Sustainable buildings reflect the interest rising of Urbanism sectors in issues of economic development, optimal utilization of natural resources and greater reliance on "renewable" sources of energy. The objective of the research is to identify and Diagnosis the priority of alternatives to sustainable projects with the of relative importance and to review the value engineering indicators in building and the possibility of applying sustainable building standards such as British Standards (BREEAM), US Standards (LEED), Pearl Rating System and Green Pyramid Assessment System. The research is based on four axes. The first axis is the foundations of architectural design to serve the optimum use of the available resources. The second axis is based on the methods of producing building materials with optimum use of natural resources; Third axis: The sustainable use of the building to achieve conservation of the environment using economical sources of energy, waste recycling and maintenance of the building according to the required specifications. The fourth axis, which means Using renewable energies to provide the building with the energy it needs. The literature and researches in the field of research work were reviewed, which included the concept of applying value engineering method in the sustainable buildings and the most important areas of their applications during the stages of completion of the project and what are the basic considerations that should be provided in the construction projects, Which represents the practical aspect in relation to the various stages of the field study, which includes aspects related to the field survey, through the preparation and Configure of questionnaires derived from the theoretical study and interviews and also focused on the indicators and areas of applications during the stages of the project (pre-construction stage, implementation stage, A maintenance and operation, post-construction phase (end of the age of the building) and what are the basic considerations that must be provided in the construction projects. The research provided this results: The Sustainable Buildings Projects location Selection Index is The most important indicators of value engineering for sustainable buildings where relative importance of it is 72%, according to the respondents' answers, conversely the architectural index, with its relative importance of 55%, while the electromechanical index was 68% and the constructional index by 65%. And the development of a waste management program during the process of construction and operation so that this program achieves the minimum recycling and the use of new alternatives to building materials drawing on what has been developed within other areas in the development of the construction industry.
Recycling the old paving waste and reusing it in the construction of new highways was resorted to, and this is a good step from an economic point of view, as well as from an environmental and health point of view, as it reduces carbon emissions and eliminates a large amount of disposable reclaimed asphalt pavement materials (RAP). This study aims to evaluate the best layer of pavement structure; base, binder, and surface layers for inclusion (RAP) materials based on stability and indirect tensile strength. In addition, highlight the best percentage that can be added from RAP to achieve positive results and better than that associated reference mixture in terms of Marshall test and Indirect tensile strength test RAP materials collected from different sources Karbala and Fallujah, were adopted in this study at percentages of 20%, 30%, and 40% by weight of the asphalt mixture. Two scenarios of incorporating RAP materials have been adopted : The first is considered that RAP as a black rock in which the effect of aged binder surrounding the aggregate of RAP is neglected while the second is not considered RAP as black rock and the influence of aged binder in RAP materials has been taken into consideration. Dora bitumen has been adopted in the current study which is used commonly in Iraq. It has been highlighted that the best layer in which RAP can be incorporated is the base layer, with a percentage up to 40% that RAP without considering RAP black rocks regardless of the sources of RAP
This paper presents and discuses some properties of self-compacting concrete SCC containing optimum contents of different types of cement replacement materials CRMs like fly ah, silica fume and limestone powder. The purpose is to evaluate the performance of SCC mixtures to choose the best one for strengthening purposes of corroded reinforcement concrete beams. In a preliminary work, the theoretical optimum contents of the above materials were specified using statistical program (Minitab) and they were verified experimentally. This verification based on checking fresh properties such as slump flow, T500, L-box and segregation resistance as well as compressive strength. The optimum contents of CRMs: 14% fly ash, 19% limestone, 18% silica fume plus fly ash and 11% silica fume were selected and studied. Compressive, tensile, and flexural strengths were examined, as well as the modulus of elasticity, water absorption and porosity (which reflect the related durability properties) were examined. Test results show that the optimum verified theoretical percentage of a combination of fly ash and silica fume, at 18% by weight of cement with a fixed water-binder ratio of 0.33 showed the best overall performance. It was deduced that this SCC mix gave the highest mechanical properties and the lowest porosity and water absorption. For example, the compressive strength increased by 36.25% as compared to SCC mix containing limestone powder. Further, the porosity and water absorption decreased by 120.8% and 164% respectively as compared to the above same SCC mix. Thus, it could be used for strengthening purpose of corroded RC beams.
