In this paper, a shallow foundation (strip footing), 1 m in width is assumed to be constructed on fully saturated and partially saturated Iraqi soils, and analyzed by finite element method. A procedure is proposed to define the H – modulus function from the soil water characteristic curve which is measured by the filter paper method. Fitting methods are applied through the program (SoilVision). Then, the soil water characteristic curve is converted to relation correlating the void ratio and matric suction. The slope of the latter relation can be used to define the H – modulus function. The finite element programs SIGMA/W and SEEP/W are then used in the analysis. Eight nodded isoparametric quadrilateral elements are used for modeling both the soil skeleton and pore water pressure. A parametric study was carried out and different parameters were changed to study their effects on the behavior of partially saturated soil. These parameters include the degree of saturation of the soil (S) and depth of water table. The study reveals that when the soil becomes partially saturated by dropping water table at different depths with different degrees of saturation, the bearing capacity of shallow foundation increases about (4 – 7) times higher than the bearing capacity of the same soil under saturated conditions. This result is attributed to matric suction value (i.e negative pore water pressure). The behavior of soil in partially saturated condition is like
that of fully saturated condition but with smaller values of displacement. It is found that the settlement is reduced when the water table drops to a depth of 2 m (i.e. twice the foundation width) by about (92 %).
Recently, wireless communication environments with high speeds and low complexity have become increasingly essential. Free-space optics (FSO) has emerged as a promising solution for providing direct connections between devices in such high-spectrum wireless setups. However, FSO communications are susceptible to weather-induced signal fluctuations, leading to fading and signal weakness at the receiver. To mitigate the effects of these challenges, several mathematical models have been proposed to describe the transition from weak to strong atmospheric turbulence, including Rayleigh, lognormal, Málaga, Nakagami-m, K-distribution, Weibull, Negative-Exponential, Inverse-Gaussian, G-G, and Fisher-Snedecor F distributions. This paper extensive
... Show MoreSolvents are important components in the pharmaceutical and chemical industries, and they are increasingly being used in catalytic reactions. Solvents have a significant influence on the kinetics and thermodynamics of reactions, and they can significantly change product selectivity. Solvents can influence product selectivity, conversion rates, and reaction rates. However, solvents have received a lot of attention in the field of green chemistry. This is due to the large amount of solvent that is frequently used in a process or formulation, particularly during the purification steps. However, neither the solvent nor the active ingredient in a formulation is directly responsible for the reaction product's composition. Because these ch
... Show MoreThe digital camera which contain light unit inside it is useful with low illumination but not for high. For different intensity; the quality of the image will not stay good but it will have dark or low intensity so we can not change the contrast and the intensity in order to increase the losses information in the bright and the dark regions. . In this search we study the regular illumination on the images using the tungsten light by changing the intensities. The result appears that the tungsten light gives nearly far intensity for the three color bands(RGB) and the illuminated band(L).the result depend on the statistical properties which represented by the voltage ,power and intensities and the effect of this parameter on the digital
... Show MoreCarbon fibre reinforced polymers are widely used to strengthen steel structural elements. These structural elements are normally subjected to static, dynamic and fatigue loadings during their life-time. A number of studies have focused on the characteristics of CFRP sheets bonded to steel members under static, dynamic and fatigue loadings. However, there is a gap in understanding the bonding behaviour between CFRP laminates and steel members under impact loading. This paper shows the effect of different load rates from quasi-static to 300 × 103 mm/min on this bond. Two types of CFRP laminate, CFK 150/2000 and CFK 200/2000, were used to strengthen steel joints using Araldite 420 epoxy. The results show a significant bond strength enhancemen
... Show MoreIn this study, the concentrations of uranium for four species of plants; Spinacia, Brassica Oleracea, BEASSICA Oleracea Var Capitata and Beta Vulgaris were measured in addition to the measurement of uranium concentrations in the selected soil by calculating the number of significant traces of alpha in CR-39. The 2.455 Bq/kg in Spinacia plant were the highest concentration while the lowest concentration of uranium were 1.91 Bq/kg in BEASSICA Oleracea Var Capitata plant. As for the transfer factor, the highest value 0.416 were found in Spinacia plant and the lowest value 0.323 were found in BEASSICA Oleracea Var Capitata plant. The uranium in the models studied in it did not exceed the international limit, according to the International Atomi
... Show MoreUltrasonic Extraction method followed by gradient HPLC was carried out for the simultaneous determination of four insecticides are [imidacloprid (Imi), thiamethoxam (Thi), indoxacarb (Ind) and abamectin (Aba)] used to combat the major insect pests in Iraq, whitefly, Dubas Bug, worms fruits as well as to combat the spiders – dream respectively in eco-soil samples. The extraction recovery was in the range of 99.77 to 109.1 %. The dissipation kinetics and residual levels of these insecticides in soil sample was studied under field ecosystem. The half-life of the mix insecticides was determined. The half-life was in range of 0.38 to 4.06 days with the soil samples were brought from the Agricultural Land called Nahrawan located in th
... Show MoreThe current study was conductedas a pot experiment to determine the effect of soil texture on biological nitrogen fixation (BNF) of six most efficient local isolates, specified, of Bradyrhizobium. Cowpea (Vignaunguiculata L.), as a legume host crop, was used as a host crop and 15N dilution analysis was used for accurate determination of the amount of N biologically fixed under experimental parameters specified. Soils used are clay loam, sandy clay loam and sandy loam. Biological Nitrogen Fixation (BNF), in different soil textural classes, was as in the following order: medium texture soil > heavy texture soil > light textured soil. Statistical analysis showed that there is a significant variation in BNF % among six Iraqi isolates in the th
... Show MoreThe antagonism of the rhizospheric bacteria toward pathogenic fungi Macrophomina phaseolina was investigated. Ten soil samples were collected from the rhizospheric zone around Cowpea root (Vignaunguiculata L.). These samples were used as the source of Arbuscular Mycorrhizal fungi (AMF) and rhizobacterial isolates. Twenty-five bacteria were isolated and evaluated as an antagonistic agent against pathogenic fungi. M. phaseolina was isolated from infected roots of Cowpea and used as a pathogen. Twenty-five bacteria were isolated and evaluated as an antagonistic agent against pathogenic fungi. M. phaseolina was isolated from infected roots of Cowpea and used as a pathogen. The synergistic effect between A. siccitolerans and (AMF) Glomusmosseae,
... Show MoreBacterial strains were isolated from oil-contaminated soil, in 2018, these isolates were identified, and with the aim of finding out the ability of these isolates to degrede the oil compounds, the color change of medium which added to it isolates was read by the method of Pacto Bushnell Hans. Then the change in the petroleum compounds was read by gas chromatography, for the most effective isolates.
The nine isolated bacterial showed different degrees of color change, and the isolates (Pseudomonas, Bacillus, Micrococcus) outperformed the color change amount (78, 78, 77) %, respectively, compared to the control, and the three isolates together showed the best color change of 90.7. % Compared to the control, and the
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