bluuebunny/crossref_metadata_2025 huggingface dataset:
Studying the influence of fiber reinforcement on the characteristics of roller compacted concrete used in airports with partial replacement of cement by cement kiln dust
Authors: Al-Tameemi Ali A , Alkelabi Ehsan A M
Published: August 2020

Roller-compacted concrete is defined as that concrete of no-slump consistency in its’ unhardened state that is transported, placed, and compacted by roller compaction. The purpose of this research is to study the effect of using steel fiber reinforcement on the properties of roller compacted concrete in which, 5%, and 10% of the cementitious materials were replaced by cement kiln dust. Different contents of steel fibers were used to reinforce concrete which were compacted using a manually controlled roller device. The results showed that the compressive strength of the roller compacted concrete with 5% replacement of cementitious materials increased by 19, 25, 32, and 42%, when the concrete was reinforced using steel fibers amounts of 30, 50, 70, and 90 Kg per m3of concrete respectively. The corresponding increases in the flexural strength were (15, 34, 37, and 40%). Similar increases were recorded for specimens with 10% replacement. The research had confirmed the feasibility of using steel fiber reinforcement to enhance the properties of this kind of concrete to be used in airport pavements. Substitution of 5 to 10 % of the cementitious materials by cement kiln dust will save energy and contribute in decreasing the impact of pollutants on the environment.
Experimental investigations of the structural behaviour of simply support ferrocement-timber composite beams
Authors: Jaafer Abdulkhaliq A. , Hussein Karrar K. Abdul
Published: August 2020

An experimental study of simply supported ferrocement timber composite members is presented in this paper. An adhesively bonded connection is examined. Sikadur 31 thixotropic epoxy resin adhesive is used as a shear connector layer. The main purpose of the research is generating data and providing information about the structural behaviour of proposed ferrocement timber composite (FTC) beams. Several parameters studied including thickness, and width of timber beams, the number of wire mash layers of ferrocement slab and the presence and absence of a bonding layer of the shear connector and the effect of sag and hog bending moment. Ferrocement-timber composite (FTC) beams are a relatively new civil engineering solution and their behaviour should be investigated to develop relevant methods for calculating their resistance. The slip and the pinnacle load limit for connector were resolved tentatively in two push-out tests. The authors examined the stiffness and the strength of the connection used to join a ferrocement slab with a timber beam. These parameters are fundamental for planning composite beam, on the grounds that the conduct of a composite beam framework is relied upon the solidness and the quality of its associations. The composite beams specimens were subjected to a three-point loading test. Measurements also show that the connection could be considered perfect as the slip remains very little during the test (except at failure). Tests disclosed excellent loading capacity of the suggested beams relative to their weight. The use of epoxy resin can be providing appropriate bonding between the two layers. The energy absorption increases with increasing dimensions of timber. The maximum increase in load with increasing the depth of timber (72.5%) when the thickness of timber Change from (85 to 190) mm.
Review on Soil-Structure Interaction Problems
Authors: Daud Khalida A.
Published: August 2020

This work comprises a survey on former work on the response of structures resting on soil and method used in the analysis of problems. Several techniques were used earlier by other researchers, some of these based on closed form or series solutions and the other problems were solved using numerical technique (finite differences or finite elements). Beam, plate or 3D solid elements were used in the finite elements to model structural members whereas spring elements were used to model the soil. Also, the finite difference was used to formulate the problems of plates or beams placed on Winkler springs. Moreover, the series solution of the differential equations using Fourier series programmed in various computer languages was used in the previous studies to analysed such problems. The numerical analysis showed to be very effective in solving problems involving structures resting on the ground.
Cost and time reduction of concrete slabs construction by selecting the most economical structural design
Authors: Al Kulabi Ahmed K , Al Zahid Ali A
Published: August 2020

In construction industry, projects are usually completed in a budget more than what is estimated for, finished in a time more than the contracted time, not executed properly according to the specifications, and not constructed with the client satisfaction. The thing that causes lowering the profits of contractors, clients losing, time to market prolonging, and other consequences. Projects execution on or under the budgeted money requires valid practices, precise decisions, good strategies, and needs developing new techniques, such as cost reduction technique. Thus, this paper mainly aims to relieving part of the big concerns of those who specialized in construction media respecting construction cost overruns by determining the most economical structural design, which can be realized by studying, quantifying, analysing cost, and comparing a number of structural elements with different dimensions, different design combinations, and different materials proportions. Then, the optimum structural element, the element that meets the design requirements, comprises the least materials quantities, and costs least, was selected in case to achieve an economical construction.
Forecasting of monthly stochastic signal of urban water demand: Baghdad as a case study
Authors: Zubaidi Salah L. , Al-Bugharbee Hussein , Muhsin Yousif Raad , Hashim Khalid , Alkhaddar Rafid
Published: August 2020

