The clayey soils have the capability to swell and shrink with the variation in moisture content. Soil stabilization is a well-known technique, which is implemented to improve the geotechnical properties of soils. The massive quantities of waste materials are resulting from modern industry methods create disposal hazards in addition to environmental problems. The steel industry has a waste that can be used with low strength and weak engineering properties soils. This study is carried out to evaluate the effect of steel slag (SS) as a by-product of the geotechnical properties of clayey soil. A series of laboratory tests were conducted on natural and stabilized soils. SS was added by 0, 2.5, 5, 10, 15, and 20% to the soil. The conducted tests are consistency limits, specific gravity, hydrometer analysis, modified Proctor compaction, swelling pressure, swelling percent, unconfined compressive strength, and California Bearing Ratio (Soaked CBR). The results showed that the values of liquid limit, plasticity index, optimum moisture content, swelling pressure, and swelling percent were decreased when stabilized the soil. However, the values of maximum dry density, unconfined compressive strength, and California bearing ratio were increased with the addition of steel slag with various percentages to the clayey soil samples. The steel slag was found to be successfully improving the geotechnical properties of clayey soils.
he paper presents the results of exposure of normal concrete to high temperatures (400 and 700°C). In addition to the exposure of steel reinforcement bar Ø 12 mm, where two types of steel reinforcement burning situations were performed. Directly exposed to high temperatures (400 and 700°C) and others were covered by concrete layer (15 mm). From the experimental results of fire exposure for 1 hour of 400 and 700°C and gradually cooled, it was found that the residual average percentage of compressive strength of concrete was 85.3 and 41.4%, while the residual average percentage of modulus of elasticity of concrete was 75 and 48%, respectively. The residual average percentage of yielding tensile stress (Ø 12 mm) after burning and cooling
... Show MoreLaser beam has been widely used to improve the mechanical properties of the metals. It used for cutting, drilling, hardening, welding……etc. The use of Laser beam has many features in accuracy and speeding in work, also in the treatment of metals locally, and in the places that is hard to reach by traditional ways. In this research a surface treatment was done to medium carbon steel (0.4%C) which is common kind of steel that is used in industry. Pulsing Neodymium -YAG Laser has been used and 1.06 micrometer wave length and 5 msec and the distance is about 30 centimeter between the exit area of the Laser beam from the system and the piece that treated . We are going to check the fatigue resistance for samples that is
... Show MoreIn this paper, the behavior of spliced steel girders under static loading is investigated. A group of seven steel I-girders were tested experimentally. Two concentrated loads were applied to each specimen at third points and the load was increased incrementally up to the yield of the specimen. Two types of splices were considered; the bearing type and the friction-grip type splices. For comparison, an analytical study was made for the tested girders in which the finite element analysis program (Abaqus) was used for analysis. It was found that the maximum test load for spliced girders with bearing type splices was in the range of (34%) to (67%) of the maximum test load for the reference girder. For girders spliced by using friction-grip t
... Show MoreSteel-concrete-steel (SCS) structural element solutions are rising due to their advantages over conventional reinforced concrete in terms of cost and strength. The impact of SCS sections with various core materials on the structural performance of composites has not yet been fully explored experimentally, and in this work, both slag and polypropylene fibers were incorporated in producing eco-friendly steel-concrete-steel composite sections. This study examined the ductility, ultimate strength, failure modes, and energy absorption capacities of steel-concrete-steel filled with eco-friendly concrete, enhanced by polypropylene fiber (PPF) to understand its impact on modern structural projects. Eco-friendly concrete was produced by the partial
... Show MoreThis paper investigates the interaction between fiscal and monetary policy in Iraq after 2003 using the prisoner’s dilemma.The paper aims to determine the best form of coordination between these policies to achieve their goals; payoff matrix for both policies was constructed. To achieve the purpose, the quantitative approach was applied using several methods, including regression, building payoff matrices and decision analysis using a number of software.The results of the monetary policy payment function show that inflation rate has an inverse relationship with the auctions of selling foreign currency and a positive relationship with the government’s activity, while the fiscal policy function shows that real growth is positively
... Show MoreIn this search, a new bioluminescent technique was proved for pyrophosphate which was employed to single- nucleotide polymorphism (SNP) diagnosis using one-base extension reaction. Four Mycobacterium tuberculosis genes were chosen (Rpob, InhA, KatG, GyrA) genes. Fifty-four specimens were used in this study fifty-three proved as drug-resistant specimens by The Iraqi Institute of Chest and Respiratory Diseases in Baghdad., also one specimen was used as a negative control. The procedure of this assay was as follows. A specific primer within each aliquot owning a short 3-OH end of the base of the target gene was hybridized to the single-stranded DNA template. Then, (exo-) Klenow DNA polymerase and one of either ?-thio-dATP, dTTP, dGTP, or dCTP
... Show MoreIn this research, the one of the most important model and widely used in many and applications is linear mixed model, which widely used to analysis the longitudinal data that characterized by the repeated measures form .where estimating linear mixed model by using two methods (parametric and nonparametric) and used to estimate the conditional mean and marginal mean in linear mixed model ,A comparison between number of models is made to get the best model that will represent the mean wind speed in Iraq.The application is concerned with 8 meteorological stations in Iraq that we selected randomly and then we take a monthly data about wind speed over ten years Then average it over each month in corresponding year, so we g
... Show MoreThis study aims to use claystone beds exposed in the Injana Formation (Late Miocene) at Karbala-Najaf plateau, middle of Iraq for the manufacturing of perforated and ordinary bricks. The claystone samples were assessed as an alternative material of the recent sediments, which are preferred to remain as agricultural land. The claystones are sandy mud composing of 29.1 - 39.1% clay, 37.2 - 54.8% silt and 14.1-26.8% sand. They consist of kaolinite, illite, chlorite, palygorskite, and montmorillonite with a lot of quartz, calcite, dolomite, gypsum and feldspar. Claystone samples were characterized by linear shrinkage 0.01 - 0.1%, volume shrinkage 0.1 - 0.9%, bulk density 1.2 - 2.11gm/cm3 (1.68 g / cm3 average), and the efflorescence is
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