bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficiency of different methods to predict settlement of shallow foundation in cohesionless soil
Authors: Mohammed Zainab R , Abdul-Husain Husain A 
Published: June 2021

Abstract
During the last decades, many methods have been developed to predict the settlement of shallow foundations on cohesionless soils based on the results of SPT. However, such prediction methods with the required degree of accuracy and consistency have not yet been developed. The current study is an attempt to evaluate the performance of some of these methods and obtain the most efficient one. This goal has been performed by evaluating and ranking eight common methods. These methods are Terzaghi and peck, Meyerhof 1, Bowles (1986), Parry, Schultze and Sherif, Meyerhof 2, Burland and Burbidge and Anagnostopoulos et al.. A total number of 189 cases published in the literature were adopted to carry out the ranking analysis of the selected methods. The concept of rank analysis depends in general on four approaches. These approaches are Nash-Sutcliffe efficiency, arithmetic average & standard deviation, accumulative probability analysis, and Log-Normal distribution of the ratio between the predicted and measured settlement. The results of the analysis revealed that the Anagnostopoulos et al. method have got the first rank with a rank index of 6 while Terzaghi and peck have achieved the last rank with rank index of 27. Therefore, Anagnostopoulos et al. method can be used to estimate the settlement of shallow foundations based on the results of SPT with high confidence.
Seismic effect on uplift bearing capacity of pile embedded in dry sand
Authors: Abdul Hussein Haider N. , Mohammed Shafiqu Qassun S. , Khaled Zeyad S. M. 
Published: June 2021

Abstract
The growing rate of occurrence of earthquakes in Iraq and the whole region has driven to conduct this experimental research aiming at evaluating the uplift capacity of piles under seismic influence. Shaking table was especially manufactured to simulate the seismic loading resulting from Halabjah earthquake with high accuracy. Pullout tests were carried out on piles embedded in dry sand to determine the ultimate uplift load capacity before and after applying the seismic loading for different length to diameter ratios (L/D) of pile model 20, 25 and 30 and for loose and dense dry sand. It has been found that the maximum pull-out load of the pile after applying only Halabjah seismic loading was reduced between (8.16%) and (10.46%) in loose dry sand. However, there is no clear effect on tension pile capacity in dense dry sand except in pile of L/D=30, that bearing capacity increased by about 15.94%. And when apply combined loading of Halabjah seismic loading and uplift loading equal to one-third of maximum tension capacity the reduction of maximum pull-out capacity was between (55.02% to 73.22%) in loose sand while in dense sand there is a reduction about 50% for pile with L/D=20 and 25% and a low reduction of 8.06% for pile with L/D=30.
Pavement condition index (PCI) for some highways collector selected in Najaf city implemented with PAVER software
Authors: Kareem Saba Abbas , Shubber Khawla H. H. 
Published: June 2021

Abstract
Pavements are the main assets of highway infrastructure. Pavement Condition Index (PCI) is a numerical index used to describe the general condition of a pavement. This paper is another trial in monitoring and find pavement condition index (PCI) by applying PAVER software version 5.2. This work aims to evaluate (PCI) of a flexible pavement of some miner collector highways in the north sector in Najaf city divaricate from both sides of Najaf- Karbala suburban main collector highway in its part away from Al- Askariin intersection towards Karbala. These highway sections are Al-Rahma, Al Hizam Al Akhdar, and Al Muearid, Al Shamalii garage highways which cover a total length approximately 11.54 km in both direction of traffic movement (diverging from Najaf- Karbala highway and return to it). Field survey data such as highway section geometric design and distresses type, dimension, and severity, were collected depending on sample size and number of samples extracted, and then entered into the PAVER program to calculate PCI. The result of PAVER shows Results approved that Al-Rahma and Al Shamalii garage highways sections are in satisfactory level, while Al Muearid highway section in (fair) and Al Hizam Al Akhdar in worst case (poor). In addition to that, reasons of these defects had been figuring out according to results obtained.
Optimization of replacement fines in roads base materials by cement/ lime
Authors: Jasim Heydar A , Mahdi Zaid A , Al-Obaedi Jalal T S 
Published: June 2021

