SUMMARY This research work includes three main experimental stages. The first stage includes the production of foamed concrete. It is divided into two parts; in the first, mixing design (determination of the proportions of the raw materials) according to the required density was presented and in the second part, the mixing procedure has been illustrated. The second stage includes preparation of samples,(i.e. molding, finishing surface, removal from molds and curing). The third stage includes several tests to estimate properties of the final product and factors influencing them . These properties include density , compressive strength , splitting tensile strength and flexural strength. For foamed concrete with 800 kg/m3 density, the 28-day compressive strength is from (1.334 MPa) to (2.323 MPa), while with 1600 kg/m3 density, the strength is from (7.015 MPa) to (9.591 MPa). For 1600 kg/m3 density foamed concrete, the 28-day flexural strength range is from (1.08 MPa) to (2.205 MPa).
ABSTRACT This research models the relationship between traffic characteristics and lane position on a six-lane divided highway. Both macroscopic and microscopic models were developed to analyze speed-density, speed-flow, and flow-density relationships for each lane, using linear and nonlinear approaches. Additionally, microscopic models were created to investigate speed-spacing, speed-headway, and headway-spacing relationships. Data was gathered using video recordings and radar speed guns, and traditional methods were applied to calculate density and spacing distance, which are typically challenging to measure in the field. Microsoft Excel and SPSS ver.26 software were utilized for analysis. The coefficient of determination (R-square) and the chi-square test were employed to assess the goodness of fit for the models. The results indicated no significant differences between the predicted and observed data, demonstrating critical traffic characteristics and providing insights into vehicular and driver behavior. These models can be utilized to identify various parameters of traffic characteristics in future studies on the examined highway.
Concrete is by far the most widely used construction material now today. Foamed concrete is light building material with good strength as well as low thermal conductivity and easy workability; it is produced by either Mix Foam Method or Preformed Foam Method. Ultrasonic Pulse Velocity(UPV) is a non destructive technique involve measuring the speed of sound through concrete in order to predict concrete strength and to detect the presence of cracking, voids, decay and other damages. This research includes three main experimental stages:- The first stage includes the production of foamed concrete and it was divided into two parts, the first part, mixing design(determination the proportions of the raw materials) was presented in the second part, the mixing procedure has been illustrated. The second stage includes preparation of samples,(i.e. molding, finishing surface, removal from molds, and curing). The third stage includes several teste to estimate properties the final product and factors influencing them, these properties include density, compressive strength, and the ultrasonic pulse velocity. From the experimental work and at the same test's age, the compressive strength and the ultrasonic pulse velocity for foamed concrete with 800 kg/m3 density were respectively (2.38 MPa,1.56 km/s)and the compressive strength and the ultrasonic pulse velocity for foamed concrete with 1200 kg/m3 density were respectively (3.7 MPa,1.96 km/s) while it were (7.8 MPa and 2.12 km/s) for foamed concrete with 1600 kg/m3 density
This research paper is accomplished to study the effect of using waste fibers in properties of concrete . Steel lathe waste fibers are added by percentages of (4, 6 and 8 %) from weight of concrete and a percentages of concrete coarse aggregate are replaced by rubber tires waste fibers in a ratios of (5, 10 and 15%) by volume . Besides to that, the combined fibers are used steel lathe waste fibers by adding (4, 6 and 8 %) with constant replacing of rubber tires waste fibers of (10 %). The results showed that adding of steel lathe waste fibers in plain concrete enhances its strength under compression about (15%) and tension about (20%), while rubber tires waste reduced both of compression about (80 %) and tension about (51%) strengths .Also the compression and tension strengths are reduced (88% and 30%) respectively with using combined fibers . The dry concrete density of lathe waste fibers concrete is (2345-2365kN/m3) , the rubberized concrete density is (2130-2240kN/m3) and for combined fibers concrete density (2025-2180 kN/m3).
