Al–10% Al2O3-10% ZrO2 nanocomposite powders were fabricated by high-energy milling of the blended component powders. Planetary Monomill "Pulverisette 6" was used in milling the powders for 45 hours at 300 rpm and a ball-opowder ratio of 10:1. A uniform distribution of the Al2O3 and ZrO2 reinforcements in the Al matrix was ccessfully obtained after powders milling process. This uniform distribution was confirmed by characterizing these nanocomposite powders by scanning electron microscopy (SEM). X-ray diffraction (XRD) patterns were recorded for the milled powders, and analyzed using Williamson–Hall method to determine the crystallite size and the lattice strain. The crystallite size measurements were obtained using TEM observations in order to compare these results with those obtained from XRD

Al–10% Al2O3-10% ZrO2 nanocomposite powders were fabricated by high-energy milling of the blended component powders. Planetary Monomill "Pulverisette 6" was used in milling the powders for 45 hours at 300 rpm and a ball-opowder ratio of 10:1. A uniform distribution of the Al2O3 and ZrO2 reinforcements in the Al matrix was ccessfully obtained after powders milling process. This uniform distribution was confirmed by characterizing these nanocomposite powders by scanning electron microscopy (SEM). X-ray diffraction (XRD) patterns were recorded for the milled powders, and analyzed using Williamson–Hall method to determine the crystallite size and the lattice strain. The crystallite size measurements were obtained using TEM observations in order to compare these results with those obtained from XRD

In this Study four Sandstone rocks were drilled by diamond core bit using a fixed laboratory-drilling machine at 400 and 1200 rpm, rotary speed, over a range of weights on bit (WOB) 12,18,24,30,………kg. Operating parameters of the drill bit such as WOB, penetration rate (PR), torque (T), and specific energy (SE)were continuously monitored during the drilling trials. Besides the effects of formation properties on the penetration rate were monitored. Relationships between WOB and both PR, torque T and Se were described and the relationship between PR and SE was given. Graphs are presented and can be used to predict diamond-drilling performance easy and fast.

In this Study four Sandstone rocks were drilled by diamond core bit using a fixed laboratory-drilling machine at 400 and 1200 rpm, rotary speed, over a range of weights on bit (WOB) 12,18,24,30,………kg. Operating parameters of the drill bit such as WOB, penetration rate (PR), torque (T), and specific energy (SE)were continuously monitored during the drilling trials. Besides the effects of formation properties on the penetration rate were monitored. Relationships between WOB and both PR, torque T and Se were described and the relationship between PR and SE was given. Graphs are presented and can be used to predict diamond-drilling performance easy and fast.

It is very important to determine the optimum utility of any limestone deposit according to the physical and mechanical properties. The quality index is a good way for this aim. The physical properties such as porosity, density and water absorption and mechanical properties such as compressive-, tensile-strength and coefficient of dynamic fragmentation, control the optimal use of limestone as building, road construction and cement manufacture. These parameters are determined for several locations in Egypt and the quality index for each location is calculated, and the optimal use is determined.

It is very important to determine the optimum utility of any limestone deposit according to the physical and mechanical properties. The quality index is a good way for this aim. The physical properties such as porosity, density and water absorption and mechanical properties such as compressive-, tensile-strength and coefficient of dynamic fragmentation, control the optimal use of limestone as building, road construction and cement manufacture. These parameters are determined for several locations in Egypt and the quality index for each location is calculated, and the optimal use is determined.

It is very important to determine the optimum utility of any limestone deposit according to the physical and mechanical properties. The quality index is a good way for this aim. The physical properties such as porosity, density and water absorption and mechanical properties such as compressive-, tensile-strength and coefficient of dynamic fragmentation, control the optimal use of limestone as building, road construction and cement manufacture. These parameters are determined for several locations in Egypt and the quality index for each location is calculated, and the optimal use is determined.

Use of FRP re-bars has increased rabidly since the last decade to avoid the deterioration of concrete structures caused by corrosion of steel reinforcement. Since FRP bars made from high tensile strength fibers such as carbon, glass, aramid and basalt embedded in polymeric matrices, they are anti-corrosion materials. However, the mechanical properties for FRP are different from steel bars; some types of FRP bars have a low relatively modulus of elasticity in comparison with conventional steel bars. Therefore shear capacity of RC beams reinforced with FRP bars could be different than those reinforced with steel bars, in this study a parametric analysis based on the finite element simulation was devoted to evaluate the effect of the axial stiffness of the reinforcement when FRP bars are used on the shear strength of RC beams. The analysis program consisted of two series of beams with concrete compressive strength 13 MPa and 33.5 MPa with six values for the elastic modulus of the reinforcement 35, 51.5,100,150,209 and 300 GPa with reinforcement ratio 0.91% and shear span to depth ratio 3.0, It was found that the reinforcement axial stiffness significantly influences the depth of compression zone and the shear strength of beams as well as the service load.

Use of FRP re-bars has increased rabidly since the last decade to avoid the deterioration of concrete structures caused by corrosion of steel reinforcement. Since FRP bars made from high tensile strength fibers such as carbon, glass, aramid and basalt embedded in polymeric matrices, they are anti-corrosion materials. However, the mechanical properties for FRP are different from steel bars; some types of FRP bars have a low relatively modulus of elasticity in comparison with conventional steel bars. Therefore shear capacity of RC beams reinforced with FRP bars could be different than those reinforced with steel bars, in this study a parametric analysis based on the finite element simulation was devoted to evaluate the effect of the axial stiffness of the reinforcement when FRP bars are used on the shear strength of RC beams. The analysis program consisted of two series of beams with concrete compressive strength 13 MPa and 33.5 MPa with six values for the elastic modulus of the reinforcement 35, 51.5,100,150,209 and 300 GPa with reinforcement ratio 0.91% and shear span to depth ratio 3.0, It was found that the reinforcement axial stiffness significantly influences the depth of compression zone and the shear strength of beams as well as the service load.

Use of FRP re-bars has increased rabidly since the last decade to avoid the deterioration of concrete structures caused by corrosion of steel reinforcement. Since FRP bars made from high tensile strength fibers such as carbon, glass, aramid and basalt embedded in polymeric matrices, they are anti-corrosion materials. However, the mechanical properties for FRP are different from steel bars; some types of FRP bars have a low relatively modulus of elasticity in comparison with conventional steel bars. Therefore shear capacity of RC beams reinforced with FRP bars could be different than those reinforced with steel bars, in this study a parametric analysis based on the finite element simulation was devoted to evaluate the effect of the axial stiffness of the reinforcement when FRP bars are used on the shear strength of RC beams. The analysis program consisted of two series of beams with concrete compressive strength 13 MPa and 33.5 MPa with six values for the elastic modulus of the reinforcement 35, 51.5,100,150,209 and 300 GPa with reinforcement ratio 0.91% and shear span to depth ratio 3.0, It was found that the reinforcement axial stiffness significantly influences the depth of compression zone and the shear strength of beams as well as the service load.