ABSTRACT The rapid development in computer Technology and in the instruments used in field measurements helped to overcome the problem of accuracy improvement and accuracy assessment of high precision networks. This paper deals with solution of the use of mixed observation systems, it is an essential requirement to improve the accuracy. The study of the magnitude of the correlation of error is of great importance in the efficient performance of planning, measuring and adjusting operation of survey. This paper concludes that the use of weights for mixed observation constitutes an important part in the improvement of the accuracy of a micronetwork. Weights which are determined for mixed observation after the assessment of the standard error of unit weight for each kind of observation .
Ferrocement is a type of concrete made of mortar with different wire meshes. It has wide and varied applications in addition to its strength and durability. This research aims to combine ferrocement and sustainability, as over time, the consumption of plastics, especially plastic bottles, has increased and has serious negative effects if buried, burned, or chemically analyzed. Therefore, this research aims to benefit from this plastic waste and introduce it into the construction field by using plastic waste fibers in the concrete mixture instead of cement at a rate of 0.5% and 1% by volume. This research studied the mechanical properties of nine samples of ferrocement beams with dimensions of 1200 × 200 × 150 mm3. A longitudinal hole with a diameter of 50 mm was drilled in different places of the beams and filled with lightweight concrete to facilitate the use of the hole in service passes when drilled, with a study of the initial cracking loads and the resulting deflection in addition to the failure modes and the deflection resulting from the maximum load. The results showed an improvement in load resistance with an improvement in deflection at the maximum load, In addition to an increase in the improvement of Toughness and Stiffness of ferrocement beams.
Organic soils are problematic soil for various engineering applications due to their high compressibility and low shear strength which need to be improved. For many soil improvement techniques, using waste materials, such as fly ash (FA), is a practical and sustainable process. In this research, FA and geopolymer were used e used to reduce organic soil's compressibility. A one-dimensional consolidation test was performed to evaluate the organic soil's consolidation and compressibility properties. The geopolymer was prepared using 20% FA and of sodium hydroxide ratio and sodium silicate alkali solutions. The geopolymer specimens were first cured for 2 hours at 45 and 65 oC, then cured for further 28 days at room temperature. The consolidation test results showed that FA-based geopolymer is effective in stabilizing organic soils due to the observed improvement in the compressibility, consolidation, and permeability characteristics. The compression index decreased by 98.16%, and the permeability decreased by 95%.
Abstract The rapid development in computer technology helped to overcome the problem of accuracy improvement and accuracy assessment of high precision network. In this paper a study was conducted to evaluate and compare the accuracy of position through the area of error ellipses in case of using single base line and two base lines for geodetic monitoring network of Haditha Dam . The present paper purpose is to conclude that the use of additional baseline is an important part in the improvement of micronetwork accuracy and treats the weakness in the geometrical figures used.
Abstract The rapid development in computer technology helped to overcome the problem of accuracy improvement and accuracy assessment of high precision network. In this paper a study was conducted to evaluate and compare the accuracy of position through the area of error ellipses in case of using single base line and two base lines for geodetic monitoring network of Haditha Dam . The present paper purpose is to conclude that the use of additional baseline is an important part in the improvement of micronetwork accuracy and treats the weakness in the geometrical figures used.
The use of textile reinforcement made from non-corrosive materials, such as carbon and glass can reduce the required concrete material; this is known as Textile Reinforced Concrete (TRC). This study deals with plate specimens having dimension of 500×500×40mm tested under impact load at 28 and 90 days age under two conditions of ends, simply supported and fixed. Cement mortar with about 60 MPa, 7cm cube compressive strength at 28 days was designed for casting the plates. Plate specimens were divided into four groups, they consist of reference plates (no reinforcement) and plates reinforced with 3D glass fabric having three different thicknesses 6, 10 and 15mm. The results indicate that using 3D textile glass fabric cause an increase in number of blows, reduce in final stage deflection, an improvement in toughness and energy absorption under impact loads. Using 3D textile glass fiber with 10mm thickness gave higher number of blows for 28 and 90 days as compared with 6 and 15 mm. Plates with slice 6mm 3D textile glass fiber in two way reinforced has significantly enhancement in number of blows, the improvement was about (80 - 125%) and (128.5- 114. 3%) for 28 and 90 days respectively. The specimens showed increase in the energy absorption, besides the number and width of cracks was reduced and only few cracks are propagated up to the edge of the plates.