In this study the behavior of rectangular footing on gypeous soil was studied under inclined and eccentric loading. The experiments were performed using laboratory scale rectangular footing rested on soil taken from Tikrit University site in Salah Al Din province under 3 m depth which has a gypsum content of (50.48 %). The load test was performed on rectangular footing at eccentricity of (e/B= 0, 0.1, 0.2 and 0.3) and an angle of inclination of the load with the vertical ( i= 0°, 5°, 10°, 15°and 20°). The local specifications of the soil are measured (density, moisture, maximum density and optimum moisture content), it is found that that the vertical settlement, horizontal displacement, and base inclination increases with the increasing of eccentricity and inclination of load, the values of bearing capacity that getting in this study was less than of the previous theoretical studies when the load was vertical, and is given a good agreement when load was inclined and field density and moisture of soil. The values of bearing capacity was decreased when the load eccentricity increased because of the effective area became small. It is found that a high settlement occur in footing when a water (unsaturated with gypsum salts) diffuses through the soil, then gypsum become soluble thereby the soil resistance decreases because of rupturing of chemical bond between gypsum and soil.
In recent years, a number of researchers have adopted the wet packing (WP) approach to design different types of concrete mixes. Particle grading is a key to the optimization of the wet compactness density; for that reason, all empty spaces that exist in between large-size particles need to be completely filled with particles of smaller size. Previously-conducted studies in this field have been focused on measuring the particle size distribution’s packing density (PD) of the of granular matrices is the purpose of investigating how to increase the PD of cementitious materials. Thus, literature lacks models capable of predicting the optimal PD value. The current study collected and analyzed 216 datasets in order to construct a model for accurate prediction of PD. The main datasets were organized into two categories: modeling datasets and validation datasets. To configure the model in the best way, a hybrid gravitational search algorithm-artificial neural network (GSA-ANN) was also developed in this study. The findings confirmed ANN as an effective alternative for measuring the ultimate PD of cementitious pastes. ANN provided high levels of accuracy, practicality, and effectiveness in the process of predicting the PD value. Based on the final results, the implementation of the hybrid GSA-ANN technique causes a significant decrease in the number of tests conducted on experimental samples, which results in not only saving time and money, but also reducing the CO2 emission volume.
This research includes studying the possibility of producing a new kind of No-fines concrete by replacing granules of coarse aggregates with grains results from the fragmentation of industrial waste of polystyrene. This replacing were with different volumetric proportions of coarse aggregate, and theses volumetric ratios were equal to (5%, 10%, 15% and 25%). Waste plastic fibers (WPFs) resulting from cutting of soft drinks bottles were added for strengthening this new kind of concrete. Mixing ratio was equal to (1:5) (cement: coarse aggregate) by weight. One reference mix was produced for comparative purpose. Compressive strength, flexural strength and density tests were conducted, it was examined three samples of each examination and taking the average. Compressive strength values of the new sustainable concrete were ranged from 10 MPa to 12.4 MPa at age of test equal to 28 days, while the average value of the density of this concrete at the same age reaches 1930 kg/m3. This average value of modulus of rupture was equal to 2.36 MPa at 28-day age test.
Adding fibers to the shotcrete concrete mixes is very important to increase the load carrying capacity, toughness, and reducing crack propagations by bridging the cracks. On the other hand, this fiber has an effect on the fresh and hardened properties of shotcrete. In this study, fresh properties evaluated by using slump flow, , and segregation resistance tests. Hardened properties included testing of air voids, dry density, water absorption, ultrasonic pulse velocity (UPV), compressive strength, and flexural strength. This works including two types of fibers in three forms (waste plastic (PET)fibers only, polypropylene fibers (PP) only, and hybrid fiber (PET and PP)), each form added by three percentages (0.35%, 0.7%, and 1%) by volume.The results showed that the addition of 1% of all types of fiber has a negative impact on fresh properties. Especially in shotcrete containing waste plastic fiber. Also, all specimens containing fibers showed a decrease in the ultrasonic pulse velocity (UPV) and an increase in air voids and water absorption compared to the reference specimens. Also, the results clarify that the addition of waste plastic fiber to shotcrete led to a slight decrease in dry density. The highest increasing in compressive strength of shotcrete recorded by about 8.2% with using 0.35% PP fiber and highest decreasing was 20.9% with using 1% waste plastic fiber. the highest increasing in flexural strength was 62 with using 1% PP fibers.
