Columns subjected to pure axial load rarely exist in practice. Reinforced concrete columns are usually subjected to combination of axial and lateral actions and deformations, caused by spatially‐complex loading patterns as during earthquakes causes lateral deflection that in turn affects the horizontal stiffness. In this study, a numerical model was developed in threedimensional nonlinear finite element and then validated against experimental results reported in the literatures,
to investigate the behavior of conventionally RC columns subjected to axial load and . lateral reversal cyclic loading. To achieve this goal, numerical analysis was conducted by using finite element program ABAQUS/Explicit. The variables considered in this study were axial load index, concrete compressive strength, column aspect ratio, longitudinal and transverse reinforcement ratios. According to numerical case studies, the results revealed that axial load index and longitudinal reinforcement ratio have the most impact on the column response. Also, increasing concrete compressive strength and reducing column aspect ratio resulted in increasing strength capacity of the column. Moreover, increasing lateral confinement by transverse reinforcement at the column ends increases the flexural strength of a flexure-controlled RC columns.
Abstract
This study is aim to :
- Put a standard to evaluate the altruistic behavior in kindergarten children.
- Know level of the altruistic behavior in the kindergarten children according to their mother "s points of view.
- Know the level of the altruistic behavior in the kindergarten children according to their teacher "s points of view.
- The differences in the level of altruistic behavior in kindergarten children between their mothers & teachers points of view.
The sample consists of (120) children of kindergarten children in Baghdad. The researcher has built a to
... Show MoreThe dispersion relation of linear quantum ion acoustic waves is derivate according to a fluid approach that depends on the kinetic description of the systems of charged particles model. We discussed the dispersion relation by changing its parameters and graphically represented. We found through graphs that there is full agreement with previous studies on the subject of interest. That motivates us to discuss the dispersion relation of waves depending on the original basic parameters that implicitly involved in the relationship which change the relationship by one way or another, such as electron Fermi temperature and the density at equilibrium state.
Rapid worldwide urbanization and drastic population growth have increased the demand for new road construction, which will cause a substantial amount of natural resources such as aggregates to be consumed. The use of recycled concrete aggregate could be one of the possible ways to offset the aggregate shortage problem and reduce environmental pollution. This paper reports an experimental study of unbound granular material using recycled concrete aggregate for pavement subbase construction. Five percentages of recycled concrete aggregate obtained from two different sources with an originally designed compressive strength of 20–30 MPa as well as 31–40 MPa at three particle size levels, i.e., coarse, fine, and extra fine, were test
... Show MoreBackground: The aim of this study was to evaluate the effect of thermo cycling and different pH of artificial saliva (neutral, acidic, basic) on impact and transverse strength of heat cure acrylic resin reinforced of with 5% silanated ZrO2 nano fillers. Materials and methods: 120 samples were prepared, 60 samples for impact strength test and another 60 samples for transverse strength test, for each test, samples were divided into two major groups (before and after thermo cycling), then each of these major groups were further subdivided into 3 subgroups according to the pH of prepared artificial saliva (neutral, acidic, basic). Charpy impact device was used for impact strength test and Flexural device was used for transverse strength test. R
... Show MoreThe aim of this study was to assess the nutritional status for samples at the age of 17-15 years. These samples were taken from secondary schools and universities in Baghdad area, 123 of them were male and 261 were female. Data on weight, height and body mass index (BMI) were determined in each individual. Smaller sample of 215 individuals (male and female) from the original sample was taken in order to record their nutritional behavior and daily food intake during the 24 hours prior to the visit through personal meeting using special questionnaire. The results showed that the weight and the height were within the range of the people of neighboring Arab countries, who are in the same age. Beside 44.4- 55.95% of these samples were within t
... Show MoreIn this paper, an ecological model with stage-structure in prey population, fear, anti-predator and harvesting are suggested. Lotka-Volterra and Holling type II functional responses have been assumed to describe the feeding processes . The local and global stability of steady points of this model are established. Finally, the global dynamics are studied numerically to investigate the influence of the parameters on the solutions of the system, especially the effect of fear and anti-predation.
The cement slurry is a mixture of cement, water and additives which is established at the surface for injecting inside hole. The compressive strength is considered the most important properties of slurry for testing the slurry reliability and is the ability of slurry to resist deformation and formation fluids. Compressive strength is governed by the sort of raw materials that include additives, cement structure, and exposure circumstances. In this work, we use micro silica like pozzolanic materials. Silica fume is very fine noncrystalline substantial. Silica fume can be utilized like material for supplemental cementations for increasing the compressive strength and durability of cement. Silica fume has very fine particles size less
... Show MorePolymer electrolyte films composed of PVP and PVP/glycerin with varying concentrations of CuCl2 (10, 20, and 30 wt.%) were synthesized using the solution casting method. The synthesized electrolyte films were characterized using FTIR, XRD, UV-Vis, DSC, and TGA techniques. FTIR spectroscopy revealed an O-H stretching vibration of PVP around 3300 cm(-1), which experienced broadening and a reduction in intensity upon the introduction of glycerin and CuCl2. XRD analysis displayed a characteristic peak at 2 theta similar to 20 degrees, with the peak shifting towards higher angles and a slight decrease in intensity as the CuCl2 concentration increased, indicating a disruption of the crystalline structure of the host matrix. UV-Vis analysis reveal
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