This paper introduces experimental results of eighteen simply supported reinforced concrete beams of cross sections ( ) and length 3000 mm to study the effect of lacing reinforcement on the performance of such beams under static and fatigue loads. Twelve reinforced concrete beams (two of them are casted with vertical shear reinforcement used as control beams) are tested under four points bending loading with displacement control technique and six laced reinforced concrete beams were exposed to high frequency (10 Hz) by fixing the fatigue load in each cycle. Three parameters are used in the designed beams, which are: lacing bar diameter (4mm, 6mm, and 8mm), lacing bar inclination angle to horizontal , and lacing steel ratio depending on number of lacing bar in each longitudinal face of beam and lacing bar diameter. The comparison results of experimental tests revealed that the ultimate loads of laced reinforced concrete beams are higher than the conventional reinforced concrete beams due to increasing lacing bar diameter, angle of inclination lacing bar, and lacing steel ratio, while the deflection is reduced. Also, the laced reinforced concrete beams can safely withstand the fatigue loading.
In this work, the behavior of reinforced concrete columns under biaxial bending is studied. This work aims at studying the strengthening of columns by using carbon fiber reinforced polymer (CFRP). The experimental work includes investigation of eight reinforced concrete columns (150*150*500mm) tested under several load conditions. Variables considered in the test program include; effect of eccentricity and effect of longitudinal reinforcement (Ø12mm or Ø6mm). Test results are discussed based on load – lateral deflection behavior, load –longitudinal deflection behavior, ultimate load and failure modes. The CFRP reinforcement permits
a complete change in the failure mode of the columns .The effect of longitudinal reinforcement in
Abstract
Documentary credits are considered successful means to reduce imports, especially unnecessary imports that lead to the outflow of foreign currency from the country. However, due to the backwardness of the banking methods, the reintroduction of documentary credits after 2003 did not effectively contribute to reducing import rates. This has had a negative impact on the Iraqi economy and made it vulnerable to external markets. Documentary credits are also considered the best way to ensure payment in international trade, providing independent credit support and sufficient security for exporters and importers against commerci
... Show MoreIsrael is one of the countries most interested in Iran's nuclear program file, and the progress of negotiations between Iran and the six countries and will end it, as well as the nature of the relationship between Iran and the United States of America. Is determined by the Israeli vision of the nature of Iran's nuclear program Iran's policy toward Israel orientations, which does not recognize the existence of Israel. Israel, therefore, one of the countries pushing to prevent Iran from acquiring nuclear technology. However, those Israeli efforts did not succeed in achieving its objectives, the United States of America and European countries is well aware of the risk of stenosis on Iran, as well as the risks and the consequences of militar
... Show MoreIn engineering, the ground in seismically active places may be subjected to static and seismic stresses. To avoid bearing capacity collapse, increasing the system's dynamic rigidity, and/or reducing dynamic fluctuations, it may be required to employ deep foundations instead of shallow ones. The axial aptitude and pipe pile distribution of load under static conditions have been well reported, but more study is needed to understand the dynamic axial response. Therefore, this research discusses the outputs of the 3D finite element models on the soil-pile behavior under different acceleration intensities and soil states by using MIDAS GTS NX. The pipe pile was represented as a simple elastic, and a modified Mohr-Coulomb mode
... Show MoreThe main objective of this research is to design and select a composite plate to be used in fabricating wing skins of light unman air vehicle (UAV). The mechanical properties, weight and cost are the basis criteria of this selection. The fiber volume fraction, fillers and type of fiber with three levels for each were considered to optimize the composite plate selection. Finite element method was used to investigate the stress distribution on the wing at cruise flight condition in addition to estimate the maximum stress. An experiments plan has been designed to get the data on the basis of Taguchi technique. The most effective parameters at the process to be find out by employing L9
... Show MoreThe AlAdhaim Dam is located 133 kilometers northeast of Baghdad. It is a multipurpose dam and joints the Iraqi dam system in 2000. It has a storage capacity of 1.5 billion m3. The dam has an ogee spillway with a length of 562 m, a crest level of 131.5 m.a.m.s.l. and a maximum discharge capacity of 1150 m3/s at its maximum storage height of 143 m.a.m.s.l. This research aimed to investigate the hydrodynamics performance of the spillway and the stilling basin of AlAdhiam Dam by using numerical simulation models under gated situations. It was suggested to modify the dam capacity by increasing the dam's storage capacity by installing gates on the crest of the dam spillway. The FLUENT program was used to
... Show MoreRoller compacted concrete (RCC) is a concrete compacted by roller compaction. The concrete mixture in its unhardened state must support a roller while being compacted. The aim of this research work was to investigate the behavior and properties of roller compacted concrete when constructed in the laboratory using roller compactor manufactured in local market to simulate the field conditions. The roller compaction was conducts in three stages; each stage has different loading and number of passes of the roller. For the first stage, a load of (24) kg and (5) passes in each direction had been employed. For the second stage, a load of (104) kg and (10) passes in each direction were conducted. Finally, at the third stage, a load of (183) kg a
... Show MoreThis research presents and discuss the results of experimental investigation carried out on geogrids model to study the behavior of geogrid in the loose sandy soil. The effect of location eccentricity, depth of first layer of reinforcement, vertical spacing, number and type of reinforcement layers have been investigated. The results indicated that the percentage of bearing improvement a bout (22 %) at number of reinforced layers N=1 and about (47.5%) at number of reinforced layers N=2 for different Eccentricity values when depth ratio and vertical spacing between layers are (0.5B and 0.75B) respectively