1-AbstractThis research includes the variation effect of (W/C) water: cement ratio on the properties as compressive strength , flxural strength , density and workability of concrete contains low Polymer SBR ratio.1:2:4 (cement: sand :gravel) by weight mixes were used . The polymer was added as percentages of cement weight and it was 2%. Reference mix was made. Water cement ratio (w/c) were used are 0.2 , 0.3 , 0.4 , 0.5 and 0.6 respectively and 0.35 (w/c) was used for reference mix . The density of concrete varied between 2030 kg/m3 and 2360 kg/m3.
The aim of this research is to produce lightweight cement mortar with properties better than reference ordinary cement mortar. Porcelanite stone were utilized as lightweight aggregate with a volumetric partial substitution of fine aggregate. The process includes using different percentages (5, 10, 15 and 20 %) of pre-wetted (24hr.) porcelanite to produce lightweight mortar with internal curing. Water curing was used for reference mortar mixture and air curing for the other mixtures of porcelanite substitution. Compressive strength, flexural strength, density and ultrasonic pulse velocity for different ages (7, 14 and 28 days) have been tested. The results show an improvement in the properties of cement mortar especially in replacement percentage of 10 %.
ABSTRACTAn operational analysis is an analytic evaluation of operation on an existing freeway ramps. In this case, all traffic and roadway conditions must be specified. The output of operational analysis is an estimate of the level of service for the ramp in question and of the approximate speed and density at which the traffic stream operations.A ramp is length of roadway providing an exclusive connection between two highway facilities. On freeways, all entering and exiting maneuvers take place on ramps those are designed to facilitate smooth merging of on-ramp vehicles into the freeway traffic stream and smooth diverging of off-ramp vehicles from the freeway traffic stream onto the ramp.The aim of this paper is the operational analysis of ramps on existing 6-lane freeway. This analysis involves the consideration of known freeway of Mohammed Al-Kasim freeway in Baghdad city. Given known geometric roadway conditions and projected traffic conditions, the operational analysis yields an estimate of the level of service and of the speed and density of the traffic stream. This paper has described the procedure for determining the level of service on Mohammed Al-Kasim freeway ramp sections as presented in the Highway Capacity Manual (HCM, 2000). Levels of service are determined for all ramps of the freeway using )HCS2000( software. Level of service of all ramps are similar at AM and PM peak hour periods, because the data was collected under ordinary traffic conditions.
Polyethylene terephthalate (PET) fiber is a green-friendly fiber that is capable of enhancing the mechanical properties of wet-mixing shotcrete. The main purpose of this study is to see how varied volumes of waste plastic fibers (WPF) affect the flowability and mechanical properties of wet-mix shotcrete. For this aim, a variety of experimental tests based on WPF content were chosen. Fresh and mechanical tests included slump, T500, density, compressive strength, and splitting strength were applied. The results shown a improved in shotcrete performance as the WPF content increased. Among all fitting correlations, density and compressive strength revealed the strongest linear ship association. Due to greater interlocking between WPF and concrete matrix, WPF was a major use in enhancing splitting tensile strength. WPF had the most influence on splitting strength, with 23–31 percent, 7–23 percent, and 6–38 percent for 7, 14, and 28-day, respectively.
This study addressed some important tests for concrete including thermal, acoustic insulation and some mechanical behaviour of concrete containing granular Polyvinyl Chloride (PVC) waste as a sand replacement. The PVC waste was collected from a plant of manufacturing PVC doors and windows, was used to replace some of fine aggregate at ratios of 2.5%, 5%, 7.5%, 10%, 12.5% and 15% by weight Properties that studied are thermal conductivity, acoustic insulation slump, fresh density, dry density, compressive strength, flexural strength, and splitting tensile strength. Curing ages of 7, 28, and 56 days for the concrete mixtures were applied in this work. From the results of this study, it is suggested that using of 12.5% fine PVC as a sand replacement by weight can improve thermal insulation to about 82.48% more than concrete without plastic waste Acoustic insulation is about 43.09% more than reference mix and it satisfies the requirement of ACI 213R 2014 for structural lightweight concrete.