Forecasting of municipal water demand is essential for the decision-making process in the water industry in particular for countries that suffered from water scarcity. An accurate prediction of water demand improves the water distribution systems’ performance. This study analyses the water consumption data of Baghdad city using a signal pre-treatment processing approach aiming at a stochastic signal extraction of such data. An autoregressive (AR) model is then applied to predict monthly water consumption. Our prediction model has been trained and tested using a water consumption data captured from Al-Wehda treatment plant between 2006 and 2015. The results reveal that applying signal pre-treatment method was an effective approach for detecting stochastics of our water consumption data, and the hybrid model was reliable for the prediction of water demand.
Structural Behaviour of Hollow Core Reinforced Self Compacting Concrete One Way Slabs
Authors: Mahdi Ahmed A. , Ismael Murtada A.
Published: August 2020

Hollow-core slab (HCS) is a voided slab that has longitudinal voids made by recycled plastic pipes that were placed in the middle of the slab thickness where the flexural stress is minimum. These longitudinal voids can reduce the volume of slabs to more than 30% which leads to save raw materials and satisfying sustainability, economic considerations, and a clean environment. The experimental program comprised casting six slabs with dimensions of 1700mm × 435mm ×125mm, one of them was solid slab as a reference slab and the other five slabs were HCSs. These slabs were divided into two groups, the first group consisted of three HCSs with different numbers of longitudinal voids, and the second group consisted of three HCSs with different diameters of longitudinal voids. The results of the test showed that increasing numbers of longitudinal voids can save the ultimate load with percentages 93.47%, 87.63%, and 82.92%, with increasing the ultimate deflection by 8.72%, 21.57%, and 28.31%. Also, increasing the diameter of longitudinal voids can save the ultimate load with percentages 93.37%, 90.01%, and 87.63% and increase the ultimate deflection by 6.58%, 13.26%, and 21.57% respectively when compared with the reference slab.
Development a capacity model for Al-Turkmani roundabout
Authors: Shadhan Laith Q , Alkaissi Zainab A
Published: August 2020

In this research, the main aim of this paper is to develop a statistical model for the total capacity of the roundabout as a function of influence traffic features and driver factors. The variables remain predicted to simulate the characteristics of the traffic that have most influence the capacity of the roundabout; classified as traffic conditions such as critical headway, follow-up headway, and driver behavior are involved in the building of the model by using SPSS statistical program. 30 samples have been taken, each sample representing an average of 15 readings for 15 minutes, equivalent to 450 readings for each of Critical Time Headway, follow up headway for each lane (Right, middle, Left) and Driver Factor for model one, for model 2 only Follow up time headway for the Middle lane and Driver Factor have been used. All tests for checking outliers, normality and correlation between independent variables with each other have been used for both models. Model 2 is the most significant with R2 = 91%. Validation of Observed and Theoretical Capacity is strongly liner with a Correlation coefficient = 0.938, the statistical model proves that the Follow-up headway time and driver factor have been influenced effect on the total capacity of the roundabout.
Investigation of Torsion behavior of high strength short fiber reinforced concrete deep beams with openings
Authors: Ahmmed M A , Chkheiwer A H , Kadim J A
Published: August 2020

This study aims is to investigating the structural capacity of fibbers reinforced deep beams with opening under pure torsion. The deep beams were made of high strength concrete. The openings were made in the web with different shapes (circular and square), sizes and located at the mid span. Seventeen deep beam specimens were casted and they experimentally investigated throughout this study. The constants in this study are beam dimensions and compressive strength for concrete. The effects of the shape, size and locations of opening on the torsional behaviour of deep beams under torsional loading are studied in the paper. The results showed the square opening is weakest due to the concentration effect which increases the stresses and the opening size participate main role in strength of deep without steel fiber. Also, the steel fibre in which the presence of steel fiber causes increasing in the torsion strength about (30-32) of tested specimens.
Mechanical properties of green concrete
Authors: Al-Azzawi Adel A , Al-Azzawi Ayad A.
Published: August 2020

The engineering properties inspection of green concrete resulted from using Metakaolin to replace cement and crushed tiles as waste coarse aggregates is the main aim in this work study. Different concrete mixtures were prepared in order to obtain 30 MPa target strength for concrete in compression. The crushed tile as waste aggregates is used to substitute crushed gravel as natural aggregate with ratios of 0 to 100% in the concrete mixtures and the mixture properties were inspected. It is revealed that employing Metakaolin in the replacement of cement and crushed tile to substitute a ratio of crushed gravel affects all concrete properties such as; elastic modulus, tensile strength, and compressive strength. The difference relies on the percentages of Metakaolin and aggregate substituted. The optimum percentages for both Metakaolin and waste aggregate were found to be 20% and 25% respectively which can be used to produce green concrete with acceptable properties and solve a very important environmental problem. The ACI 318 code equations for estimating the spilt cylinder and modulus of elasticity are used and it is revealed that these equations give overestimated values for green concrete having waste aggregate with percentage exceeding 25%.
Investigating skimming flow conditions over stepped spillways using particle image velocimetry
Authors: Zuhaira A A , Horrillo-Caraballo J M , Karunarathna H , Reeve D E
Published: August 2020