This research investigates the impact resistance of concrete slabs with different volume perecentage replacement ratios of waste plastic fibers (originaly made from soft drink bottles) as follows : 0.5%, 1% and 1.5%. Reference mix produced in order to compare the result. For the selected mixes, cubes with (100×100×100mm) were made to test compressive strength at age of (90) days. Flexural strength (Modulus of Rupture) test was also conducted using prisms sample of (500*100*100 mm) dimensions. The low-velocity impact test was conducted by the method of repeated falling mass where 1400gm steel ball was used. The ball falling freely from height of 2400mm on concrete panels of (500×500×50 mm) having a mesh of waste plastic fiber.The number of blows that caused first crack and final crack (failure) were determined, according to the former obtained results , the total energy was calculated. Results showed an improvement in mechanical properties for mixes containing plastic fibers compared with reference mix. For compressive strength the maximum increase in compressive strength was equal to (3.2%) at age of (90) days. Flexural strengths for mixes containing plastic fiber at ages 28, and 90 days are higher than that of these of reference mix. The maximum value of increaseing was (18%) for 28 days age of test and it was equal to (26%) for 90 days age of test for the mixture with plastic fiber content by volume equal to (1%) . Results showed a significant improvement in low-velocity impact resistance of all mixes contining waste plastic fibers when comparing with reference mix. Results illustrated that mix with (1.5%) waste plastic fibers by volume give the higher impact resistance at failure than the others. The magnitude of an increase over reference mix was equal to (340%).
A study examined the ductility and toughness properties of beams made of reinforced concrete, including foamed, normal, and hybrid beams. Nine reinforced concrete beams were produced: three foamed concrete beams, three normal concrete beams, and three hybrid concrete beams. Each beam possessed identical rectangular cross-sectional dimensions of 1500 mm × 250 mm × 150 mm. The flexural parameters (ultimate load, ductility, deflection, and durability) were assessed for each type of concrete utilized. The study's results showed that the load-bearing capacity of hybrid concrete beams was comparable to that of normal concrete beams, whereas foamed concrete beams exhibited slight improvement in their ability to carry loads. The ductility of reinforced foamed concrete beams was lesser than that of normal concrete. For over-reinforced beams, the ductility of hybrid concrete beams showed a significant improvement of 61% compared to foamed beams and an even more significant increase of 91.7% compared to normal beams. Furthermore, the hybrid concrete beam with over-reinforcement had a flexural toughness of 18.7% greater than the normal concrete beam. Suggested that a hybrid section comprising conventional and foamed concrete be utilized to decrease ductility and improve stiffness.
Abstract :The intersections "roundabout" is an important part of the highway system. Theoperational efficiency, capacity, safety and cost of the system depend largely upon itsdesign of intersection "roundabout", especially in urban areas.The objectives of the present study include the analysis, evaluation and improvement theoperation traffic of selected roundabout (Kahtan Square) in Baghdad city by analysis anduse many alternatives to improve the roundabout (Kahtan Square) operation under localexist conditions and to present a best proposal to enhance the performance at the requiredfacility.To achieve these objectives, the traffic volumes data collection and geometric layout forKahtan square that required for the traffic and geometrical analysis were gatheredmanually, while SIDRA traffic program is used for the requirements of traffic analysisprocess.It has been concluded that, fly over at the main path of traffic movement at kahtan square(Baya'a – Yarmok hospital) is the best proposal to improve the capacity and trafficoperation for kahtan square.Keywords: Traffic operation, Round about, Level of service, Capacity
Capacity and level of service are the control points of the analysis of intersections and must be fully considered to evaluate the overall operator of the intersection. The objectives of the present study include the analysis, evaluation and improvement of the operation for Stadium Intersection in Samawah city and to present the best proposal to enhance the performance from the capacity point of view. To achieve these objectives, the estimated distribution of the traffic data in different directions that required for the traffic and geometrical analysis were gathered manually, while HCS traffic program is used for the requirements of traffic analysis process. It has been concluded that the flyover between Al-Zwaid Street – Stadium Street (Proposal No.5) is the best proposal to improve the operation ability of Stadium Intersection.