In this paper, the laboratory experiments works were conducted to study the effect of adding recycle waste plastic as polyethene terephthalate PET fibers on the fresh properties as the slump test and hardened properties as a compressive strength, splitting strength, elastic modulus, ultrasonic pulse velocity (UPV), density, absorption, voids, flexural toughness and flexural rupture for the normal concrete. The parameter of this paper included percentage of fibers content (0%, 0.5%, 1%, and 1.5%). The geometric design of the PET fibers was a strip with dimensions 4mm width, 70mm length, and 0.035mm thickness. The aspect ratio of the PET fibers in this work was about 50. The results showed that the PET fibers improving the most properties of the normal concrete and on the other hand there is negative effect on some properties of concrete. There is a significant increase in flexural toughness, about 21.2%, while the compressive strength and splitting were increased by 5% and 18.8%, respectively. Besides this improving, using PET fibers conform to the principle of sustainability, which is reducing the pollution and the cost of waste plastic disposal. It’s observed that properties of concrete as a static modulus of Elasticity and density were decreased with the fiber percentage increased
This study was conducted to examine the impact of plastic fibers (WPFs) in an effort to improve some of the features of self-compacting concrete (SCC) using Iraqi raw materials. Waste polyethylene terephthalate fibers (waste PET fibers) from used beverage bottles were added. Some tests were carried out to determine the effects of adding WPFs on the fresh properties of new concrete, while additional tests examined the mechanical properties of hardened concrete. Because of this, self-compacting concrete blends were created with a constant water-to-binder ratio of 0.32 and a binder content of 525 kg/m3. The designated plastic fiber percentages contents were 0%, 0.5%, 0.75%, and 1% of mix volume. Self-compacting concrete mixtures' fresh characteristics were assessed for slump flow diameter, T50 slump flow concurrently, V-funnel flow concurrently, and L-box height ratio. The 28-day density, compressive strengths and flexural strength of self-compacting concretes were also measured. The use of plastic waste fibers had a slight effect on reducing the density of the produced concrete and a negative effect on the fresh properties. The compressive strengths were improved by using WPFs, with the maximum improvement equal to (11.065%) when compared to those made from the reference mix
One of the most popular non- destructive techniques is ultrasonic pulse velocity (UPV) which used in assessment of concrete properties. A statistical experimental program was carried out in the present study to establish an accurate relation between the UPV and the concrete compressive strength. The program involved testing of concrete cubes cast with specified test variables. The variables are the age and density of concrete. In this research, all the samples were tested by direct ultrasonic pulse velocity (DUPV) and surface ultrasonic pulse velocity (SUPV) to measure the wave velocity in concrete and the compressive strength for each sample. An experimental study was conducted to compare between the velocities of ultrasonic waves that transmitted along the two paths; direct and indirect. A total of more than 150 cubes having dimensions of 150 mm side were prepared to conduct both non-destructive and the compressive strength (destructive testing). The results from experimental program were used as input data in a statistical program (SPSS) to predict the best equation, which can represent the relation between the UPV (direct, indirect), and compressive strength, a linear equation is proposed for this purpose. The UPV measurement and compressive strength tests were carried out at the concrete age of 7, 28, 56 days. A relationship curves were drawn between DUPV, SUPV, compressive strength and density. The mixes composition in this study consists of ordinary Portland cement, fine sand, gravel, super-plasticizer, and water. All the specimens were under (20) Cº. The statistical analysis revealed that the possibility in evaluating the properties of the concrete by using direct and indirect wave velocities
Pavement rutting as a permanent deformation is a major type of distress in flexible pavements. In Iraq, the rutting in Expressway pavements represents a severe problem due to its widespread, and high severity and distress density levels. Therefore, driving is profoundly dangerous and causes severe damage to the vehicle’s parts and the life of its riders. To date, the number of comprehensive research on pavement rutting has been limited in Iraq, owing to several technical, logistic, and economic considerations. The current research studies the major mechanisms responsible for rutting and evaluates the structure of the Iraqi Expressway No.1 at selected sections. The work encompasses field and laboratory aspects. The field work involved; performing field surveys to investigate the pavement rutting condition and its extension with depth, characterizing pavement layers in terms of geometric material properties, and collecting field samples for lab tests. The laboratory work was detailed and included; performing a set of standard lab tests on samples taken from the asphalt, the subbase, and the subgrade layers as well as the natural ground. In addition, the project’s archive was searched for specific design information and limitations. In order to assess pavement rutting in the selected sections of Expressway No.1/R9 (A and B), two well-established evaluators were considered; The rutting severity levels and the distress density.