Turbulent flow over stepped spillways can be considered the most significant flow that can cause severe problems at the downstream side, near the toe of the structure, such as sediment erosion which normally occurs due to the high amount of water energy. The presence of turbulent flow over the steps can cause cavitation damages due to pressure differences over the steps. The turbulent flow, which is induced at certain times of the year, especially during the flooding seasons, is examined experimentally and numerically in this study. Flow measurements were conducted using Particle Image Velocimetry (PIV) system in a hydraulic flume where the dam break condition is applied in order to achieve the skimming turbulent flow. Two cases of stepped spillways were tested, normal stepped spillways and gabion stepped spillways. For each case, measurements of the instantaneous turbulent velocity field were taken at different locations of the physical models of a slope of (1V:2H). A comparison has been conducted between the gabion and normal steps to assess the required time to attach skimming flow. The results indicated that the presence of the porous media could increase the required time to attach skimming flow.
Calculation Crop Coefficient of Okra with respect to Multi parameters by using dimensional analysis
Authors: Hommadi A H , Dahir F M , Alwan H H
Published: August 2020

The dimension analysis is solve to more difficult problem, simplify to difficult equation, reduce the many parameters in equations and search on the parameters more effect of equations. Increase the evaporation from soils and surfaces water with increase transpiration from plants because of raising in temperatures and reducing in humidity are problems of the times which effect on reducing of water. To solve the problems must research on formulas which give actual effects to control on the water reduction by evapotranspiration. In this study will search on methods to solve the crop coefficient (Kc) and evapotranspiration (ET) with multi variables. In this research will be driven equations by statistic of excel program of reference evapotranspiration (ETo) and crop evapotranspiration (ETc) with respect to. From equations and drawings were obtained on maximum value of correlation coefficient(R2). In addition to use the dimension analysis to multi variables (time, number hours of days, relative humidity, change of moisture content, hydraulic conductivity, root depth and temperature) with maximum value of (R2). Researching on equations and methods help to obtain results instead of going back to tables and curves as well reducing field tests that are tired. From equations of EToand ETcare obtained on R2=0.999 and R2=0.997, respectively from data. From statistic and dimension analysis equations are obtained on result very close with field data with little difference 10% and 4.28%, respectively.
Asphalt mix design Using Matlab Computer Program
Authors: Al-Hdabi Abbas , Al-Nasire Jaafar M , Mohsin Nadia A
Published: August 2020

An accurate asphalt mix design is a big issue to produce high quality pavement layer. Introduce a computer program that can be used to design different types of asphalt concrete layers i.e. base, binder and surface course will be very helpful. Therefore, the authors are introducing Asphalt Mix Design by MATLAB Program (AMDMAP) software to be used as a replacement to the manual calculations. The input data such as the characteristics of the used materials and lab work results must be available to run this program. The main output will be indicating the optimum asphalt content. Also, the relationships between Marshall Stability, Marshall flow, mixture density, Air Voids, Voids in Mineral Aggregate and Voids Filled with Asphalt vs different contents of asphalt will be produced. Mixture properties at optimum asphalt content will be indicated. Furthermore, the results will be compared with the standard specification of roads in Iraq.
Modeling and dynamic analysis of bridges designed with AASHTO and Florida I-beam girders
Authors: Al Fadul M A , Darwash H H
Published: August 2020

A comparative analysis of the dynamic behavior of two prestressed concrete girder bridges was implemented. The first bridge was designed with AASHTO (American Association of State Highway and Transportation Officials) type III girders while the second bridge was designed with the new (FIB) Florida I-Beam girders. Both bridges have the same length, width and girder depth. However, six AASHTO Type III girders were used in the first bridge versus only four FIB girders for the second bridge. The bridges response to dynamic loads was obtained with the aid of a sophisticated finite element model. Modal and time history analyses were performed for the bridges to identify the dynamic properties, behavior, and responses of the two bridges. The dynamic properties and the deflections of the bridges were obtained and compared for different girders and spans. Outputs from the finite element model indicated that although FIB bridge has less number of girders, the deflections of FIB bridge were less than their corresponding values from AASHTO bridge.
The urban relationships between Imam Ali’s shrine and the old city of Najaf in the south of Iraq
Authors: Falah Shubber
Published: August 2020

Najaf city in southern Iraq has developed around the burial site of Imam Ali, the cousin and son-in-law of the Prophet Mohamed. The grave of Imam Ali was the first element of Najaf, and the only reason behind its emergence1. At the same time, the city has positively impacted the number of Shi’a pilgrims by providing them with services. This mutual relationship between the shrine and the city has autonomously evolved throughout history and has always been a mutually co-dependent relationship. However, since 1954, when the Iraqi central government created wide roads around the shrine and through the city to accommodate motor vehicles, the relationship slightly altered2. This paper evaluates the current relationship by exploring the historical evolution of the city. For this purpose, three questions will be examined: 1) To what extent have Shi’a Muslim beliefs impacted the design of the city? 2) How did the city and Ali’s shrine evolve together? 3) How have the shrine, the main market of the city, the Wadi Al Salam cemetery, and the residential sector, functioned and influenced the evolution of the city as a whole?
Traffic Characteristics of Two-WayTwo-Lane (TWTL) Highway in Iraq: Al-Mishkhab Road As A Case Study
Authors: Al-Zerjawi Ahlam K. , Al-Jameel Hamid A. , Zagroot Sajad A.
Published: August 2020

