bluuebunny/crossref_metadata_2025_split huggingface dataset:
Behavior and Failure Mode of GFRP bars RC Beams under Elevated Temperature
Authors: Al-Thairy Haitham , Al-hasnawi Nuha Hussien 
Published: August 2020

Abstract
The presented work is providing the results of experimental study to investigate the impact of elevated temperature on load resistance related to the concrete beams that are reinforced via the glass fibre reinforced polymers (GFRPs). There are four GFRP reinforced concrete beams with width (250mm) and height (160mm) as cross-sectional dimensions, also (1250mm) as total length have been designed according to ACI440.1R-15[1], cast using normal weight concrete and considered in the experimental tests. One specimen has been put to test at ambient temperature, while other three specimens were firstly exposed to increased temperatures (350, 500, and 600 °C), after that subjected to a monolithically increased one point load up to failure. The effect of increased temperature on load displacement relationships as well as the failure modes regarding tested beams were discussed and put to comparison with the results related to the control beam (20°C). The experimental tests results have indicated that the shear failure is the pre-dominate failure mode with regard to all the tested GFRP-beams before and after exposing to elevated temperature. Results have also shown that in comparison to the control beam (20°C), reduction in loading capacity of heated reinforced concrete beams have been 4%, 15.5% and 19% when exposing to temperature of 350°C, 500°C and 600°C respectively.
Reliable prediction of structure settlement in Al-Najaf city using laboratory testing
Authors: Mahmood M S , Almahbobi S H , Rabee A M , Rahim A M , Naama M A , Mohammed M F 
Published: August 2020

Abstract
This paper studies the effect of the specimen sizes and shapes on the settlement behaviour of sand soil with gypsum from Al-Najaf city in Iraq. The investigation aimed to verify the impact of the studied parameters of the prediction of the settlement using reliability-based analysis. Three sets of soil samples with different shapes and sizes, 60 mm diameter Oedometer cell, 60 x 60 mm box container and 100 x100 mm box container were remoulded with three different densities related to the maximum dry density, 100%, 95% and 92%. The results reveal that different settlement behaviours were determined at several normal stress levels during the soaking process. The samples exhibited reductions in volume due to the applied stresses, while under the same level of normal stress, the final settlement values due to soaking were higher for the samples with a lower value of initial relative compaction. Further, the test results showed that at any initial relative compaction and applied vertical stress, the higher settlement value is achieved by the larger square specimen (100x100)mm.
Changing bolt arrangement and their effect on bearing capacity of single shear connections
Authors: Jawad Faris A , Dheyab Hasanain M , Jasim Heydar A 
Published: August 2020

Abstract
In steel structures, bolted joints are used to connect structural elements. Due to the ease of its making, the square and rectangle arrangement of bolts are the prevalent pattern in these structural joints. To investigate the effect of changing the arrangement of bolts on the bearing capacity of single shear joint, square, circular and diamond are the patterns of bolts that have been chosen in this study. Nine specimens represent all these configurations experimentally have been tested under tension load. The results indicated that the highest bearing capacity of a single shear connection could be achieved using a square arrangement of bolts. While stresses could not be equally distributed around holes in circular and diamond pattern specimens of the same connection.
Effect of Contraction Joints on Structural Behavior of Double Curvature Concrete Dam Subject to Dynamic Loading
Authors: Khassaf Saleh Issa , Chkheiwr Aqeel Hatem , Jasim Mohammed Abdulrahim 
Published: August 2020