Traffic engineers frequently are engaged in evaluating the performance of different facilities of the highway system. The facility in this project includes freeway section. In design of a freeway, a forecast demand volume is used with known design standards for geometric features and a desired level of service to compute the number of lanes required for the freeway section in question. The design application is straight forward for each usage, but trial-and- error operation analysis may be required to evaluate alternative design. Design requires a detailed traffic forecast, including volumes, peaking characteristics, traffic composition, and specifics of vertical and horizontal alignment for the section under study. The aim of this paper is the design analysis of a freeway with a heavy recreational vehicles. This analysis involves the consideration of three examples of freeways. Given known geometric roadway conditions and projected traffic conditions , the design analysis yields an estimation of the number of lanes and of the speed and density of the traffic stream. This paper has described the procedure for determining the number of lanes of freeway basic sections as presented in the Highway Capacity Manual (HCM, 2000) and HCS2000 software.
The research aims at revealing the morphometric characteristics of wadi Jbab Basin, which include areal ,relief characteristics, and the shapes of cross- sections of the valley. The hydrological properties of Jbab basin were studied to estimate the amount of water received by its catchment area during rain falls, thus, the appropriate places for the construction of dams and reservoirs for use in water harvesting can be determined. The area under study is located in Iraqi western plateau , between the latitudes of 33º 55' 45"N to 34 º 27' 50" N, and longitudes 41º 24' 30" E to 41º 43' 00" E. Remote sensing technology (RS) and geographic information systems (GIS) were used to reach the objectives of this research, so Digital Elevation model (DEM) for the year 2009 was brought to program (Arc GIS 9.3) and detected the basin and valley of Jbab automatically by using the hydrological analysis method. The area under study is characterized by the drought with a deficit of water in all months of the year where the highest in the month of July, amounting to 324.5 mm and the lowest in January, 10.92 mm. The geological formations prevail formations limestone, with sandy soil to sand-clay mixture, with lack of density in the vegetation. The average slope in basin of Wadi Jbab is 0.25 degree. There are five ranks of river, the sum of their tributaries 676 tributary within an area of 986.6 km ², and its perimeter is 214.3 km , it is also noticed the form of the basin tends to form a rectangle, with three places suitable for the construction of dams and reservoirs depending on the morphometric and hydrologic information that related to the area of research.
Concrete is produced from millions of tons of Cement, which emits a significant amount of carbon dioxide from cement mills and contributes to global warming. Therefore, it is important to seek out less expensive and more environmentally friendly substitutes for OPC. While various substitutes are available, such as recycled glass, marble, silica fume fly ash, or agricultural waste like rice husks or wheat straw, the performance of concrete is significantly affected when bentonite is used as a replacement for Cement. This study aims to evaluate Jhelum bentonite, which is located at 32°56′ north and 73°44′ east longitude, as a replacement for Cement in different ratios (0:100, 10:90, 20:80, 30:70, and 40:60) to improve the durability of the system as more bentonite is used to replace conventional Portland cement, the workability, density, and water absorption of the new concrete all decrease. Compressive Strength, Tensile Strength, and flexural Strength of blocks and cylinders were tested after being cured for 7 and 28 days. Analysis of these strength tests revealed that the mixes containing bentonite were weaker after 7 days compared to 28 days, and the Strength of blocks was reasonable compared to cylinders.Keywords: Bentonite, Concrete, Compressive Strength, Tensile Strength.