Two-Way Two-Lane (TWTL) highways have been developed rapidly throughout the world, and they represent a large percentage of the road network spread about the world. In Iraq, this type of road still has also been adopted widely. Therefore, this study tries to investigate the two-way, two-lane highway characteristics because very few studies have been devoted to studying this topic in Iraq. Three sections of this type of highway have been selected along Al-Mishkhab city as a case study. The data collected include flow, headway, number passing and speed. A speed gun was used to measured speed in the selected sections. The passing frequency was high and amounted to about 240passings/hr. Further, the speed distribution was normal. The results of this study indicate that the number of passing vehicles is up to 240 passes/hr/km at 1200 veh/hr. In addition, as flow increases more than 1200 veh/hr, the number of passing vehicles decreases because of absence the adequate gap for such passing.
Removal of iron from wastewater using a hybrid filter
Authors: Abdulla Gameel , Kareem Mohanad Mousa , Hashim Khalid S. , Muradov Magomed , Kot Patryk , Mubarak Hayfaa A. , Abdellatif Mawada , Abdulhadi Bareq
Published: August 2020

Limestone is originally generated from sedimentary rocks that are mainly made from CaCO3, the latter in turn is made from calcites and aragonites. This chemical composition of limestone makes it a suitable material for water/wasters treatment as these elements are identified for their capability to adsorb several pollutants. Although, limestone is environmentally sustainable material and is broadly applied in water filtration, it is has a moderate affinity for heavy metals. Thus, due to this serious drawback, limestone becomes less attracting for researchers. Therefore, this study is aiming at producing an environmentally sustainable filtration system by mixing limestone and activated carbon, and applies it to remove heavy metal (iron) from synthetic wastewaters. The ability of the new filtration media, which was made of 50% activated carbon and 50% limestone (1:1 ratio), to remove iron from 10 mg/L synthetic iron solution. The latter was created using ferrous sulphate heptahydrate and deionised water. The removal of iron was optimised for the influence of the absorbent dosage (AD) (500-1000 g), detention time (DT) (10-120 minutes) and pH of solution (4-10). The outcomes of the experiments evidenced the capacity of the new filter to efficiently remediate wastewater from iron. Where, 1000 g of this filter needed only 95 minutes, at pH of 6.0, to completely remove iron ions from the synthetic solution.
Electrochemical removal of nitrate from wastewater
Authors: AL-Housni Mohammed , Hussein Ameer Hashim , Yeboah David , Al Khaddar Rafid , Abdulhadi Bareq , Shubbar Ali Abdulhussein , Hashim Khalid S.
Published: August 2020

There are many natural elements that cause pollution of groundwater and surface water. Nitrate is one of those pollutants that could cause serious problems to the aquatic life and human health. Consequently, environmental organisations and most of the governments around the world limited nitrates in potable water to 50 and 10 mg/L for adults and babies, respectively. The current research explores the removability of nitrate from industrial effluents using an electrochemical cell (ESE). The latter is a laboratory-scale batch flow cell having steel electrodes. The experiments were conducted using nitrates solution having100 mg/L. This investigation also studied the impact distance between the electrodes (SBE), treatment period (TP), current density value (CDV) and the initial pH on nitrates removal. Box-Behnken design technique (BBD) has been utilized to optimize the impacts of TP, CDV, SBE and pH on the removal of nitrates by ESE and also to generate a regression model to simulate the removability of nitrates by the ESE. The results of this investigation indicated that the optimum removal of nitrates was 93.4% that achieved at TP of 60 minutes, SBE of 0.5 cm, CDV of 3 mA/cm2and initial pH of 6. Furthermore, the developed model’s findings were in a respectable compatibility with the experimental findings (R2=0.904). In conclusion, the current investigation indicated that the ESE has good capacity to remove nitrate.
The shear strengthening of reinforced concrete beams by embedded through section technique -analytical study-
Authors: Tuma Noor K , Al-Ahmed Ali H , Al-Farttoosi Mahdi H
Published: August 2020

Five proposed simply supported RC beams were numerically tested by finite element method using ABAQUS software to investigate their behavior and shear strength when strengthened by embedded through section technique (ETS). All beams have the same dimensions of (160 × 250 ×1140) mm and were insufficient reinforced in shear. One beam is taken as a control beam. While, the other four beams were strengthened ETS CFRP bars and divided into two groups. The first group is with 13mm ETS CFRP bars (one bar per section). While, the second group is with 10mm ETS CFRP bars (two bars per section). For all groups, two styles of ETS inclination are considered, vertical and inclined by 45°. From the numerical tests, it was found that using ETS with 2φ10 inclined CFRP bars is the most effective technique for enhancing both the first cracking load about 100% and ultimate load capacity about 86%.
Flexural Action of Continuous Reinforced Reactive Powder Concrete Beams
Authors: Kareem Rawaa R. , Deyab Hasanen M.
Published: August 2020