This study concern with a new technology to modified the compressive strength of the thermo brick which have a main role in construction field. This research using a new local cheap additives called (tar) which is available in Iraq (Kirkuk area). The experimental program have include three type of thermo brick available in local market (Iraqi, KSA, and Kuwaiti) and these type are common used in south area of Iraq especially Basrah City. The sample has exposed to the steam of tar in different temperature. Four affecting factor are studied carefully on compressive strength of brick including, tar , brick manufacture type, number of exposing faces of brick, and the age of brick after finishing expose of brick to the tar steam. The result shows maximum compressive strength conducted are 4.4 MPa when two faces expose to tar and two hours’ time of exposing ( one hour for each face) and the modified percentage was 62% compared with reference sample (KSA type). The improvement in compressive strength of Iraqi type and Kuwaiti were 27% and 45% respectively. Furthermore the improvement of compressive strength with same condition aforementioned but for one hour exposing time (half hour on each face) are 37.5%. The chemical properties also has conducted in this study.
This study investigates the strength performance and microstructural changes of a sandy gypseous soil improved with fly ash-based geopolymer, for shallow and deep applications. Different proportions of geopolymer were added to a natural gypseous soil having a gypsum content of 30% to 40% with different water contents. The fly ash was activated using sodium hydroxide with molar concentrations 8 and 12 molar and sodium silicate. The ratios of the fly ash to the activator were 1 and 2. Specimens were cured for different ages at 30°C. To simulate the field conditions, a number of specimens were immersed in a salt-saturated solution. Materials performance was evaluated at the macro level by performing unconfined compression test and at micro level by performing scanning electron microscopy test. The study showed that an increase in the molar concentration of sodium hydroxide and of the binder ratio improved material’s strength particularly at lower water contents of the soil. Increasing the binder content to about 30% improved the strength by enhancing the bonding between the soil particles. On the other hand, immersing the samples in the salt solution led, in most cases, to breakdown of the geopolymer network, as confirmed by the SEM images. It was concluded that the fly ash geopolymer-soil mixtures under investigation can provide as high as 8 MPa uniaxial strength under no sulfate attack. However, under sulfate attack condition, this strength can decrease to as low as 0.5 MPa. Even under the worst case, the later strength can be just enough to support shallow foundations rested on a saturated gypseous soil.
This research includes the study of improving impact resistance of concrete using styrene butadiene rubber (SBR) with different weight ratios of polymer to cement 3%, 5% and 10%. Two series of polymer modified concrete (PMC) were produced the first level I with moderate compressive strength and the other level II with higher compressive strength. Cubes, prisms and panels were made as follows: Results showed an improvement in impact resistance of polymer modified concrete (PMC) over reference concrete in low-velocity and high-velocity impact properties. In conducting low-velocity impact tests, method of repeated falling mass was used: 1300gm steel ball falling freely from three heights 2400mm, 1200mm and 830mm. In high-velocity impact tests, shooting of 7.62mm bullets was applied to slab specimens from distance of 15m. The improvements were significant in low velocity impact resistance. The maximum increases were (33.33%, 75% and 83.33%) at ultimate failure for falling mass heights 2400mm, 1200mm and 830mm respectively. In high-velocity impact strength tests, maximum reductions recorded in spalling area were (18.5% and 27%) for polymer modified concrete (level I) with moderate compressive strength and polymer modified concrete (level II) with higher compressive strength.Maximum reductions recorded in scabbing area were (11.42% and 35.6%) for polymer modified concrete (level I) with moderate compressive strength and polymer modified concrete (level II) with higher compressive strength, 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
Cadastral maps are an important component of land administration in most countries. In virtually all developed countries, the needs of computerized land and geographic information systems (LIS/GIS) has given urgent impetus to computerizing cadastral maps and creating digital cadastral data bases (DCDB). This process is creating many institutional, legal, technical and administrative problems. This desire to establish DCDBs is being given increased impetus due to a new range of enabling technologies such as satellite position fixing (GPS), improved spatial data collection techniques such as digital theodolites and "soft copy" photogrammetry, as well as a vast range of new information and communications technological tools, thus contributing to the advancement and keep up with the great countries. This paper presents the problem of cadastral maps. The hitherto existing cadastre, consisting of paper maps and land registers, is now becoming insufficient. Its shortcomings force developments leading to its improvement. One of the ways is the creation of a Land Information System. A digital cadastral map is the main component of this system. The structure and information content of the map is presented, its differences from analogue maps are shown, and the process of map creation is described. A digital cadastral map can be the basis for additional thematic layers, successively converting it into a complex system for management of administrative units.