AbstractThe road networks in Iraq suffer from the increase in the proportion of highly carriage trucks and vehicle growth rates, which requires improving the layer’s characteristics and using protective methods accomplished with suitable costs to achieve high quality and fewer cost treatments. This paper investigates the effect of modifying sand -gravel soil as a base layer by using cement or/ lime as a replacement to the original filler. The mechanical properties of the mix were evaluated based on compaction, CBR, and compression strength tests. The results for the CBR test suggested that there was an increase in bearing ratio when replacing a percent of filler by cement or lime as compared with the origin material, and the percent of replacement by cement or lime was 30% of origin filler. The results for the compression strength show that there is an increase with increasing percent of filler replacement by Cement, on the contrary, the Lime increase reveals a decrease in strength. The replacement with cement was better than that of lime. Lime should be used in less than 30% from point of view cost and strength. The findings of this paper suggested that adopting the method will result in decreasing the thickness of the pavement layer. The best results obtained when adopting 100% replacement by cement (10% by total weight) which gave the best reduction in the required thickness by about 62%. Regarding the lime use, the results revealed optimal percent of lime to be used is about 3% of total weight.
Assessment the performance of asphalt mixtures modified with waste tire rubber at high temperatures
Authors: Al-Rubaie Ali H. , Joni Hasan H. 
Published: June 2021

Abstract
Quality of roads pavement can consider as one of the essential criteria for the good transportation system. So, to reduce the problems of fatigue crack and rutting of roads, several actions have been taken including the improving of pavement quality and the structure design methods. The increasing in the attention of traffic engineers in the last few years to modify and improve the asphalt performance through providing a different type of additives and replace the raw materials of asphalt mixture with recycled materials, in order to improve the environmental as well as reduce the cost of modified pavement mixture. There were several types of research investigated the validity of using the waste material products in the mixtures of asphalt pavements, since these replacement materials could improve the performance of roads pavement, the researches that adopted the influence of usage recycle waste materials to improve performance of the asphalt of the road still limited compared with other construction fields. This paper briefly discussed the modified asphalt mixtures performance and the most used recycled material which is crumbs rubber used as modifier in the HMA. By using various proportions of crumbs rubber (2.5, 5, 7.5, 10, 15 and 20% by weight of asphalt), and investigate the effect of adding rubber crumbs waste on the most important dynamic and mechanical properties of asphalt mixtures, which is the rutting resistance. It aims also to understand the benefits and disadvantages of using recycled tire rubber and develop the idea on good inclusion of waste material in the road pavements.
Mechanical strength and hydraulic properties of modified porous concrete mixtures
Authors: Almansori Hussein J. , Al-Sibahy Adnan , Al-Humeidawi Basim 
Published: June 2021

Abstract
This study presents a comprehensive experimental investigation on the behavior of porous concrete mixtures intended to be used as surface road layer containing mineral admixture. Silica fume and/or fly ash were used to formulate modified concrete mixes at ratios ranged from 10% to 20%. A systematic change in 50% of the 9.5 mm aggregate particles size was adopted throughout single size coarse aggregate of 5mm. This in turn produces two groups of concrete mixes and eight individual mixtures. The compressive and tensile strengths, voids content and permeability characteristics were measured and the obtained results were compared with relevant guide of porous concrete. The results showed that a moderate strength of 24 MPa can be obtained at early ages. For the same concrete mixture, the values of voids content and permeability were 21.7% and 19.3 mm/s, respectively. Such kind of concrete can be used in construction of roads and it helps in water draining purposes.
The effect of elimination the left-turn movements on the intersections Capacity-A simulation study
Authors: Al-amedy Tabarak A , Al-Obaedi Jalal 
Published: June 2021