In this current study can be split into two aims next its two aims. The first aim was to study the effectiveness of steel fibre ratio from (0 to 2.5%) on the flexural action of RPC continuous beams. The other aim was to investigate the effectiveness of longitudinal reinforcement bar on the flexural behavior of RPC continuous beams by using (CFRP and GFRP). Therefore, seven continuous beams consist of two span were searched under one-concentrated load for each span. All specimens had the same dimensions 150 mm width, 250 mm depth and 2700 mm length. The experimental outcomes display that the continuous samples made with RPC had an excellent compressive strength and that the maximum load improved when steel fibre ratio increased. The maximum load of the continuous sample was also discover to be improved when the using of CFRP bar as a longitudinal reinforcement ratio. In supplement, the maximum load of the continuous beam was decrease when using GFRP bar as a longitudinal reinforcement ratio.
Preliminary mechanical characteristics of asphalt concrete mixture containing RAP as the design of sustainable mixture
Authors: Kareem Yassir N. A. , Al-Jumaili Mohammed A.
Published: August 2020

An asphalt pavements require to a wide variety of raw materials, costs and energy in a construction and repair processes. The using of recycled and waste materials in the pavement industry is one branch of the sustainability policy which is leading to substantial reductions in material, cost, and energy, as well as environmental enhancement. This research aims to evaluate the impact of reusing RAP materials in the production of recycled asphalt mixtures and investigate the mechanical characteristics depending on the criteria of mixture strength under affecting various testing conditions as a sustainable design method. Three proportions of RAP materials (12.5, 25, and 50 %) were added to two types of mixtures these used in surface and base layers. one type of softening agent (vacuum residue liquid asphalt) was used to restore the RAP binder properties. Several laboratory experiments were carried out on the control and recycled asphalt mixtures such as Marshall stability and flow, indirect tensile strength and the resilient modulus. The results indicated that the adding of RAP materials with virgin binder resulted in improving the strength and mechanical properties of recycled asphalt mixtures, while the using of vacuum residue liquid asphalt as a softening agent in recycled mixtures has given impressive results in improving the durability and workability.
Effect of Steel Fibers on the Concrete Strength Grade: A Review
Authors: Weli Sardasht S , Abbood Imad Shakir , Hasan Kamalaldin F , Jasim Mohammed A
Published: August 2020

The use of concrete reinforced with steel fibers has emerged as an effective material which has the advantages to be used in the most unconventional situations in reinforced concrete structures. These advantages involve reinforcements in structures that intend to resist loads in extreme conditions or change in the type of use, design and or construction errors, degradation of materials (carbonation or corrosion of reinforcement) and also the possible occurrence of accidents such as fires, floods, gusts of wind and earthquakes. In addition, the increasing use of this reinforcement system requires the development of more conclusive studies regarding the characteristics and behaviour of the steel fibers, as well as a critical evaluation of this material and its techniques. This manuscript presents a review on the interaction between steel fibre and the concrete substrate. Initially, a brief description of some fibers materials is made, followed by a summary of some works on adhesion between steel fibres and concrete under static loads. Finally, a summary of the few works on the main contribution of the steel fibers application to increase the strength after the cracking of concrete matrix during loading.
Experimental study on structural behaviour of branching steel columns
Authors: Khamees Ali Abdulmohsin , Shadhan Khalid K.
Published: August 2020

Few researchers have study the branching column and there is no enough information about it. The objects of this research is to study the structural behaviour of the branching columns and how it effects on the form-finding. These branching columns are experimentally tested and preparation tables to assist with design of it. Experimental work was carried out on the seventeen specimens. All specimens have been tested under static load then evaluated for maximum failure load, maximum vertical displacement and failure mode. The studied variables are the ratio of horizontal spacing between branches to total width of specimen, number of branches and number of branching level. The results showed that when the ratio between the width of the specimen and the overall width was increased, failure load and buckling load was decreased and maximum vertical displacement was increased. When the number of branches increases, the failure load increases slightly, with the vertical displacement increasing. The failure load, buckling load decreased and the vertical displacement greatly increased as the number of branching levels increases. All specimens have failed with buckling mode, and had less failure load and buckling load than the reference specimen.
Experimental investigation of some properties of square concrete-filled steel tubular columns containing iron filings as replacement of sand
Authors: Mhawi A L , Dawood A O
Published: August 2020