The present study, concern about an experimental work to study the stress-strain relationship of steel-fiber reinforced polymer modified concrete under compression. Four different mixes with weight proportions of (1:2:4) were used as; normal weight concrete (NC), polymer modified concrete (PMC) with (10%) of cement weight and two mixes of steel-fiber polymer modified concrete with (1%) and (2%) volume fraction of steel fiber, (SMPC). The influences of polymer and fiber addition on peak stress, strain at peak stress and the stress-strain curve were investigated for concrete mixes used. For all selected mixes, cubes (150×150×150mm) were made for compressive strength test at (28) days while stress-strain test was caried out on cylinders (150 mm 300 mm) at the same age. Results showed an improvement in compressive strength of polymer modified concrete (PMC) over reference mix, the maximum increase of it was (13.2 %) at age of (28) days. There is also an increase in compressive strength with increasing of steel fibers content with comparison to normal concrete, the maximum increases of it were (19.6% and 25.2%) of mixes with 1% and 2% fiber content by volume respectively. In terms of modulus of elasticity, the addition of polymer and the presence of fibers cause a significant increase in it. The peak of stress- strain curve for normal strength concrete (Mix No.1) was linear whereas it was more sharp for the other mixes. The behaviour of normal strength concrete (Mix No.1) was linear up to 20 % of ultimate strength, while for the mixes with the higher strength i.e. polymer modified concrete and fibers reinforced concrete (Mixes No.2, 3 and 4) the linear portion increases up to about 50 % of ultimate strength
Collapse of gypseous soils may cause excessive settlement and serious damage to engineering structures. Various improvement approaches, such as mechanical techniques and chemical additions, have been used to reduce the collapsibility of these soils. The odometer test has traditionally been used to assess the collapsibility of the improved gypseous soils; however, because the small size of test specimens, this method may not adequately reflect field conditions. In this research, a laboratory model test of 600 x 600 x 600 mm with a model footing of 100 x 100 mm was developed to measure the collapse characteristics of a gypseous soil. The top layer underneath the footing was improved by compaction, cement kiln dust (CKD), geogrid, and a combination between CKD and geogrid. The top layer was improved at two values of thickness of 50 and 100 mm. The results obtained from this study indicate that the values collapsibility settlement reduction factor for compacted soil and the soil treated with CKD were 75 and 82%, 89% receptively. These values increased up to 95 % when a combination of CKD and geogrid was applied. As discussed herein, the aforementioned treatment methods can effectively be used to improve the collapsibility of gypseous soils.
The main objective of this study is to evaluate the comparative performance of three artificial neural network techniques (radial basis functions “RBF”, multilayer perceptron “MLP”, and group method of data handling “GMDH”) based approach with the Penman–Monteith “PM” method for determining the group reference evapotranspiration “ET0” on monthly basis in Basrah City, south of Iraq. Climate information extends over 22 years (1991- 2012), monthly records of maximum temperature (Tmax), mean temperature (Tmean), minimum temperature (Tmin), wind speed (U) and relative humidity (RH) are used in this research. The architecture of artificial neural network models is performed during the process of training. The efficiency of trained model is checked by using the testing data, which is not used in the process of training. The evaluating of the artificial neural model performance is carried out by using cross-validation, a set of rows for each validation fold is determined randomly after stratification on the target variable “ET0”. Various set of climate inputs variables are used for creating nine artificial neural network models. The efficiency of artificial neural network models with two predictor variables (Tmean & U) for simulating ET0 is highly efficient according to the evaluation criteria. There is a significant improvement in the results of all artificial neural network models when using three input combination variables (Tmean, U, & RH) compared with the models that have only two-climate variables. Artificial neural network models especially (RBF, MLP, and GMDH) are efficient and powerful techniques for simulating ET0.