Abstract
A double curvature arch dam considers as complex mega structure built for the hydropower or agriculture national goals. Arch dam cost effective is less compared to other types of dams, construction a safe and stable of arch dam depending on intelligent formation of dam layouts. This work conducted to explore the structural behavior of the double curvature arch concrete dam under the variation effect of the distance in between the contraction joints. The dam blocks divided and distributed as seven intervals of the distance between the blocks of the dam as 15,17.5,20,22.5,25, 27.5, and 30 m. Stresses analysis of arch dam conducted to study the effects of these intervals on the structural behavior of double curvature concrete dam when the water in the reservoir at the operation level. Arch dam data input considered the Nonlinearity in both of dam shape and concrete materials properties to evaluate the maximum and minimum principal stresses at the top of the crown cantilever, and the maximum principal stresses along the crest path of the upstream face. Finite element and building information modeling tools (Revit – Abaqus6.13) were considered during the modeling and analysis process. The results show that the dam must be simulated for a specific interval of distance between each two contraction joints are 20 to 22.5 meter and the optimum selection to this interval of contractions joints leads to increase the structural stability status of the arch dam.
CFD Based Model to Identify the Minimum Length of a Gradual Rectangular Expansion Operated under Supercritical Flow
Authors: Hassan Fadhel A. 
Published: August 2020

Abstract
Computational Fluid Dynamics (CFD) has been used to derive a mathematical model to relate the length of a gradual expansion (Le) with the others of hydraulic and geometric parameters of the flow in rectangular channels under supercritical flow conditions. Five models with different length of expansion 30 cm, 50 cm, 75 cm, 100 cm, and 125 cm were simulated in the CFD v18.2 software and verified by experimental data which have been measured into a laboratory flume. All models of CFD software were processed depending on k – epsilon viscous models while the mesh was built by adapting the multi-zone method. Five values of inlet velocity of flow were applied in the runs of the program to each model of 1.5 m/s, 1.6 m/s, 1.7 m/s, 1.8 m/s, and 2 m/s. Depths of water along the channel were measured in multi-section, before expansion, within expansion and after expansion. The results of CFD analysis showed that the minimum length of expansion to maintain the flow within supercritical regime was 0.35 m and the ratio of (Le/W) equal to 1.167. The results of the non-dimensional relationship were compared with the experimental results and the comparison showed a significant correlation where the highest percentage difference was 13.8 %. The coefficient of determination for this equation was 0.973.
Zeolite-assisted electrocoagulation for remediation of phosphate from calcium-phosphate solution
Authors: Alenezi Ahmad K. , Hasan Hussein A. , Hashim Khalid S. , Amoako-Attah Joseph , Gkantou Michaela , Muradov Magomed , Kot Patryk , Abdulhadi Bareq 
Published: August 2020

Abstract
Phosphorus is crucial to the growth of the skeletons and the living cell. However, elevated phosphate concentrations represent a problem due to its grave impacts on human health, animal and also because of its effects on water quality and economy. This research studies the applicability of filtration-electrocoagulation (filtration - EC) system to remove phosphate from wastewater when calcium is present as competitor ions. In laboratory batch trials, the ability of zeolite filter-electrocoagulation system to eliminate phosphate from artificial wastewater samples, in the presence of calcium as competitor ions, was tested. The research was initiated by studying the ability of the electrocoagulation method (EC), as a separated treatment unit, to remove phosphate from solutions that containing calcium ions. In this phase of the study, the influence initial pH, current densities and electrolysing period. Then, the new method, filtration-EC, was applied to treat solutions (with identical chemical composition to that used in the first phase) considering the effects of the initial pH, current densities, contact periods (in the filter), electrolysing period (in the EC cell) and zeolite dosage. The results of this research evidenced that the filtration - EC system completely removes phosphate from calcium-phosphate solution at pH, current density, dosage of zeolites, contact period and electrolysing period of 7, 2.0 mA.cm−2, 150.0 g, 30.0 minutes and 20.0 minutes, respectively.
Treatment of effluents of construction industry using a combined filtration-electrocoagulation method
Authors: Alyafei Ali , AlKizwini Rasha Salah , Hashim Khalid S. , Yeboah David , Gkantou Michaela , Al Khaddar Rafid , Al-Faluji Duaa , Zubaidi Salah L. 
Published: August 2020