Abstract
Left-turn movement is an important element to determine the capacity of intersections due to high conflicts points. Therefore, finding the alternatives for such left turn movements may increase the intersection throughput and make it safer. This study discusses the effect of eliminating the left turn movements on the intersection capacity by adding U-turn sections after each approach to apply the left turning away of the intersection. This means that the left turn traffic will pass the intersection using through movements, use the added U- turns and use the intersection again to reach the destination direction using right turns. To apply such scenario, traffic simulation has been applied as a tool using Paramics traffic simulator which is one of the most confident tools over the world. Simulation models have been developed using Paramics considering both signalized and un-signalized intersections with different effective green times. The results suggested that applying such alternatives will significantly increase the intersection capacity. However, further research is needed to examine the geometric layout that would be useful for such alternatives and to confirm the validity of the findings by validation the developed simulation models.
Operational assessment of biological wastewater treatment using advanced return-mass reactors based on principal component cluster analysis
Authors: Najy Rana Hasan , Al-Obaid Basim Hussein Khudair , Salman Mohammed Sadeq 
Published: June 2021

Abstract
In this study, field results data were conducted, implemented in 64 biofilm reactors to analyses extract organic matter nutrients from wastewater through a laboratory level nutrient removal process, biofilm layer moving process using anaerobic aerobic units. The kinetic layer biofilm reactors were continuously operating in Turbo 4BIO for BOD COD with nitrogen phosphorous. The Barakia plant is designed to serve 200,000 resident works on biological treatment through merge two process (activated sludge process, moving bed bio reactio MBBR) with an average wastewater flow of 50,000 m3/day the data were collected annually from 2017-2020. The water samples were analysis in the central laboratory of the wastewater treatment plant in Barakia region by the Directorate Sanitation in Najaf is influential, wastewater at the treatment plant for Al-Bio-shaft saw major water quality parameters. The data was analysis of using a principal component approach a cluster study of the return-mass reactors. The results showed that the biological oxygen dem (BOD5, 126 mg / L), chemical oxygen dem (COD, 222 mg/L), total solids, total suspended solids (TSS, 223 mg/L) a pH of 7.6 over a period of 4years, also the optimum removal rate was 89 %of the BOD, under optimum conditions, 78 % of the chemical oxygen occurred in the air reactor by nitrification with an average ammonium removal yield of 67 %. The cluster analysis results showed that the years (2018, 2017, 2020) are a good level of treatment compared to 2020. The final effluent quality (an average value of three years) complies with the stringent regulations proposed by the Iraqi National Stards established by Regulation 25 of 1967 BOD / COD ratio were calculated Influence is 0.63 in total wastewater.
Evaluate the performance of horizontal flow wetlands as an option for tertiary treatment of secondary sedimentation basins
Authors: Qasid Dounia Jamiel , Ali Sura kareem , Ahmed Mahmood Dhiab 
Published: June 2021

AbstractConstructed wetlands (CWs) are simple low-cost wastewater treatment units that use natural process to improve the effluent water quality and make it possible for its reuse.in this study used the horizontal flow system for the tertiary treatment of wastewater effluent from secondary basins at Al-Rustamiya wastewater treatment plant / old project / Baghdad / Iraq. the Phragmites Australis plant was used for wastewater treatment and the horizontal subsurface flow system was applied. the experimental study was carried out in February 2020 to October 2020. the parameters were monitored for a period of five weeks, Concentration-based average removal efficiencies for HSSF-CW were COD,53% [NO]_3,41.3% [PO]_4,52% and TSS, 54.2%. Thus, constructed wetland can be considered as a sustainable alternative to the tertiary conventional treatment of wastewater, thus making it possible for reuse..
A state of the art review of fiberless and steel fiber reinforced high strength concrete columns behavior under various loadings
Authors: Al-Qabbani Hussein K , Aljazaeri Zena R , Al-Hadithy Laith K 
Published: June 2021

