canal way in Egypt are selected as a case study. The economic indicators used for the evaluation include Net Present Value (NPV), Internal Rate of Return (IRR), and Break Even Point (BEP). The results were used to decide on the feasibility of building Nano cement unit. It was found that Net Present Value has a positive amount between two interest rate 10% to 30%. The Internal Rate of Return indicator requires increasing the revenue by 38.80% above the interest rate of Central Bank of Egypt. Finally, Break Even Point is gained before one year of production of 720000 ton annually and within 6 years at variable cost/price. Therefore, establishing the product line of Nano cement in Egypt raises the economic return and enhances the concrete quality.

The partial replacement of cement with nanomaterials such as nanosilica (NS) particles in concrete improves its strength and other properties. In this study, the effect of NS as a partial replacement of cement for concrete mixes and concrete beams was examined. The studied response characteristics of reinforced concrete beams included the compressive strength, failure mechanisms, load-carrying capacity and load–deflection behaviour. The results showed that compressive strength increased with an increase in NS content up to 2.0% replacement of cement weight. The rate of increase in compressive strength was no longer significant beyond 2.0% replacement, indeed there was a slight decrease in compressive strength for NS content of 3.0%. The effect of increased NS content on the flexural behaviour of beams was also studied. Increased NS content led to increases in the first-cracking and ultimate loads and reductions in the deflection at cracking and ultimate load levels. No major differences in the structural response parameters were observed for test beams with zoning of NS in the bottom tension or top compression zones. An increase in NS content led to a slight increase in the ultimate strain associated with the ultimate load. Good agreement was found between experimental and theoretical ultimate moments.

Artificial Neural Network (ANN) modelswere built to expect the compression strength of various types of concrete incorporatingnano silica (NS) and silica fume (SF) as partial cement replacement. The mixtures data used in the networks model,which was collected from previous researchers, studied the effect of NS and SF on concrete. The previous researchers experimentally tested the specimens containing up to 10% of NS and up to 20% of SF as a partial cement replacement at age 7 and 28 days. A total of 488 experiments were used as data sets to train and test the network. The input parameters, like cement content, nano silica, water to cement ratio, and aggregate type and proportion, were varied for each experiment. Three sets of data were modeled using ANNs for both ages 7 and 28 days to predict the strength. The maximum average error of the three models did not exceed 10% of the exact result.

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Application of modern techniques to rehabilitate structural elements due to aging and/or flexural cracks is of great concern by many researchers. In the current research, high strength epoxy matrix incorporated Carbon Nano Tubes (CNT) was used to bridge up the gaps in the vicinity of flexural cracks. First, the physical properties of CNT were studied followed by mechanical examination of the epoxy resin with/without CNT. The dynamic behavior of simply supported concrete and steel beams, as well as a cantilever steel beam was investigated. All the examined beams were excited by a light impact hummer at their sound, cracked, and repaired states. The free vibration response was collected, processed and the modal parameters were obtained. The change in the dominant natural frequency and damping ratio were investigated in each of the examined condition. The degradation in the beams was created by generating synthetic cracks at the locations of maximum bending moment using a saw cut. Furthermore, intensive numerical finite element modelling (FEM) was carried out using (ANSYS). The obtained numerical results were of great coincidence to the experimental work. It was concluded that the use of epoxy matrix containing CNT enhanced the dynamic properties of the cracked beams and was able to restore the integrity of the beams to a condition slightly the same as their original sound states.