This study was determined specified characteristics of Iraqi silica sand , touse it in the drinking water treatment rapid gravity filters. These properties includes grain size ,uniformity coefficient , grain shape , porosity , density , durability, chemical content and capability of solubility in the acid ..this study explained that the Iraqi silica sand has high degree at mechanical and chemical stabilities .The e filter column was operate for many cycles , the average results of raw water and treatedwater for variable values (turbidity , total suspended solids and total bacterial count) was taken . The study showed that possibility of use the Iraqi silica sand in the westernIraqi desert in the rapid gravity drinking water treatment plant filters . when the raw water has initial turbidity (5.24 NTU) ,the study and the experimental tests showedthat the average removal efficiency of turbidity , T.S.S ,and T.B.C of (82.9%,82.8%and 79.5%) respectively . when the raw water has initial turbidity (9.58 NTU) ,the study and the experimental tests showed that the average removal efficiency of turbidity , T.S.S ,and T.B.C of (79.4%,78.7% and 74.1%) respectively . when the rawwater has initial turbidity (28.35 NTU) ,the study and the experimental tests showedthat the average removal efficiency of turbidity , T.S.S ,and T.B.C of (72.6%,72.7%and 60.9%) respectively
There are various means of recycling agricultural wastes to maximize economic benefit from it. According to environmental statistics, agricultural wastes is one of the most dangerous types of wastes, especially in villages, because it is disposed of by burning. In this study, production of natural ash from agro wastes was carried out. Two types of agro waste ash were produced through burning and grinding process. waste date tree and waste reeds ash. The waste date ash (WDA) and waste reeds ash (WRA) were included in concrete by replacement of a specific portion of cement weight (5%, and 10%). Moreover, a blend of the two types of ashes were also considered. Furthermore, the natural ash was utilized in production of green concrete. Hardened density and compressive strengths at various ages (7, 28 and 56 days) were evaluated. The results in this research showed an excellent increase in compressive strength at ages (7,28 and 56) days. When measuring the compressive strength at the late age (56 days), DPA + WRA it was the best model used if it recorded the highest increase in it. Also, the use of WRA10% gave a good result, increasing its strength of the reference mixture and the rest of the mixtures also gave good and remarkable results in increasing the resistance, as the use of ash in these mixtures protects the environment from pollution and gives mixtures of higher resistance and can be used as a partial substitute for cement, except for DPA10%, so the usual mixture was better than it.
The researches in Iraq has expanded in the field of material technology involving the properties of the light weight concrete using natural aggregate aviable in westran of Iraq. Researches work on porcelinite concrete has been carried out in several Iraqi Universities. The study is deals with mechanical properties of porcelinite aggregate concrete by casting (273) different specimens. These properties are, compressive strength, flexurale strength, splitting strength, static modulus of elasticity and absorption. The results indicated that the structural light weight aggregate concrete produced from local porcelinite aggregate is suitable to used as a structural concrete, it can produce structural light weight concrete of compressive strength varies from (23.0 to 29.8) MPa with the density ranges from (1745 to 1855) kg/m3, by using cement content about (550 and 650) kg/m3.Such concrete exhibited good mechanical properties. It gave the values of splitting tensile strength, modulus of rupture and modulus of elasticity, 75%, 90% and 60% from those of normal weight concrete respectively owning the same compressive strength and meeting the requirement of ACI-213
This research includes study the effect of fineness upon physical properties of cement mortar where use ordinary Portland cement with fineness (300 m2/kg) as reference mixture which denoted by symbol (M1), and then produce with flowing fineness (350,400,450 and 500 m2/kg) which denoted by ( M2, M3, M4, M5 ) respectively . The results of study show that increasing in fineness makes an increase in water quantity that requires for consistence of standard paste and the ratio of above mixes with reference mixture (2%,5%,7%,11%)respectively, although the increasing in density for all ages and increasing in compressive strength in early age, the increasing ratio in 3 days age was ( 45% , 50% , 60% , 70%)respectively .this increasing in fineness makes increasing in ratio of flow as compared with reference mix(16%, 25%, 50%, 66%) respectively
The aim of this study is to develop Lightweight self-compacting concrete (LWSCC) mixtures using locally sourced waste materials such as Expanded Polystyrene Beads (EPS) and Waste Plastic Fibers (WPFs) which are all available abundantly available in Republic of Iraq at little or no cost. The fresh, hardened and mechanical properties of these LWSCC were studied, followed by results analysis. Five different mixes of LWSCC were prepared in term of WPF content (0.25, 0.5, 0.75, 1.0, and 1.25 %), in addition to the control mix (R mix) and lightweight concrete (E mix) made of EPS content as a replacement of coarse aggregate. The study showed that the LWSCC produced with these waste materials were decreased the density (lightweight) of the concrete mixes as EPS tend to form more clumps, absorb water and make the mix dry. Therefore, concrete mixtures were adjusted accordingly to be able to offset the workability caused by the addition of EPS. The increase in WPF content decreased the workability due to clumping that occurred in the mixing phase. The analysis of mechanical properties of the LWSCFRC specimens revealed that there was not much improvement. While LWSCC with 100% of EPS replacement as coarse aggregates and 1.25% WPFs provides the best flexural toughness performance
Abstract:-This investigation studies the mechanical characteristics of carbon fiber reinforcedlight weight aggregate concrete, containing different percentages of fiber. The effect ofusing high range water reducing agent (SP) with 8% silica fume (SF) and 8% highreactivity Metakaolin (HRM), as a partial replacement by weight of cement, on thebehavior of (LWA) concrete is also studied.This investigation was carried out using several tests. These tests were workability freshand hardened density, compressive strength, splitting tensile strength and modulus ofrupture. Tests were performed for specimens at ages of (7,28,60,90 and 180) days . Thetest results indicated that the inclusion of carbon fiber to the light weight concrete mix didnot affect the compressive strength significantly, while the splitting tensile strength andthe modulus of rupture were improved significantly. The addition of silica fume andmetakaolin improves the compressive, splitting tensile , and modulus of rupture strengthsof carbon fiber light weight concrete. The average improvement was about (26.5%, 71%and 73 %) respectively for carbon fiber LWA concrete containing silica fume and (28%,72% and 75%) respectively for carbon fiber LWA concrete containing high reactivitymetakaolin.