AbstractThis research includes the study of the effect of adding steel fibres resulting from cutting chicken wire (which is available in Iraqi markets now) as fibres added to the polymer concrete. These fibres were added with percentages of concrete volumes. These percentages were (0.5%) and (1%). Reference concrete mix was also made for comparative reasons. From the results, it can be noted that the increasing of compressive strength of SFPC1 comparing with RPC at 28 days equal to 9.90%, whereas the increasing of compressive strength of SFPC2 comparing with RPC at 28 days is equal to 15.48%. The increasing of splitting strength of SFPC1 comparing with RPC at 28 days equal to 15.50%, whereas the increasing of SFPC2 comparing with RPC at 28 days is equal to 21.40%. The increasing of flexural strength of SFPC1 comparing with RPC at 28 days equal to 10.80%, whereas the increasing of SFPC2 comparing with RPC at 28 days is equal to 20.63%.Results proved that adding of steel fibres with these percentages lead to improvements in compressive strength, splitting strength and flexural strength of concretes containing steel fibres, but the improvement in flexural strength appeared more clearly. Results proved also an increasing in densities of fibre concrete samples according to these made of reference mix.
The aim of this study is to investigate the effect of adding recycled materials such as CKD and RAP to weak cohesive soils, in addition to evaluate the change in the strength of these soils. This study was conducted on soil type MH, and only RAP particles finer than 10 mm were used in preparing the mixtures. 7, 14, and 28 days were selected as curing periods for soil- CKD and soil- CKD- RAP mixtures to obtain the effect of curing periods on soil improvement. The results showed that adding 20% of CKD to the natural soil increased the unconfined compression strength UCS from 0.43 MPa to 2.6 MPa at a 28-day curing period. Also, the results showed that adding 25% of RAP to the soil- 20% CKD mixture increased the UCS value to 5.3 MPa after 28 days of the curing period. The final results showed that the optimum contents of CKD and RAP added to the cohesive soil were 20% and 25%, respectively, while the optimum curing period was 28 days
Very little attention was given to study learning curves phenomenon in the construction industry, for many reasons related to the nature of production in this industry and also because of the variety of factors which affect these works. This research aims to measure the amount of improvement in the acquired production by the workers on the repeated construction operation because of the experience and learning in Iraq compared with a neighboring country (Syria).The measurement technique involves recording the time required to achieve every unit and finding out the mathematical relation which represents the learning curve for each item of production. The study involves six items (activities) of construction as follows: 1- Ceramic tiles (20 × 20 cm) for walls. 2- Paving the pavement of the street with concrete blocks. 3- Tiling the rooms with mosaic (30 × 30 cm). 4- Building the walls with concrete blocks (20 × 20 × 40 cm). 5- Coating the walls with emulsion paints. 6- Finishing the walls with gypsum The most important results of the research are that the amount of learning varies from 4.2% to 8.6% in Iraq, and 3.3% to 11.8% in Syria, which considered little compared to the developed countries.
The accumulation of wastes, especially plastic and car tires, has become a major problem facing society today. Therefore, through this research, these wastes were recycled and used to improve some properties of concrete. Recycled crumb rubber from car tires was used instead of sand as a partial replacement of 10%. The substitution was done by two methods: random and equivalent size substitution. As well, 1%polyethylene terephthalate (PET) fiber was added by the volume of concrete to improve some properties of rubberized concrete. Compressive strength, ultrasonic pulse velocity test (UPV) were conducted in this study to investigate the efficiency of PET rubberized concrete, as well the impact resistance test was also conducted to investigated the ability of PET rubberized concrete in term of energy absorption. Slabs of size (50cm×50cm×5cm) were utilized for low velocity impact test. The results indicated there were a reduction in compressive strength and UPV results were observed in PET fiber rubberized concrete the reduction were (37.47% and 5.4%) respectively as compared with PETC mixture and the result of dynamic modulus of elasticity show the same pattern of UPV result , in contrast there was an improvement in the impact resistance when PET fiber and crumb rubber were used it increased by(117.63% and 52.9% ) for random and equivalent replacement respectively as compared with PETC.
This paper presents the experimental results of eight slabs made of Ferrocement. All specimens were )700mm (long, )300mm (wide and )50mm (thick. These specimens were divided into two groups (The first group has four specimens coursed of normal sand gradient and in the other four specimens, the sand that passing from sieve No. 8 was neglected), to investigate behavior of slabs under bending effect and studying the cracks that generated after bending then, comparing the results between these two groups. A thin square welded wire mesh was used as reinforcement. The number of wire mesh layers was varied between 0 to 3 layers. Ultrasonic Pulse Velocity (UPV) Test was used to detect the cracks. The results showed that there was a slight rise in bending for first group slabs compared with second group slabs. Maximum bending strength was achieved for both slab groups with 3 layers of wire mesh. it was shown that there was a significant convergence in the load values required to cause appearing of the first crack and final failure for the two groups. The percentage of ultimate load between slab reinforced with 3 layers and without reinforcement was (25.27%) for the first group, while the increase in ultimate load for a specimen that reinforced with 3 layers was (24.16%) compared to specimen without reinforcement for the same group. On the other hand, the results showed an improvement in the performance of the second group slabs due to its resistance to appearing of cracks resulted from bending. The percentage of increasing cracks after bending for the unreinforced specimen in group 1 was (9%) compared with the unreinforced slab in group 2. Whereas the numbers of cracks number in slab reinforced with 1 and 2 layers in the second group were less than slabs with 1 and 2 layers in the first group about (8.86 %) and (7.77%), respectively. While this percentage for a specimen with 3 layers in group 2 was about (8.62%) less compared to the specimen with 3 layers in group 1..