AbstractOne of the significant sources of water pollution is construction industry as it requires considerable freshwater amounts during manufacturing of concrete, mortars and other construction materials. Vast volume of the used water is discharged back to source of freshwater as extremely polluted effluent (high level of suspended solids and pH), which is categorized as hazardous wastewaters. Therefore, environmental regulations prevent discharging these effluents before conducting adequate treatment. As a result, efficient treatment solutions for these effluents become necessary in the field of construction industry. In this context, this research aims at treating construction industry effluents using an integrated method, which involves adsorption (AD) and electrochemical (EL) techniques, to treat effluents of concentration sites. Turbidity and chemical oxygen demand (COD) were selected as pollutants models due to their wide occurrence in this type of effluents. 200 mg of activated carbon (AC) and four aluminum electrodes were utilized to construct the adsorption and electrochemical units, respectively. Aluminum and AC were used here as they are economically efficient, safe, and have a proven efficiency in waters/wastewaters treatment. The influences of initial pH, retention time (RT) and electrolyzing time (ET) on the removal of COD and turbidity using the new method (AD-EL method) were examined. The results demonstrated the AD-EL decreased COD and turbidity by about 72% and 85%, respectively. The perfect conditions to reach this removal levels were pH, RT and ET of 6, 30 minutes and 20 minutes, respectively.
Removal of organic matter from water using ultrasonic-assisted electrocoagulation method
Authors: Zanki Ayat K. , Mohammad Faris H. , Hashim Khalid S. , Muradov Magomed , Kot Patryk , Kareem Mohanad Mousa , Abdulhadi Bareq 
Published: August 2020

Abstract
Organic matter (OM) is commonly occur in freshwaters, and it poses a threat for health and environment. For instance, high OM concentrations increase the sludge volume and cost of the treatment process in turn. Remediation of water or wastewater from OM has thus become an important issue for the treatment industry. Electrocoagulation (EC) is one of the preferred techniques of treatment for remediation of water from OM and other polluting chemicals, as it utilises simple and easy to run machines and tools, it requires less working area in comparison with conventional methods, and it is more rapidly pollutant separation than other methods. EC technique could be described by passing an electric current through sacrificial electrodes to produce metal hydroxides that separate dissolved contaminants from aqueous phase. On the other hand, the EC method has a limited efficiency in the treatment of high OM concentrations. The present study is thus intended to develop a new technique that combines an EC reactor with an ultrasound (US) field to remediate water from OM. The EC reactor, in this study, was made from four aluminium plats (500 cm2 in gross area) and plastic container (1 L in volume). The operation of this combined method was optimised for the effects of key factors, such as the pH of solution, electrodes gapping, and current density. The obtained results proved that the US-EC technique removed 97.50 % of OM after 5.0 minutes of US irradiation, 20 minutes of electrolysing at current density 4.0 mA. cm−2, initial pH 7 and gap between electrodes 5.0 mm.
Natural filtration unit for removal of heavy metals from water
Authors: Abdulraheem Fatemah S. , Al-Khafaji Zainab S. , Hashim Khalid S. , Muradov Magomed , Kot Patryk , Shubbar Ali Abdulhussein 
Published: August 2020

Abstract
Occurrence of iron in the potable water is responsible for several issues related to environmental, economic, and public health. Water remediation from iron is very vital step for ensuring the safety of potable water. Hence, many treatment techniques, such as chemical precipitation and reverse osmosis, have been proposed in recent literature. However, these methods are either expensive or possess some negative environmental impacts. This paper therefore studies the possibility of utilizing farms’ wastes (straw and reed) to produce a filtration system for remediating water from iron ions. This natural filtration cell (NFC) was manufactured by mixing equal weights of straw and reed (1:1 ratio), while the artificial iron solution (10.0 mg.L−1) was synthesized by dissolving suitable amount of iron sulfates in deionized water. This artificial solution was treated in the NFC at different retention times (RTS) (ranging from 10 to 90 minutes) and initial pH of solution (IPS) (ranging from 4 to 9). The remaining iron in the solution, during the course of filtration process, was calculated utilizing a spectrophotometer and a standard iron cuvette test. The outcomes of this study revealed that 33.1% of iron was absorbed at RTS and IPS of 80 minutes and 7.0, respectively. Even though the research’s outcomes proved that the NFC possesses an acceptable capacity for iron removal from water, light brownish color was formed in the produced water, so another suitable treatment technique is needed to decolorize the produced.
Electrochemical removal of brilliant green dye from wastewater
Authors: Aqeel Khalifah , Mubarak Hayfaa A. , Amoako-Attah Joseph , Abdul-Rahaim Laith A. , Al Khaddar Rafid , Abdellatif Mawada , Al-Janabi Abuduljaleel , Hashim Khalid S. 
Published: August 2020