This study presents an investigation of the mechanical properties of normal concrete reinforced with discarded steel fibers (DSFs) resulting from tire manufacturing. DSFs were added to concrete in two different volume fractions of (0.25 %, and 0.5 %), and these fibers have dimensions of (40 mm length×0.92 mm diameter). The results showed that the compressive strength of the concrete was enhanced by (8.8%, and 3.3%) by adding of DSFs. However, the workability of concrete decreased at all added ratios. While the density is slightly changed. Also, the results indicate that the modulus of elasticity shows slight increases by (3.06%, and 2.25%). Additionally, the incorporation of DSFs improves the splitting tensile strength and modulus of rupture significantly. For concrete mixes having volume fractions of 0.25% and 0.5%, the splitting tensile increased by (7.89%, and 23.68%), and the modulus of rupture increased by (6.67% and 25.58%), respectively. It was concluded that using this type of discarded fibers can improve the mechanical properties of concrete as an alternative type for other types of industrial fibers.
Multilane highways typically are located in suburban communities, leading into central cities, or along high-volume rural corridors connecting two cities or significant activities that generate a substantial number of daily trips. The objectives of the present study include the analysis, and evaluation the level of service (LOS) on section for multilane highway in Ramadi city. The LOS multilane highway is based on density, which is calculated by dividing per lane flow by speed. The required traffic and geometrical data has been collected through field surveys on the section for multilane highway. Traffic volume data were collected manually and classified by vehicles types during each 15 minute interval. Highway Capacity Software 2000 (HCS 2000) program is used for the requirements of traffic analysis process to determine the level of service. It has concluded that the level of service on selected section for east bound is (A), and for west bound is (B).
Abstracte: The stress-strain behavior of any type of soil depends on a number of different factors including density, water content, structure, drainage conditions, strain conditions (i.e., plane strain, triaxial), duration of loading, stress history, confining pressure, and shear stress. In many cases it may be possible to take account of these factors by selecting soil specimens and testing conditions which simulate the corresponding field condition. Even when this can be done accurately, however, it is commonly found that the soil behavior over a wide range of stresses is nonlinear, in elastic, and dependent upon the magnitude of the confining pressure employed in the tests. In order to perform stress analysis of soils, it is desirable to employ techniques, which account for these important aspects of soil behavior.
This research work includes production of new type of light weight concrete and studies the mechanical and thermal properties. Several proportions of raw materials were used to produce this type of concrete. This study is intended to produce light weight concrete with low thermal conductivity so that it can be used for concrete masonry units. Polystyrene aggregate was added as percentages by weight of cement to improve the thermal properties of this type of concrete .Mechanical , and thermal tests with difference ages were made in this work .For polystyrene concrete with polystyrene cement ratio (p/c) of (2.67 – 6 )% , the28-day compressive strength range is from (4.31 – 2.67)MPa, flexural strength range is from (3.05-1.719 ) MPa , density range is from ( 1493-1213 ) kg/m 3 ,and thermal conductivity range is from ( 0.91-0.782)% as a percentage by that of reference mix. The study show suitability of this type of concrete to be used in concrete masonry units of non-bearing walls.