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.
In recent years, hospital waste has been one of the most serious issues in Iraq and other parts of the world. The current study aims to measure and analyze hospital waste output across all departments at the Ramadi Teaching Hospital. The data on waste generation rates gathered for the study were primarily based on existing records of field management of hospital waste over the course of eight months (one week per month) for all departments in the hospital; however, some random sampling information was provided to supplement the data. The results revealed that the estimated rate of medical waste creation at Ramadi hospital was between 144 and 188 kg/day, whereas the general (non-medical) waste generation was between (240-278) kg/day. In terms of patient numbers and per occupied bed, the average medical waste generation rates were from 0.60 to 0.90 kg/patient/day and (0.85-1.11) kg/bed/day, respectively, whereas the average general trash generation rates ranged from 0.86 to 1.15 kg/patient/day and 1.42-1.64 kg/bed/day. The recent analysis concluded that the hospital's segregation procedure is still inefficient, and there is room for improvement in terms of reducing hazardous medical waste creation
In this study, eight rectangular reinforced concrete beams strengthened by bottom steel plates firmly interconnected to them by headed-stud shear connectors are manufactured using self compacting concrete and tested up to failure under two point loads to demonstrate the effect of steel-plate thicknesses, lengths, and the shear-connector distributions on the behavior, ductility and strength of this type of beams. A trial mix conforming to the EFNARC Constraints had been successfully carried out to satisfy the three fresh tests of SCC, these tests are flowability, passing ability and segregation resistance. The results show that there is a substantial improvement in the flexural resistance, increasing the flexural stiffness and decreasing the ductility ratio due to thickening steel plate, On contrary, increasing the spacing between shear connectors to 50% had slight effect on the flexural resistance, but subsequent increase of their spacing to 100% had seriously lowered that resistance, The spacing between shear connectors has a primary effect on the average flexural stiffness and ductility ratio. In regard to the steel plate length, its shortening has reduced the flexural resistance significantly, decreased the average flexural stiffness and had increased the ductility ratio. The experimentally determined ultimate flexural strength had been compared with its corresponding one computed by the "Strength Method" using ACI requirements where high agreement gained between them due to the nearly perfect interaction provided by SCC. The eight composite beams had also been analyzed by the non-linear three dimensional Finite Element Analysis employing ANSYS program (release 12.1),where high agreement is achieved compared with experimental results.
Traffic movement is considered a compound phenomenon that is impacted by behavioural, economic, and physical aspects. It is performed within the context of an urban system that consists of road networks and crossings, where the movement crouches to depend. The measuring of identifying their size and densities and current problems helps to Improve and development for roads and streets network existing and important is intersections for purposes the accessibility, potentiality of future intersections, and network development towards constructing a composition to raise the quality and the efficient performance of roads and streets. The study was dependent on a traffic survey for intersections, areas of urban intersections, and the road network of Al-Ramadi city, as well as the number of vehicles that generated a large volume of traffic flow. The use of the program (HCS 2010) to detect appropriate for purposes decreasing traffic congestion and delayed trip time in the areas based on existing and future districts that generate different types and purposes of journeys to lessen the delay trip time to lessen traffic congestion. Therefore, research looks at both sides: first, a study of the existing intersections of the main road network and urban streets, including an examination of the components and shapes of these intersections in the study area; second, an examination of the importance placed on these intersections by the planning and design process.