Abstract
Dyes are one of the most widely used materials in many industrial fields as coloring agents such as textile, wood, and food manufacturing. As these dyes end up in a water source, this high rate of dyes use represents one of the severe risks to the environment and health organizations. Most of the dyes are considered as highly toxic compounds and dangerous to the environment and human health as it consists of heavy metals, carcinogenic elements, oxygen – absorbing chemicals, and other toxic compounds that need to be well treated before discharge them back to environment. As a result, federal legislations have directed that all industrials that waste dyes-containing effluents to ensure a full dyes removal before discharging their effluents back to water bodies. Industries have applied many different treatment methods including physical, chemical, and biological methods in order to meet the required legislations. In recent years, many industries started to use electrocoagulation as the main treatment method. This study is focusing on using electrocoagulation (EC) method to remediate artificial colored effluents from coloring agents (brilliant green dye (BG dye) as a model). Electrocoagulation reactor, uses aluminum electrodes, was employed to remove this dye under different initial pH (40-10.0), direct currents (DC) (244-732 mA), and spaces between electrodes (SBE) (4-12 mm). According to the findings obtained, EC was highly efficient in treatment of colored effluents; 95.3% of BG dye was removed at treatment time, SBE, DC and pH of 30 minutes, 4 mm, 488 mA and 7.0, respectively.
Cost-effective hybrid filter for remediation of water from fluoride
Authors: Alhendal Mohammed , Nasir Mohsin Jasim , Hashim Khalid S. , Amoako-Attah Joseph , Al-Faluji Duaa , Muradov Magomed , Kot Patryk , Abdulhadi Bareq 
Published: August 2020

Abstract
Incidence of fluoride concentrations in drinking water above the allowable limit (1.5 mg/L) leads to varied health issues. However, fluoride concentration below 1.5 mg/L in drinking water is useful for teeth and bones health. A considerable concentration of fluoride is naturally released to the sources of freshwaters from the geological environment, specifically the groundwater, because of the weathering and seepage of water phenomena influences. Unfortunately, nowadays world population depend on groundwater as the main drinking water source, which means those people are exposed to fluoride contaminations. As a result, contamination of groundwater with fluoride has been lately considered as a universal grave issue. Although fluoride could be removed from drinking water using efficient methods, such as reverse osmosis and filtrations, there is a challenge to develop a cost-effective practical removal method. This study examines the efficiency of an economically-efficient a hybrid filtration cell (HFC), which utilizes limestone and activated carbons, for fluorides removal from water. Batch flow experiments were conducted using HFC to remediate artificial water from fluorides. Additionally, the influences of initial pH, initial concentration of fluoride (IFC), water temperature (WT) and adsorbent dosage (AD) were optimized, using Box–Behnken approach, to reach the highest removal of fluorides. The results demonstrated that fluoride could be completely removed from artificial water when the HFC is run at pH of 5.0, IFC of 30 mg/L, AD of 30 mg/L and WT of 313 K.
Effect of Construction Joint on Flexural Behavior of Reinforced Self compacting Concrete Two Way Slabs
Authors: Ismael Murtada A. , Hameed Yahyia M. 
Published: August 2020

AbstractThis paper investigates the influence of construction joints on the behavior of reinforced self-compacting concrete (SCC) slabs in flexure. The experimental scheme involves constructing and testing four slab specimens with dimensions of 450mm×450mm×60mm. One of the specimens is without construction joint as a reference, the second is of vertical construction joint at mid-span of the slab, the third is of horizontal construction joint at mid-depth and the fourth is of construction joint with key-shaped at mid-span. The outcomes of this investigation revealed that the influence of construction joint on the first crack load was more significant than that on the ultimate load. The slab with key-shaped construction joint gave better performance with regard to first crack load and ultimate bearing capacity as compared with the other cases with reduction percentages of 15% and 9.5% respectively as compared with the reference specimen, while the slab with horizontal construction joint in mid-depth represented the less efficiency case with reduction percentages of 40% and 22.8% respectively. Also, the load-deflection relationship becomes stiffer after the first crack load for the slabs with construction joint comparing with the reference specimen.
Low-velocity impact tests on self-compacting concrete prisms
Authors: Abid Sallal R , Al-Gasham Thaar S , Ali Sajjad H , Kadhum Ahmed L 
Published: August 2020