This paper presents an experimental investigation of axial load projected onto concrete filled steel tube (CFST) columns and study the effect of using iron filings in the filled concrete mixture to improve the ultimate compressive strength, ductility index and energy absorption. Twelve column specimens was used in this study, three as reference and nine iron filings (CFST) column specimens as a partial replacement of sand by 2.5%, 5%, and 10% with 6 cubics,9 cylinder and 3 prisms samples of concrete of each column specimens. Three types of stub, short and long column. These tests include performing slump, compressive strength, tensile strength and flexural strength. The results show that the concrete with iron filings have the highest compressive strength at the age of 28 days’ageof 49.53Mpa,52,3Mpa and 55.63 Mpa, namely more than control mix by 11%,17% and 25%. However, ductility index and energy absorption of column specimens with iron filings become the highest at the age of 28 days.
Using 2D digital image correlation to investigate the flexural behavior of continuous composite beams
Authors: Abeer S Z , Dawood M B , Ghalib M H
Published: August 2020

This paper aims at studying the flexural behavior of continuous composite beams casting from normal concrete and Slurry Infiltrated Fiber Concrete (SIFCON) by using DIC (Digital Image Correlation) technique. The DIC results are compared with the standard methods measurement. DIC is a new non-contacting and non-destructive optical technique based on digital photographs for the tested area to compare them at different stages of loading. Tests were performed on three full-scale T-section continuous beam specimens subjected to two-point loads. In this paper, the effect of using SIFCON at compression or tension parts of plastic hinge locations on the flexural capacity, moment redistribution and crack width are investigated experimentally. The results indicate that the DIC technique gives very good correspondence comparing with the results recorded by standard methods measurement. In addition, it was found that the enhancement in moment redistribution ratio for the beam with SIFCON at compression parts of plastic hinge zones was significantly higher by about 38% comparing with the beam with SIFCON at tension parts of plastic hinge zones.
Assessment of road infrastructures in Iraq according to safe system requirements: case study Old Baquba-Baghdad rural road sections
Authors: Jameel Abeer , Al-Nuaimi Atheer
Published: August 2020

Safe system is a new vision recommended by global organisation interested in achieving safer road system in the world. Methodologies have been developed to consider this approach in assessing the safety level of new and existing road infrastructures in most of the world countries. In Iraq, most of the conducted studies investigated the road safety level at aggregated national scale. However, there are no studies consider the safe system approach in assessing the road safety situation. Therefore, this paper aims to assess the road safety level at road section scale according to the safe system approach. For this, international methodologies were reviewed to select the most appropriate one. The international road assessment programme (iRAP) was selected as it has been recommended by the UN and WHO. The old Baquba-Baghdad rural road which is a two way-two lane road was selected for this study. The necessary data was collected from a previous study and from field observations, and then was processed using the iRAP programme to quantify the risk scores and the star rating of head-on overtaking crashes for vehicle occupants as this is the most common crashes recorded at the selected sections. The results showed that the star rating of the study road is one to two which reflects the dangerous situation. Therefore, four countermeasures were suggested to improve the level of safety, three of them has been already implemented which are upgrading some sections to four lane road with separated physical median and improving the skid resistance of the road surface. The results of assessment after improvement showed that the implemented improvements may reduce the fatalities rate by about 60% and upgrade the star rating to 3 in some sections and less in others. Therefore, it is recommended to upgrade the two lanes sections to four lanes and extend the physical separation median to all these sections which will eliminate the risk of the head-on overtaking crashes as the results of the assessment produced.
Forecasting of Dissolved Oxygen in Shatt Al-Arab River Based on parameters of water quality Using Artificial Neural Networks
Authors: Khudhur Z A , Dawood A S , Arab S A
Published: August 2020

The quality of water is considered as a vital quality factor that affects the life quality in different areas. Thus, its assessment and forecasting became an essential subject matter for several researches. Analytically, the common adopted feed forward error back propagation neural network technique is used to developed two types of ANN models. The first model is applied having experimental data that gotten from the Department of Environment, Basrah-Iraq, during year 2009-2014 and the data set for the current year (2019), while the second model is applied according to the data for the current year (2019) only. The parameters of input of the neural network are pH value (pH), electrical conductivity (EC), Total Dissolved Solid (TDS), Calcium (Ca), Magnesium (Mg), nitrate nitrogen (NO3), phosphorous (PO4
−3) and Sulfate (SO4
−2), the output parameter of the neural network is dissolved oxygen (DO). Through comparing the outcomes of ANN models depending on high value of regressions coefficient (R2) and lower value of mean square error (MSE). For the first model R = 0.96143 and MSE=0.00125 for testing. The second model is R=0.99225 and MSE=0.00532. The results show the proposed ANN prediction model has a great potential significance for the assessment and forecasting the dissolved oxygen.
Prediction of the contamination track in Al-Najaf city soil using numerical modelling
Authors: Alsamia Shaymaa M. , Mahmood Mohammed S. , Akhtarpour Ali
Published: August 2020

