In this paper, a dynamic investigation is done for strip, rectangular and square machine foundation at the top surface of two-layer dry sand with various states (i.e., loose on medium sand and dense on medium sand). The dynamic investigation is performed numerically using finite element programming, PLAXIS 3D. The soil is expected as a versatile totally plastic material that complies with the Mohr-Coulomb yield criterion. A harmonic load is applied at the base with an amplitude of 6 kPa at a frequency of (2 and 6) Hz, and seismic is applied with acceleration – time input of earthquake hit Halabjah city north of Iraq. A parametric study is done to evaluate the influence of changing L/B ratio (Length=12,6,3 m and width=3 m), type of sand, and frequency of the machine for soil with two layers (dense and medium sand) and (loose and medium sand). It was noticed that the displacement decreases when the foundation is strip, and has the highest values when the foundation is square. At the same time, the maximum vertical stress of the foundation (L/B = 4 and L/B = 1) appears to be (1262) kPa and (1255) kPa, respectively, due to increasing the foundation mass as a result of increasing its dimensions. Then again, the displacement increases by 20% for vertical displacement when decreasing the relative density. In addition, it has been noticed that there is a decrease in displacement when the frequency value changes from (2 to 6) Hz.
Since seismic reflection data produce comprehensive subsurface images that reveal geological structures likely to contain minerals, oil, and gas, they are essential for resource exploitation. When paired with well logs, these data enable seismic and petrophysical assessments that lower drilling risks and boost efficiency. Wireline logs from five wells and seismic coverage of the Nasiriyah oil field (Dhi-Qar Governorate), processed with Schlumberger software, were used to characterize the Yamama reservoir. Synthetic seismograms connected reservoir tops to seismic data; however, resistivity and gamma logs helped with correlation and sequence delineation. Wells' correlation described the migration routes of hydrocarbons and reservoir c
... Show MoreA study of some mite species of alfalfa. wheat, and barley was conducted in central Iraq.
The mites were extracted using a tullgren funnel method. Twelve species were recorded. 10 of
them belong to suborder Trombidiformes and 2 belong to suborder Sarcoptiforms. Three
mites, Irnpar(pes hystricinus, Scutacarus longitarsus, and Rhizoglyphus echin opus are new
records for Iraqi mite fauna, and 11 are new host records in alfalfa soil.
Fluid-structure interaction method is performed to predict the dynamic characteristics of axial fan system. A fluid-structure interface physical environment method (monolithic method) is used to couple the fluid flow solver with the structural solver. The integration of the three-dimensional Navier-Stokes equations is performed in the time Doman, simultaneously to the integration of the three dimensional structural model. The aerodynamic loads are transfer from the flow to structure and the coupling step is repeated within each time step, until the flow solution and the structural solution have converged to yield a coupled solution of the aeroelastic set of equations. Finite element method is applied to solve numerically
... Show MoreConstruction joints serve as interruption points in the concrete placement process, which is necessary because it is often not feasible to pour concrete continuously in many structures. The quantity of concrete that can be poured at a single instance depends on the batching and mixing capacity, as well as the strength of the formwork. An effective construction joint must ensure sufficient flexural and shear continuity across the junction. Many studies investigated the construction joints in the reinforced concrete (RC) normal beams, but there are no studies investigating the effect of construction joints on the behavior of the RC deep beams. This study was prepared to show the behavio
Frequency equations for rectangular plate model with and without the thermoelastic effect for the cases are: all edges are simply supported, all edges are clamped and two opposite edges are clamped others are simply supported. These were obtained through direct method for simply supported ends using Hamilton’s principle with minimizing Ritz method to total energy (strain and kinetic) for the rest of the boundary conditions. The effect of restraining edges on the frequency and mode shape has been considered. Distributions temperatures have been considered as a uniform temperature the effect of developed thermal stresses due to restrictions of ends conditions on vibration characteristics of a plate with different
... Show MoreConcrete pavements are essential to modern infrastructure, but their low tensile and flexural strengths can cause cracking and shrinkage. This study evaluates fiber reinforcement with steel and carbon fibers in various combinations to improve rigid pavement performance. Six concrete mixes were tested: a control mix with no fiber, a mix with 1% steel fiber (SF1%), a mix with 1% carbon fiber (CF1%), and three hybrid mixes with 1% fiber content: 0.75% steel /0.25% carbon fiber (SF0.75CF0.25), 0.25% steel /0.75% carbon fiber (SF0.25CF0.75), and 0.5% steel /0.5% carbon fiber ((SF0.5CF0.5). Laboratory experiments including compressive, flexural, and splitting tensile strength tests were conducted at 7, 28, and 90 days, while Finite Element Analys
... Show MoreThe influence and hazard of fire flame are one of the most important parameters that affecting the durability and strength of structural members. This research studied the influence of fire flame on the behavior of reinforced concrete beams affected by repeated load. Nine self- compacted reinforced concrete beams were castellated, all have the same geometric layout (0.15x0.15x1.00) m, reinforcement details and compressive strength (50 Mpa). To estimate the effect of fire flame disaster, four temperatures were adopted (200, 300, 400 and 500) oC and two method of cooling were used (graduated and sudden). In the first cooling method, graduated, the tested beams were leaved to cool in air while in the second method, sudden, water splash was use
... Show MoreCeramics type Yttrium oxide with Silicon carbide. were selected to investigate its sintered density, microstructure and electrical properties, after adding V2O5, of 100 nm grain size. Different weight percentages ranging from (0.01,0.02,0.03 and 0.04) were used. Dry milling applied for twelve hours. The pelletized samples were sintered at atmospheric of static air and at sintering temperature 1400 ˚C, for three hours. The crustal structure test shoes the phase which is yttrium silicon carbide Scanning electron microscopy, scan sintered microstructure. Samples after sintering were electrically investigated by measuring its capacitance, dielectric constant and their results showed increasing after added V2O5 particles at the combinat
... Show MoreThe influence and hazard of fire flame are one of the most important parameters that affecting the durability and strength of structural members. This research studied the influence of fire flame on the behavior of reinforced concrete beams affected by repeated load. Nine self- compacted reinforced concrete beams were castellated, all have the same geometric layout (0.15x0.15x1.00) m, reinforcement details and compressive strength (50 Mpa).
To estimate the effect of fire flame disaster, four temperatures were adopted (200, 300, 400 and 500) oC and two method of cooling were used (graduated and sudden). In the first cooling method, graduated, the tested beams were leaved to cool in air while in the seco
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