Abstract
Several structural members like columns and walls can be under the effect of accidental strikes from falling objects or collision of moving vehicles. Several researches are available in the literature on impact tests on different types of concrete, while those on Self-Compacting Concrete (SCC) reinforced with steel fiber are very limited. In this research, repeated impact tests were conducted on normal strength and high strength SCC reinforced with micro-steel fibers. Four fiber fractions of 0, 0.5, 0.75 and 1.0% by volume were investigated, while two design strength of 30 and 50 MPa were considered as normal and high strength SCCs. The test procedure was similar to the repeated impact test technique of ACI 544-2R but with a drop height of 100 mm and using prism specimens. The test results showed that micro-steel fiber can increase the impact resistance of SCC significantly. The inclusion of 1.0% fiber led to up to approximately 500% increase in the retained number of impacts at cracking stage, while the percentage increase at failure was much higher which reached approximately 2100%. On the other hand, the adopted high strength SCC could retained only up to approximately 30% higher number of impacts compared to normal strength SCC.
Spatial Analyses of Pavement Condition at Intersection Sites
Authors: AL-Kazaz Ahmed B , Ewadh Hussein A 
Published: August 2020

AbstractRepeated and periodic assessments of pavement conditions at intersection sites to improve the serviceability of intersection, is an essential component of the transportation system. Further, continuous maintenance of deterioration and defects that appear on the surface layers of pavement at intersection sites according to pavement condition indices (PCI), is a vital process in pavement management. This research aims at conducting spatial analysis for pavement conditions at intersection sites. The application of the developed measure is demonstrated for three signalized intersections in Hilla city, Iraq, by using distress definition. Point density Estimation (PDE) as spatial analyses and interpolation tool (IDW) in ArcGIS software is used to estimate the position intensity. PDE for Pavement condition applications enables the visualization and extraction of distress density in a selected zone or a network of road, which gives the makers of decision an advanced vision to the problem within a location. In this paper, PDE is used to generate potential distress hotspots map based on distress definition data. The result of this research shows the suitability of the heat map for the maintenance entitlement of a particular intersection. It gives a clear indication of the deterioration in the pavement layers depending on the severity of the colours shown in the heat map. For instance, a section of high score of PCI may include a very deteriorating units of low score of PCI due to the presence of many defects. Hence, it can be concluded that, it is doubtful that the PCI section represents the reality of all units. As a sample section (D) of the AL Thawra intersection where there were damaged units, PCI reached 55, 56, 59, while the PCI of section (D) was 74. The developed heat map demonstrates deterioration condition thoroughly for all units and provides advanced vision to pavement condition at the studied sites.
Gravimetric Analysis of Oil pollution of Tigris River
Authors: Humaish Hussein , Hafudh Wissam , Ismaael Baydaa 
Published: August 2020

Abstract
Environmental Pollution has become the first threat to humanity nowadays. Water pollution with petroleum products occupies the largest space because of its impact on the environment and waste of money. Oil is still one of the most important sources of energy currently used in the world. The aim of this research is to monitor and measure the intensity of the oil pollution caused by the oil spill leaks to the Tigris river and to treatment this leakage by oil booms. Six stations for remote sensing were distributed along the Tigris river to record oil concentrations. Each station consists of a sensor and a data reader that receives the digital data from the handsets and stores in the form of tables. Gravimetric analysis has been used to measure oil concentration. An organic solvent, hexane, was used to extract oil from the water. Oil booms have been used to collect spilled oil, preventing oil from spreading and changing flow direction for the purpose of collection. The process of scraping oil above the surface of water was done using oil scrapers.