ABSTRACTConstruction industry is becoming an increasingly global business. Competition in theindustry is intensifying, and projects are becoming larger and more complex. Customersare becoming more demanding, and increasingly they are looking for complete packagesof construction services. In this environment, the relationships between suppliers, projectmanagers and customers are the key to success. Customers will need to be confident thatcompanies can get the job done. Companies will need to develop plans, communicate andeffectively fulfill these plans, in order to successfully complete projects.Building quality management system (QMS) based on ISO 9001:2000, require managingcompany as a system of interrelated processes, management should plan these processes,identify how they relate to each other, set goals, measure processes and makeimprovements.The objective of this research is to review the concept, definition, principles, and benefitsof ISO 9001:2000 standard and developing the application of the quality managementsystem for Al-Rasheed State Contracting Construction Company.KEYWORDS: ISO 9001:2000 standard, quality, quality management system, customersatisfaction, continuous improvement
Brick as a construction material can be considered one of the most common materials used for a very long time to construct buildings in iraq. The historic building represents one of the most important figures representing the rich history of iraq, which is built with bricks. Due to the aging of this type of building, a necessary improvement and retrofit need to occur. The paper investigates the ability to use different kinds of materials such as cfrp and srg to enhance the brick columns' structural capacity. From the results and discussions, it can be concluded that these materials are suitable to be used for this purpose with some limitations due to brick capacity itself.
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
Abstract: The presented investigation studies the effect of steel fiber content on the dynamic properties of High Performance Steel Fiber Concrete by using non-destructive testes; Vibration tests (Electrodynamics tests) were used to obtain the dynamic modulus of elasticity, dynamic shear modulus (modulus of rigidity), damping capacity, and dynamic Poisson‘s ratio. The results demonstrated in general an improvement in dynamic properties, which were tested for example, the percentage increasing in compressive strength relative to the reference concrete were 2.5%, 6.6%, 5.8% for High Performance Concrete (HPC) with 0.5%, 1%, and 1.5% steel fiber by volume of concrete respectively.
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 %.
The difficulty that faces the geotechnical engineers how to find the alternative and effective method to improve bearing capacity and reduce foundation settlement. Therefore, the skirt is considered one of the methods to improving the shallow foundation bearing capacity on different soil. The mechanism of skirt work is confinement soil below the foundation and decrease settlement of the foundation. Soil engineers are worked to devise this method as an alternative to pile foundation for conventional buildings. This paper reviews most of these studies of skirted foundations with different types of soil including laboratory tests, field tests, centrifuge models, numerical method and theoretical analysis; these studies are used in investigation the behaviors skirted foundations.
Slurry infiltrated fiber concrete (SIFCON) is a relatively new high performance material and can be considered a special type of fiber concrete (FRC) with high fiber content. The matrix consists of a flowing mortar or cement slurry that must penetrate well through the network of fibers placed in the mold. SIFCON has excellent mechanical properties combined with high ductility and toughness values. SIFCON a relatively new material, is composed of mud (cement or cement and sand), water, a plasticizer (water reducer), and fibers. All previous studies have used waste steel fibers, steel fibers and other fibers, but in this study, plastic fibers were made from polyethylene terephthalate (PET) by cutting carbonated beverage bottles. The main objectives of this study are: Determination the effect of the waste plastic fiber volume ratio on the strength and deformation of (SIFCON) samples under the influence of bending loads. Both flexural strength and toughness properties were determined by testing samples (100×100×400) mm at 28 and 56 days of age. The results obtained from these tests were compared with those performed on conventional tests. Aspect Ratio equal to (36.8) and three volume ratios (3%, 5% and 7%) of the total volume of the concrete mixture were used to add fibers with different volume ratios. A conventional concrete mix was created as a reference for comparison. Bending strength and fresh concrete tests were performed. And compared with the reference mixture and according to the analysis of the results. The results showed an improvement in bending strength .It was found through the flexural examination that the flexural strength of the mixture containing fiber percentage (7%) achieved the highest strength compared to the rest of the ratios used, compared with the reference mixture (Ref.) by (32.25, 27.5)% for ages (28, 56), respectively.
One of the most important aspects of the developing any area is creating a viable road network and defining the relationship between landscape use and road networks. Proper communication and direction are essential to the proper construction of any network. In addition to providing chances for production and consumption, resource extraction, and social cohabitation, the road network also functions as a hub for these activities. As a consequence, this contributes to the development of cities and the improvement of the level of living. However, Ramadi's road network has not received much attention and evaluation. To identify Ramadi road network transportation indicators, the researchers used geospatial information systems. Connectivity was assessed using the alpha, beta, gamma, and eta indices to describe and analyse the network. The data was collected in the first quarter of 2024. The Alpha, the beta, the gamma, and the eta indexes show weak Al-Ramadi road network connections. Indexes are 0.197, 1.26, 0.43, and 0.82. The research indicates a loss in network connectivity in the study region, necessitating the prioritization of new the roads and a city plan to mitigate network shortages.