Leachate generated from Municipal Solid Waste (MSW) may drain into groundwater aquifers as a consequence of rainfall, transmitted to the conterminous river system through groundwater flow and contaminate the environment. Iraq, because of the lack of accurate data and the high cost of measurement, accurate assessment of leachate generation levels has often been considered a problem. The production of leachate connects into many factors, such as the data of meteorological, levels of waste production, and requirements of design landfill, the large differences in these factors indicate that leachate modelling processes are complicated. The purpose of this paper is to predict the movement of various contaminants in landfill soil in Al Najaf city to predict the behaviour and distribution of landfill pollution in order to properly understand the distribution of contamination in these soil, to control it and to prevent groundwater contamination to predict the depth of leachate from landfill using numerical model by SEEP/W, and CTRAN/W packages from GeoStudio 2012 Software.
Analysis of abrasion rates in concrete surfaces of hydraulic structures
Authors: Ayoob Nadheer S. , Abid Sallal R
Published: August 2020

Abrasion of water-exposed surfaces in hydraulic structures can impose devastating defects in these surfaces leading to larger costs of rehabilitation and maintenance. One of the possible solutions is the improvement of concrete quality. Generally, several factors govern the abrasion resistance of hydraulic concrete. In the present study, previous experimental works, which carried out depending on the ASTM C 1138 test method, were collected, studied and analyzed precisely in order to estimate the effect of several factors that related with concrete quality on the abrasion rate of concrete. The results showed that the selection of cement type, inclusion of fibers, addition of silica fume and the election of the proper concrete type have the most effective influence among the remaining studied factors on the abrasion rate reduction.
Modified geopolymer paste adhesive bond material for near surface mounted strengthening technique
Authors: Hadi Noor S. , Oleiwi Safie Mahdi , Salman Wissam D. , Ibrahim Amer M. , Mansor Ahmed Abdullah
Published: August 2020

Near surface mounted (NSM) is a promising strengthening technique for improving the flexural, shear and torsional strength of structures. Epoxy is the adhesive material used in this technique, but, the rapid failure happened in the mechanical properties of the epoxy matrix at high temperature, and the dangerous effects of epoxy fumes on the workers made the need of replacing epoxy with a new sustainable adhesive. Geopolymer Paste Adhesive and Modified Geopolymer Paste Adhesive were used in this study as adhesive materials in NSM strengthening technique to be an alternative to epoxy, where the geopolymer is a sustainable, environmentally friendly and less expensive material than epoxy. More importantly, it can better work at high temperatures. The test results showed that the modified geopolymer paste adhesive beat the epoxy adhesive by (4.1)% when adding (1)% micro steel fiber and (9.6)% when adding (0.6)% carbon fiber, while the bond strength reaches to (93)% of epoxy adhesive when adding (0.6)% polypropylene fiber.
Studying The Effect of Internal Sulfates on Normal and Lightweight Concrete
Authors: Naser Maryam H. , Zainab J.K.
Published: August 2020

The current research includes study the effect of internal sulfate (Calcium sulfate) on mechanical properties of normal and light weight concrete. The mechanical properties included compressive, splitting tensile, and flexural strength. The experimental work consists of casting and testing 216 cubes (150×150×150) mm, 216 cylinders (200×100) mm, and 144 prisms (400×100×100) mm having different condition including: ratio of the sulfate, the age test, type of concrete, and type of cement. This research consists of two part normal and light weight concrete, each part divided to three groups according to type of cement (type I cement, type V cement, and type I cement with 15% silica fume replacing from weight of cement). Each group consisting of four set with different ratio of sulfate (0.28% (reference SO3), 0.5%, 1% and 1.5%) by weight of fine aggregate where these ratios approximate the actual reality of the sulfates present in internal concrete components such as sand, each set having nine cubes tested in a different age (28, 60, and 90) days. The experimental results show that the harmful effect of internal sulfate in concrete on mechanical properties was decreased by using type I cement with 15% silica fume replacement whether normal and light weight concrete. Using of silica fume concrete is more effective to enhance the concrete resistance to internal sulfate attack.
Investigation of the behavior of shallow machine foundation resting on a saturated layered sandy soil subjected to a dynamic load
Authors: Karim H H , Samueel Z W , Hussein M A
Published: August 2020

In liquefying soils, Shallow foundations may experience an increase in settlement and displacement due to dynamic loading. Therefore, the machine footing may settle and tilt excessively. In this paper, the settlement of shallow foundation and inner displacement on liquefiable of unreinforced and reinforced saturated multi-layered sandy soils (medium-dense sand MD) will be studied. The relative density of the first and second layers is 50% and 85% corresponding to medium sand soil and dense sand soil respectively. The tests have been carried out on 20 models. The amplitudes of the applied harmonic load are 0.25, 1 and 2 tons with frequencies of 0.5, 1 and 2 Hz. The used foundation was with dimension 200*200*20 mm and the geogrid was used as reinforcement material. For each amplitude and frequency of load, the sand models were tested without and with reinforcement in various configurations (0.5B, 1B using single reinforcement layer and 0.5B, 1B using double reinforcement layers) where B is the square footing width. The results showed the high susceptibility for liquefaction and its potential which increased with increasing amplitude load and amplitude frequency. Also, the surface settlement and displacement were increased in the first layer and reduced with increasing relative density. The results also showed the high effect of reinforcement material and its configuration and number of layers by maintaining the little settlement values when fixing other parameters.
Rural traffic characteristics using field data and the developed simulation model
Authors: Al-Jameel Hamid Athab , Kadhim Ali Jihad
Published: August 2020