This research aims to study sediment discharges in Al Anbar Thermal Power Station in two phases the first phases include a follow-up study sediment load from the river by taking samples at different depths and different discharges, and noted measurements, calculations for each section while the second phases included an account of the tonnage of river sediment through the program depends on the equation of Meyer, to five sections (18, 26, 35.43, 45) with the observation results and do a comparison between the two phases. Research has included also employ technology of remote sensing and geographic information system GIS in the study of the waters of the Euphrates at thermal power plant after an analytical study was taken amount sediment and size in the study area and then link results with the geographic information system GIS for the purpose of producing layers represent the nature of the spatial distribution of these Sediments on the entire study area and the aerial imagery of software Google Earth with the use of the program (Arc view), one of the geographic information system software. The research concluded give recommendations for controlling the movement of sediment when the at Al Anbar Thermal Power Station Outlet through two main axes of them increase the flow velocity exceeds the critical velocity and the other includes the disposal of sediments away from the site of the station outlet.
Foamed concrete (FC) is a type of lightweight concrete characterized by a high void space ratio and cementitious binders. In this research, the fresh and mechanical properties of fiber-reinforced modified foamed concrete (made with fly ash, silica fume, and superplasticizer) with a density of 1300 kg/m³ were studied. Carbon fibers of different lengths (12 mm, 20 mm, and 28 mm) were introduced in two ways: as single fibers (12 mm) and as hybrid fibers combining lengths of 20 mm and 28 mm.
The results showed that the compressive and split tensile strengths increased by approximately 43% compared to the control mix (modified with additives) when using a single fiber of 12 mm at a volume proportion of 0.4%. In contrast, using hybrid fibers resulted in increases of about 65% and 66% in compressive and split tensile strengths, respectively. When compared to the single fiber method, the hybrid approach improved compressive and split tensile strengths by about 15% and 16%, respectively.
Abstract :- For improving the properties of asphaltic cement several materials such as sulfur, rubber, carbon black, polymers….etc. are used for this purposes. In this study low density Polyethylene (LDPE) used at different percentage (0%, 1%, 3%, 5% and 7%) by weight of the asphaltic cement and then the changes in the properties are evaluated by pentration test (ASTM D-5), softening point test (ASTM D-2398), and Kinematics viscosity test (ASTM D-2170). Temperature susceptibility was evaluated by using Penetration vescosity number ( P.V.N ). In addition to that stiffness modulus of asphalt cement was predectied by using van der pole’s nomograph. The study showed that the LDPE increase the hardening of asphalt cement at different percentage except at (1%), and decrease the susceptibility of asphaltic cement to temperature.
Constructing and testing a microbial fuel cell, (MFC) was accomplished in this research. Two chambers MFC connected with salt bridge was operated and studied using synthetic and real wastewater as anode chamber solution. Operating temperature and pH value were investigated by changing temperature from 25 OC to 30 OC and varying pH from 6.7 to 6.5. The results reveled that increasing operation temperature had a significant effect on reducing operation time while decreasing pH improved the measured voltage and current besides reducing operation time to just five days. The cell was tested with the presence of real wastewater under the optimal temperature and pH and the results proved the capability of the manufactured cell in treating such contaminate in relatively short operation time. The COD reduction rate was above 60% indicated the ability of living microorganisms in digesting the wastewater producing electrical power with maximum values of 0.443 mV and 8.3 μ A for voltage and current, respectively.
This study is the second stage of the paper “Study the Effect of Rubber Silicon on Physical Properties of Asphalt Cement”. This study took the effect of additives on asphalt mixture performance. Asphalt mixture has been designed by Marshall method for determining the optimum asphalt content and geophysics properties of mix according to ASTM (D- 1559 ). Rubber silicon at different percentage (1%, 2%, 3% and 5%) was added to asphalt binder and three specimens of asphalt rubber silicon mixture (ARSM) are prepared and evaluating according to Marshall method. Diametric tensile creep test ASTM (D-1075) at 60 Co used to evaluating permanent deformation and modulus of elasticity for ARSM. The study shown that the Rubber-Silicon has more effects increasing the marshal stability, air voids, and reducing the flow and bulk density compared with the original mix.. Increase the flexibility properties of the mix and this appear from reducing the permeate deformation at test temperature (60C), the reduction percent is about (30 to 70)%