The gypseous soils are distributed in many locations in Iraq. The Engineering properties of such soil will be changed when it is wetted and it leads to failure which causes danger on the structures built on. This reason needs to study its properties and to find the way to treat it. In this study, natural properties of soil prepared from Samarra-Salah al deen governorate were studied. The gypsum content of soil is about 32%. To improve this soil, many trials were carried out on the soil by additive of Portland cement and calcium chloride. For the importance of the compressibility of the soil, the effect of the additives were studied and it is found that addition of 3% of cement or 5% of calcium chloride will improve the soil compressibility.
This study is conducted to investigate the strength and stiffness of clayey soil stabilized with fly ash-based geopolymer for unpaved roads. Two sodium hydroxide concentrations of 6 and 8M and two alkali solution ratios of NaOH:Na2SiO3= 1 and 1.5 were considered. Other factors such as fly ash replacement ratio (by mass), curing period, and curing temperature were held constant at 15%, 48 hours, and 65 C, respectively. The unconfined compressive strength (UCS) and ultrasonic pulse velocity (UPV) tests were performed to evaluate the mixtures. Outcomes of this study revealed that the strength of the clayey soil could be increased by up to 94%. Additionally, increasing sodium silicate content in the alkali solution increased the solution's activity and yielded higher strength and stiffness. This study confirms the effectiveness of the geopolymer binder for the improvement of soil strength and stiffness.
An experimental investigation was conducted to study the strength, behaviour and deflection characteristics of two way slabs made with both self-consolidating concrete (SCC) and conventional concrete (CC). Six concrete slabs were tested to failure under simply supported uniform by distributed loading conditions. The variables were concrete type and macro synthetic fibres ratio (0%, 0.07% and 0.14%). The performance was evaluated based on crack pattern, ultimate load, load-deflection response and failure mode. The results showed that the ultimate strength of SCC slabs was larger than that of their CC counterparts. The results also showed an improvement of the behaviour and strength of slabs by adding the synthetic fibres.
SIFCON is a relatively new material and consists of slurry (cement or cement and sand), water, super plasticizers (water reducers) and fibers. In all previous research, steel fibers and other types of fibers were used, but in this study, waste plastic fibers Polyethylene Terephthalate (PET) created by cutting carbonated beverage bottles were used for the first time in the production of SIFCON. Three volume ratios (3%, 6% and 10%) of the total volume of the concrete mixture were used to add fibers in different volume ratios, and a reference concrete mixture was created for comparison. Tests of compressive strength, impact resistance, ultrasound transmission velocity check and other tests were performed on the constructed models. Compared with the reference concrete, according to the analysis of the results. The results showed an improvement in the compressive strength it increased by (18.5%), an increase in the impact resistance by (416.67%), and a decrease in the velocity of ultrasound by (19.42%).
The appropriate planning policies for the reconstruction and rehabilitation of devastated towns and cities have a role prominent and important in the activation of spatial development processes where appropriate to give the selected positive results in the reconstruction and improvement of the previous methods in this area. From this point the quest is considering the possibility of choosing planning policy objective and proposed for the reconstruction and rehabilitation of the city of Ramadi to what came to him from the devastation and destruction as a result of the military operations that took place for the period from 2013 -2016 and the belief of the argument (requires the success of the military operations that accompanied the success of the processes of reconstruction being the mutually reinforcing) it was proposed three development policies is the policy of modernization and urban renewal policy and re-new residential neighborhoods and the policy of pairing between the old and new planning, taking into account the future expansion.The study found after using the method of quantitative analysis (method Analytical Hierarchy Process AHP) as a way diagram of the calendar that the third policy is a combination of old and new planning policy taking into account the urbanization of the city is the best among the proposed development policies, and having been using direct questionnaire segment of experts and specialists affairs planning as representing stakeholders and Shan has been used as a way of governing and the officer to know the credibility and reliability in the accuracy of the results of the quantitative hierarchical analysis.