In this paper, mesoscale modeling is performed to simulate and understand fracture behavior of two concrete composites: cement and asphalt concrete using disk-shaped compact tension (DCT) tests. Mesoscale models are used as alternative to macroscale models to obtain better realistic behavior of composite and heterogeneous materials such as cement and asphalt concrete. In mesoscale models, aggregate and matrix are represented as distinct materials and each material has its characteristic properties. Disk-shaped compact tension test is used to obtain tensile strength and fracture energy of materials. This test can be used as a better alternative to other tests such as three points bending tests because it is more convenient for both field and laboratory specimens in addition to its accurate results. Comparing the numerical results of the mesoscale models of cement and asphalt concrete specimens with experimental data shows that these models can predict the behavior of these composite materials very well as seen in the curves of load-crack mouth opening displacement (CMOD). Also, the mesoscale modeling highlights the variability of crack direction where it is dependent on the random distribution of aggregate.
Infrastructure projects take a long time, are complex, multidisciplinary, use different materials and products, and have high risk. These characteristics affect the process of supplying materials. The current paper studies the ability to improve the supply chain process and decrease its cost by identifying the factors that affect it. These factors are used as variables in the mathematical model, which is working under uncertain conditions when the consumption rate of materials is not constant. The information used in this model is obtained from Building Information Modeling (BIM) and Geographical Information System (GIS) techniques and the genetic algorithm is utilized to determine the optimal supplier and the quantities of supplies
... Show MoreThe world is moving towards greening business in general and production systems in particular. At the same time, economic units seek to enhance their productivity and find any variables that can contribute to improving their elements. Economic units should not ignore the green dimension of cost management techniques because of its role in containing the green dimension of the production system and the product. However the few researches dealt with the subject of the green kaizen showed its role in reducing costs and improving the environment. Those researches did not address its contribution to raising the level of productivity. Productivity is an important indicator of economic units that expresses their level of success and progre
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Flooding hazard is an important and dangerous natural phenomenon that leads to significant material losses. It should be studied and scenario to prevent significant losses. The studies should consider the impact of many factors such as human, infrastructure, economic,..etc. The main objective of the research is the risk management procedure. The study was conducted in Baghdad, Iraq. The materials for completing this research were prepared by gathering a satellite image and Digital Elevation Model (DEM) via the USGS website, then processed, analyzed, and converted into a different flood region concerning the probability of rising water levels where the normal height of Baghdad city is 28m over sea level. This scenario defines 3m,
... Show MoreOur research addresses one of the aspects of nostalgia for one of the most well-known Israeli writers of Iraqi origin (Sami Michael) who spent his childhood in Baghdad. The Israeli government has also been forced to emigrate with its family as a result of the Zionist propaganda that the Zionist institutions have followed since the early decades of this century in the Arab unrest and massacres. The fact that the homeland is like a mother is A fact that is compelling and something of an expatriate human being; the homeland is a fact that remains in the person's consciousness to be the image of the mother: The lover, love, safety, identity. The language that is formulated, and the memories that make its past, present and future, are all concep
... Show MoreOne hundred and seventy-six cases of suspected meningitis (SMN) were included in a cross-sectional study. Their ages ranged from less than 1 year to 80 years, of whom 44.3% were male. The aim was to assess bacterial meningitis (BMN) in terms of incidence and types of causative bacteria. Cerebrospinal fluid (CSF) specimens were collected and polymerase chain reaction (PCR) analysis was conducted with universal primers designed to amplify a DNA fragment (996 bp) of the 16S rRNA gene of eubacteria. Resolving PCR products in agarose-gel electrophoresis revealed that 37.5% of CSF specimens were PCR positive, while 62.5% of CSF specimens showed no band and were considered PCR-negative. Eighty percent of the latter specimens were not
... Show MoreThere are many events which causes nonproductive time (NPT) in the drilling industry. The mostly effective in this NPT is pipe sticking event. A considerable amount of time and resources can be spent in efforts to free a stuck pipe. In addition, Unsuccessful fishing operations results in costly alternatives including side-tracking. The drilling in Khabaz oil field poses many operational challenges among of them stuck pipe , lost circulation, flow of salt water during drilling, and hole caving. Stuck pipe can be considered the quite difficult problem in Khabaz oil field due to associated incidents which lead to NPT activities.
Well Khabaz -34 was selected to study the problem of stuck pipe in this field. An analysis of stuck pipe event