Theoretical Analysis of Factors Affecting Ultimate Nominal Load of Reinforced Concrete Axially Loaded Short Squire Columns (Pu) Comparing use Prokon Program

One of this theoretical study, parameters that affecting the ultimate load capacity of the axially loaded column are studied. The parameters such as compressive strength of concrete and steel reinforcement ratio. Throughout study a different value of each factor will be assumed. Then the nominal load-carrying capacity of axially loaded column was calculated for these different factors parameters according using the simplified methods provided in (ACI-318- 14) building code requirement for structural concrete and Prokon Program. It is observed that increasing the compressive strength of concrete result in improving the ultimate load capacity. Using compressive strength of concrete more than 40MPa which results in increasing of (Pu) from (2362kN) to(5918KN) . On other hand The total area of longitudinal reinforcement bars (AST), and the gross area of concrete section (Ag) have a significant effects also on increasing of (Pu) value but not as (Fcʹ).

Strengthening of concrete square column using FRP composites

Strength and energy absorption capacity are the important parameter for axially loaded column. This paper investigates the strength of unconfined square concrete column and externally confined square column with fiber-reinforced (FRP) composites with synthetic carbon fiber and natural banana fiber. This type of strengthening of column is widely accepted in practice. Axial strength test is performed on confined square column with different parameters such as number of layers of FRP materials, wrapping patters like full wrapping, center wrapping and hybrid pattern. Both natural and synthetic fibers are used for FRP-confined square concrete column. It was found that external confinement using FRP material improved the axial-load carrying capacity, load-deformation and ductility of the square column compared to the unconfined square column.

Purification of liquid scintillation waste from binding radionuclides using different adsorbents

The quantity of liquid organic radioactive wastes produced by the use of radioactive materials in nuclear research facilities is small compared to aqueous radioactive waste, but a special and low-cost treatment method is needed. Here we investigated the adsorption performance of five materials, namely: KU-2 resin, bentonite, charcoal (M&S) and clay adsorbents for the successful removal of 90Sr/90Y from liquid scintillation cocktail waste. The batch adsorption technique (influence of pH, contact time, and temperature), sequential, and column technique were investigated. The efficiency of these adsorbents for the removal of 90Sr/90Y is in this order, resin > bentonite > clay with removal efficiency 90 ± 5.2, 68 ± 3.25, and 65 ± 5.3%, respectively. While charcoal has lower affinity for the sorption processes. Purification of liquid scintillation (LS) cocktail by separation of 90Sr/90Y was successfully carried out by packed column with KU-2 resin. The exhausted loaded column with 90Sr/90Y is successfully regenerated by 25 mL, 1 M HNO3. Characterizations of the original and the purified LS cocktail were carried out using FTIR analysis. The efficiency of the purified liquid scintillation waste (LSW) for the determination of radionuclide is about 62.67 ± 4.8.

Numerical Simulations of Destructive Tests of Cast Iron Columns Strengthened with a CFRP Coating

In many cases, there is a need to reinforce the existing, sometimes very old, cast iron columns. The paper describes a proposed and completed reinforcement procedure using an external, thin coating (sleeve or jacket) made of composite (carbon fiber reinforced polymer—CFRP). The strengthening effect was verified in destructive tests performed on two original columns (without reinforcement) and two other, identical columns strengthened by means of the proposed technique. Due to the expected very high load capacity of the axially loaded column, the test rig was designed to allow the application of the force on a big eccentricity. For this purpose a special base was designed and fabricated. Destructive tests have confirmed the high effectiveness of the adopted strengthening technique. The main objective of the present paper is a numerical confirmation of experimental results. All material parameters required in the numerical model were determined in laboratory tests. Simulation was performed using the finite element method—based on two systems, COSMOS/M and Simulia Abaqus. Numerical models were validated on results of the analytical assessment of stresses presented in the paper as well. Results of numerical simulations made on nonlinear models were compared with the experimental results. Destruction mechanisms observed in the experiments were confirmed in performed numerical simulations.

α-Amylase Inhibition, Antioxidant Activity and Phytochemical Analysis of Calotropis gigantea (L.) Dryand

Introduction: Antioxidant and α-Amylase inhibitory activity of methanolic extract of Calotropis gigantea (L.) Dryand leaves were evaluated. Methods: The antioxidant activity was evaluated by DPPH assay. The extract was fractionated in Silica gel loaded column chromatography (CC). All fractions were evaluated for their purity by TLC. Out of 11 fractions from CC, one fraction was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Results: The antioxidant activity of methanolic extract was found satisfactory (IC50268.80 µg/ml) as compared with ascorbic acid (141.82 µg/ml). TLC of a fractions showed a compound at Rf value at 0.45 in toluene: chloroform: methanol with mobile phase ratio 7:2:1 respectively. Conclusions: Total 17 compounds were identified by GC-MS of ethyl acetate fraction and 5-hydroxyl methyl furfural was major furan compound (59.49%). α-Amylase inhibitory activity of the same fraction showed IC50 value of 0.94 mg/ ml. The Nepalese originated C. gigentea (L.) Dryand possesses antioxidant and α-Amylase inhibitory property.

Optimum Design of Reinforced Concrete Columns

In the design of reinforced concrete (RC) columns, ductility is provided by allowing yielding of steel in the part of section under tensile stresses. This situation cannot be provided for RC columns since sections of columns are generally under compressive stresses resulting from axial loading including weight of all upper stories, flexural moments, and shear forces. To practically provide ductility, axial force is limited, and stirrups are densely designed. These rules are given in design regulations and must be checked during optimization. In this chapter, an optimum design methodology for biaxial loaded column is presented. Uniaxial loaded column methodology is given with the computer code. Finally, the slenderness effects are presented via ACI 318: Building code requirements for structural concrete and optimum results are given for several numerical cases using various metaheuristic algorithms.

A Process for the Recovery of Gallium from Gallium Arsenide Scrap

The recovery of gallium (Ga) from gallium arsenide (GaAs) scrap using a leaching-ion exchange method was investigated. The ground GaAs scrap was leached, using 2.0 N nitric acid at 30 °C for 1.0 h, and the dissolution of Ga and arsenic (As) reached 98%. The pregnant solution with a 1/20 dilution ratio was then passed through a weak acid chelating resin Diaion CR-11. Highly charged Ga3+ has the ability to form complexes with the chelating resin and separate from the coexisting H3AsO4 in the leachate with very low pH. The loaded column was eluted with 0.1 M H2SO4, and the final concentrated solution had 4.5 g/L of Ga with 99.3% purity. The effluent from the column was further processed to remove As by ferric arsenicate precipitation, and reused continuously as the dilution water for raw leachate.