Reinforced concrete slabs are one of the most important and complicated elements of a building. For supported edges slabs, if the ratio of long span to short span is equal or less than two then the slab is considered as two-way slab otherwise is consider as one-way slab. Two-way reinforced concrete slabs are common in use in reinforced concrete buildings due to geometrically arrangement of columns suggested by architects who prefer a symmetric distribution of columns in their plans. Elastic theory is usually used for analysis of concrete slabs. However, for several reasons design methods based on elastic principles are limited in their function. Correspondingly, limit state analysis offers a powerful technique for considering such matter. The Yield Lines Theory, which is one of limit state analysis based on expected failure criteria of slabs. The assumed failure criteria is termed by a pattern of yield lines, along that the reinforcement has yielded and the location of which counts loads and boundary conditions. This paper deals with comparison of Method 3 for two-way slabs that was provided by the ACI Code and exact derivation of this method by the Yield Lines Theory. Total of nine cases of slabs that have been described by method three are studied and evaluated by plastic analysis assumptions of the yield lines theory. The results are summarized in terms of proposed formulae that derived according to the Yield Lines Ttheory, which could be used as an alternative method for design of two-way reinforced concrete slabs in the ACI Code.
The use of the entrance diffraction hexagon continuous improvement of operations in order to achieve the rationalization of activities, costs and efficiency in the use of available resources and reduce the incidence of damage and waste and recycling, as the accounting information system does not meet the surface production processes oil fields cost management requirements in the measurement and evaluation of the costs of each activity and development of indicators to evaluate the efficiency and effectiveness of production processes and to cover the shortcomings of currently approved by the company so cost accounting system has Find addressed the use of strategic cost management techniques, including the entrance diffraction hexagon for c
... Show MoreThe study aims to identify the psychological, social, and academic problems that encounter students at the college of education. To this end, the researcher utilized the descriptive approach, where a questionnaire was used as a tool to collect the study data. The findings of study revealed that the main academic problems are inability to understand what the students read, lack of concentration over the process of studying. The Difficulty of preparation for test. Lack of ability to memorize quickly. As for the prominent social problems: the excessive usage of social media that drove students away from their main tasks, the Lack of participation in social activities, the scarcity the religious information. The psychological problems includ
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The experiment has been carried out in the Syrian National Commission of Biotechnology, during the growing season 2018/2019, to study the effect of abiotic stresses (salinity and osmotic stresses) on the activity of some antioxidant enzymes and biochemical traits in Catharanthus roseus. The experiment has been laid according to (CRD) with three replications. The seeds have been sterilized by NaOCl solution (0.5% v/v), then planted on MS medium. Plantlets have been moved to MS medium enriched with NAA (1 mg.L-1) and BA (2 mg.L-1). The callus has been initiated from leaves using MS medium containing NAA (1 mg L-1) and KIN (2 mg.L-1). After 60 days, callus
... Show MoreA pure posteriorly posterior communicating artery (PCoA) aneurysm represents a surgical challenge. This is mainly when there is a need for good exposure of the aneurysmal neck, sac, PCoA, and anterior choroidal arteries. Ruptured pure posteriorly directed PCoA aneurysm imposes significantly extra challenge as the surgeon undergoes dissection through a tight brain. Even with measures commonly used to attain brain relaxation like the lumbar drain and cisternal fenestration. Here, we describe a technique for posterior temporal pole mobilization (TPM) as an integrated part of microsurgical clipping of ruptured pure posteriorly directed PCoA aneurysms. This technique is implicated in twenty-three successive cases of ruptured PCoA aneurys
... Show MoreOne of the common geotechnical problems is the construction on soft soil and the improvement of its geotechnical properties to meet the design requirements. A stone column is one of the well-known techniques used to improve the geotechnical properties of soft soils. Sometimes thick layers of soft soil imposed the designer to use floating stone columns for improvement of such soil; in this case, the designer will be lost the end bearing of the stone column. In this study, the effects of several patterns of floating stone columns distribution under footing on the bearing capacity of soil and the distribution of excess porewater pressure are investigated. The soft soil used in this study has a very low undrained shear strength (cu) of
... Show MoreThis research involves study effect of chloride ions in concentration range (0.01 – 0.50 mol.dm-3) on the corrosion behavior of Al-Zn alloy in basic media of 1x10-3 mol.dm-3 NaOH at pH=11 and four different temperatures in the range (298-313 K). Cathodic and anodic Tafel slopes (bc &ba) and transfer coefficients (αc & αa) were calculated and the results interprets according to the variation of the rate – determining steps. The results also indicate that the chloride ions are bonded chemically in the interface as an initial step of formation of different mixed oxohydroxy – and chloro complexes. Polarization resistance (Rp) is calculates
... Show MoreBack ground : The transforming growth factor beta (TGFB) signaling pathway is involved in many cellular processes in both the adult organism and the developing embryo including cell growth, cell differentiation, apoptosis. The interaction between implant material and surrounding tissues is believed to play a fundamental role in implant success and illustrates different expression of growth factors by different cells that involved in the formation of peri-implant tissue. The aim of this study was to localize expression of TGF B by newly formed bone tissue around surface-conditioned implants with placental collagen at different time intervals: 3 ,7,14,28, and 56 days . Materials and Methods: Commercially pure Titanium (CPTi) implants coated w
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