Abstract
Efficient supplementary materials flourish the structural performance and sustainability of reinforced concrete structures. Steel fiber is one of these materials that have significant influence on enhancing tensile and flexural strengths and ductility of high strength reinforced concrete columns. This paper presents a review study on the structural performance of steel fiber reinforced concrete columns. The studied case was related to the columns that subjected to concentric or eccentric compression loads or combined compression loads and cyclic lateral loads. The current survey is divided into two branches; the first is related to fibreless HSC columns, while the other is specialized by SFRHSC ones. In addition to the prime actuator (steel fiber content), the investigated parameters were included concrete strength, transverse reinforcement properties, and axial load ratio. The results of this investigation showed that the positive influence of adding steel fiber on improving the flexural strength, fatigue life and resistance, delaying spalling failure of the exterior concrete shell and outward buckling of the longitudinal steel reinforcing bars. The optimum volume fraction of steel fiber used is 0.5% to 2% (by weight) and when 2% of steel fibers are introduced into the concrete mix, the columns’ cover didn’t spall away.
The behavior of reinforced concrete columns exposure to eccentric loads at high temperature
Authors: Al-Naqeeb Faaiza , Al-Thairy Haitham 
Published: June 2021

Abstract
This paper aims to investigate the influence of high temperature on the reinforced concrete columns’ behavior and load-carrying capacity when subjected to eccentric loads. Experimental tests were conducted on four RC column specimens reinforced by steel bars and subjected to four levels of temperatures: 20 ºC, 400 ºC, 500 ºC, and 650 ºC. One of these specimens was exposed to ambient temperature and considered as the control specimen. After exposure to elevated temperature, all columns were axially loaded by compression force using an eccentricity ratio (e/h) equal to 0.5. The experimental test findings demonstrated a remarkable decrease in the RC column’s ultimate carrying capacity when subjected to elevated temperature. The columns’ ultimate load capacity decreases by about 14.286 %, 28.571 %, and 42.857 % at elevated temperature magnitude of 400 ºC, 500 ºC, and 650 ºC respectively, compared with the control column at ambient temperature. Also, an increase in fire temperature resulted in a reduction in the load capacity with an increase in lateral and axial deflection of tested columns.
Early Age Temperature Distributions in Concrete Bridge in the Middle of Iraq (Experimental Study)
Authors: Laibi Noor M. , Shallal Muhaned A. 
Published: June 2021

Abstract
The temperature difference between the inside and outside of the concrete bridge causes the appearance of early cracks in the concrete bridge. The thermal cracks are appeared on surfaces or inside the bridge body. The sources of the thermal loads come from solar radiation, air temperature, wind speed, and the heat of hydration of cement after pouring concrete (at the early edge of concrete). Concrete T-section used to study the temperature distribution at the early edge, fourteen thermocouples used to measure the temperature during the day; these thermocouples were placed in the different location inside the concrete bridge as well as on its surface. The temperature-time curves were obtained for each thermocouple, from these curves it was found that the effect of cement hydration on the internal temperature was during the first 48 hours, while the effect of solar radiation was evident during daylight hours on the top surface of the model. The effect of solar radiation continues while the effect of cement hydration vanished after 48 hours.
Effect of using column capital on the punching shear strength of flat slab-edge column connection under eccentric loading
Authors: Jasim Attaa H. , Ammash Haider K. 
Published: June 2021