This study has mainly focused on studying the characteristics of selected rural roads in Iraq using the developed simulation model and S-Paramics in order to enrich the area of developing such traffic simulation model calibrated with field data. Thus, several sites, such as Baghdad-Hilla, Baghdad-Mahmudiyah, Baghdad-Kut, Baghdad-Diyala and Najaf-Kerbala, have been investigated such as two and three-lane sections. This paper has three objectives; first, to investigate driver behavior mostly according to collected data of lane changing, lane utilization, flow and time headway. The second objective is to develop simulation model starting from car-flowing and ending with the process of calibrating it graphically and statistically with field data. The third objective is to calibrate the well-known S-Paramics model with field data and comparing it with the developed model. More than 80hrs have been collected using video cameras placed on footbridges as vantage points. The graphical and statistical analyses demonstrate more accurate for the developed model with field data than S-Paramics model. This model may be considered as the first step towards modeling driver behavior in Iraqi rural roads and enhance this model to represent different behaviors according to the collected data.
Civil construction wastes and influence of recycling on their properties: a review
Authors: Odaa Sief Aldeen , Mohd Noor Azline , Derea Abeer T
Published: August 2020

Failures in the management and planning processes for waste disposal have caused serious urban and environmental problems leading to costly and inadequate management in cities. The lack of areas for waste deposition resulting from the occupation and valorisations of urban areas, the high social costs in waste management, troubles of public sanitation and environmental contamination are some of these problems. With technology suitable for the joint use of recycled construction waste as coarse aggregate, it is intended to reduce the extraction of sand and gravel, and also to reduce the volume of waste landfills. In this manuscript, a review of the bibliography on construction waste and its potential for application in the construction industry is presented.
Effect of using stepped gabions on the distance of the hydraulic jump
Authors: Al-Fawzy Ali M , Al-Merib Faiz H , Al-Mohammed Fadhil M , Hummadi Ali H , Al-Zubaidy Riyadh Z
Published: August 2020

The present study investigates the effect of using stepped gabion weir in a laboratory channel on the distance of the hydraulic jump. A set of 25 laboratory experiments and 175 operation tests were conducted using a laboratory flume with dimensions 10 m long by 0.3 m wide, and 0.5 m high. The tested gabion weir had different five possible lengths 0.88 m, 0.96 m, 1.04m, 1.12 m, and 1.20 m, and the filling material used was natural quarry mono graded gravel in five different sample sizes of average equivalent diameter 11.75 mm, 16.50 mm, 22.00 mm, 31.25 mm, and 43.75 mm. Operation discharge values ranged between 0.7 to 15.0 l/s. The data set was subject to dimensional analysis to generate dimensionless groups, and correlated using the Buckingham Pi-Theorem. The results of this study showed that in case of direct representation between the parameters, the distance of hydraulic jump has a direct relationship with discharge but both the gravel sample used and the overall length of the weir give an undular behaviour with its increment. While using of dimensional representation shows that both the gravel sample and weir length have an inverse relationship with the distance of the hydraulic jump. Many trials have been made to formulate the best equation which combine the studied parameters with good agreement.
Strengthening the clayey gravel and sand soils for Subbase course highway using different waste materials
Authors: Kadhum Raghda Kamil , Aljumaili Mohammed Abbas
Published: August 2020

The stabilization of clayey gravel and sand soil used in construction of subbase course pavement highway is one of the engineering solutions in order to increase structural capacity of underneath pavement layers. There are many sorts of soil stabilization which are classified into mechanical and chemical methods. Recently, there has been an increasing social concern about the issue of waste management, by production industrial waste and waste disposal. This project presents the study of the influence of waste ceramic dust (WCD) on strength of clayey gravel and sand materials used in construction of subbase course. The subbase collected locally was mixed with waste ceramic dust from (0 to 25%) by weight of dry soil. The target of this study is to clear that waste is often used as filling and reinforcement and for this reason California Bearing Ratio test (CBR) was conducted to research the strength of waste ceramic and plastic strip of subbase material. The application of plastic waste in various forms is one among the emerging areas of ground improvement technique and there are economic and eco-friendly advantages. A detailed analysis of their results depicts that it is often utilized in the fields effectively and economically as reinforcing materiel. Plastic strips with dimensions (12 mm × 6 mm) are mixed with soil containing the optimum proportion of ceramic dust and California bearing tests are conducted. The effect of waste plastic strip (WPS) content is 0.5% to2% (by weight of sub base material) on the CBR of strip reinforced subbase was studied. The ratio is decided by changing its length and width. From the CBR on soil with and without plastic reinforcements, it had been found that after reinforcement the soil gained its strength appreciably. The best percent of waste ceramic dust was (20%) with waste plastic strip is (1%) which gave higher percent of CBR.