AbstractThe influence of column capital on punching resistance at the edge column is virtually not fully studied. This is a significant omission, as column capital under eccentric loading can arise in flat slab buildings under lateral loading from wind and earthquakes. This paper deals with the effect of using reinforced concrete column capital on the punching shear strength of the flat slab-edge column connection under eccentric loading. The study involves testing experimentally six reinforced concrete flat slab-edge column models with dimensions (1000×1600×100 mm) with two different dimensions of column capital (300×400 mm, and 500×800 mm) in addition to reference model without columns capital (column dimension 200×200mm). Two specimens as a control without columns capital where the first specimen under axial load according to column section but another under eccentric loading with eccentricity (e=half width of column). The effect of size of the column capital and were studied experimentally. We observed an increase in punching resistance by (17.02% and 27.66%) respectively over that of the reference specimen under axial load, and about (18.18% and 25%) respectively over that of the reference specimen under eccentric loading.
Assessment of the flexural capacity of composite reinforced concrete beams using experimental tests and finite element analysis
Authors: Witwit Dolfocar Ali Usamah , Jasim Prof. Dr. Nabeel Abdulrazzaq 
Published: June 2021

Abstract
One of the main governing matters points in studying the composite reinforced concrete beams (CRC) is the force transmission mechanism at the interface between the concrete and the steel section. In this research, a new connection method for CRC beams consisting of reinforced concrete and steel T-section is studied. In this method, the stirrups are utilized to perform as shear connectors. The experimental part of the study includes studying the flexural behavior of the CRC beam with different degrees of interaction. The theoretical part of the study includes constructing a three-dimensional finite element model using ABAQUS software and validating the model using the experimental results. The model was verified by comparing the critical local and global responses of the CRC beams such as the beam deformation, load at which the steel T-section reached yield point, and concrete cracking and crushing. The model showed a good correlation for the estimation of ultimate load with an accuracy of 105% was achieved.
Investigation of temperature gradients in composite girders in the southern region of the black sea
Authors: Mussa Faten I. , Abid Sallal R. 
Published: June 2021

Abstract
Based on an experimental composite concrete slab-steel beam girder and using a verified finite element thermal model, a case study analysis was performed to evaluate the temperature gradients in composite girders in the Black Sea’s Turkish city Samsun. The case study was conducted based on extreme data records of approximately 50 years. The extreme daily solar radiation and air temperature difference were utilized in finite element thermal analysis for six months that represent the different seasons of the year. The investigated months were the hot months (April, June, and July) and cold months (October, November, and December). The study focused on the vertical temperature gradients (along the vertical centerline of the girder) and the lateral temperature gradients (along the horizontal centerline of the topping concrete slab). The finite element results showed that the maximum vertical temperature gradient occurred in June and was 13.55 °C, while the maximum lateral temperature gradient occurred in December and was 10.11 °C. The results also showed that different behaviors of the positive vertical gradient were recorded for the cold months than those for the hot months. Similarly, the distributions of the positive lateral gradients were different for the two groups of months. These differences were attributed to the different sun movements and solar radiation striking angles in summer and winter.
Application of dynamic calibration and control waveform optimization techniques in the fast sweeping reflectometer upgrade on the HL-2A tokamak
Authors: Yang Z.C. , Jiang M. , Shi Z.B. , Zhong W.L. , Shi P.W. , Liu Y. , Wen J. , Fang K.R. 
Published: June 2021

Abstract
High temporal-spatial density profiles, measured by the frequency modulated continuous wave (FMCW) reflectometer, are crucial for the study of particle transport and confinement, especially for the transient events. However, the conventional calibration methods and control waveform of the voltage controlled oscillator (VCO) source constraint the increase of the sweeping frequency (time resolution) and the accuracy of the probed location of the FMCW. In this work, two methods of dynamic calibration of the VCO are proposed to reduce the measurement error due to the high sweep rate, and the results are found to be consistent with each other. In addition, the control waveform of VCOs are re-designed considering the VCO calibration results and dispersions of the waveguide and cables. Therefore, the sweep/dead time has been shortened to be 10 μs/50 ns from 25 μs/5 μs and the accuracy of the detection location has been improved significantly. The density profiles and density fluctuations during the tearing modes are presented which demonstrate the capability of the upgraded reflectometer.