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.
Determining building materials and their types and determining their effect on concrete properties are consistent with the technical and design variables of buildings. From this point of view, the research came to include theoretical studies and empirical tests for some materials, focusing on the aggregate as a basic material involved in the formation of concrete. The first part includes the introduction, research problem, assumptions, importance, and purpose of the research. the second part was to conduct practical experiments by designing different concrete mixtures in the mixing ratios and the type of aggregate until results were reached regarding the resistance of the concrete that was produced as a result of the difference in densities between ordinary aggregate concrete and lightweight aggregate concrete. Through that, for example, the lightweight aggregate with an age of (7) days and a mixing ratio of (1: 2: 4) gave strength to the models used (19.58) Mpa, and for the same mixing ratio and at an age of (28) days, it gave durability ( 22.83) Mpa. When the mixing ratio was changed to (1: 1.5: 3), it was (25.74) MPa and (32.34) MPa at the age of (7) days and (28) days, respectively. These results give an accurate indication that the aggregate is light in weight with similarity to the ordinary aggregate in obtaining concrete with a bearing strength within the approved specifications without guaranteeing the environmental treatments and the resulting loads
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
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.
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.
The problem of discarded tires has received a lot of attention from many authors. Incorporation of rubber aggregate recycled from waste tires is one of the solutions to this issue. This research is based on evaluating fresh and hardened properties such as slump flow, T500, segregation resistance, and L-box tests, compressive strength, impact resistance, and flexural toughness. Rubber aggregate replacements in the self-compact concrete mixes was 10% by volume of fine aggregate. Additionally, both PET and steel fibers are utilized at a volume rate of 0.25%.The outcomes indicate that introducing rubber declines rheological and hardened properties, whereas incorporating hybrid fibers enhances hardened properties such as compressive strength, impact energy, and flexural toughness. The best increase impact energy was obtained at roughly 166.6% when 0.25% hybrid fibers and 10% rubber were used. 74.21 was the greatest increase in flexural toughness when 0.25% hybrid fibers (SCCH3) were used. As for the compressive strength, it was the highest by about 11%.
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 aims to propose a new methodology of obtaining the basic solution of the transportation model, which is one of the operations research. Transportation model aimed to find the economic solution to the plan of allocation of products from production centers to consumption centers. One of the important issues of application the transportation model is the issue of transfer raw materials for construction projects (such as ready-mix concrete) and for which there is usually a set of options for production centers as there is always a group of consumption centers (construction sites). This application was chosen because of the wide use of it and due to its impacts on macroeconomic level. Started by reviewing the current methods of obtaining the basic solution of the transportation model, then the factors that are not taken into account in these methods have been identified and, accordingly, two methods have been developed to obtain the basic solution of the transportation model. The first method depends on the indicator of the biggest costs of transport between the centers, while the second method uses the cost multiplied by the amount transmitted (actual cost) as an indicator to determine the basic solution of the transportation model. Unlike other methods, this method considers all variables mentioned in the objective function. Finally, the proposal method has been illustrated by the use of an empirical example.
A voided slab is an innovative type of reinforced concrete slab system developed recently, that has proven its excellence in terms of its structural, environmental, and economic benefits. The self-weight of a slab can be considerably reduced using different shapes of void formers like spherical, cubical, and donut. All researchers confirm that the self-weight of the slab decreases by up to 40%. Various researchers have carried out experimental and numerical studies for studying one-way flexural strength and punching shear strength of voided reinforced concrete slabs. However, the one-way or two-way flexural strength of the voided slab still needs to be acutely investigated. This paper deals with the survey on many titles of selected high impacted journals to illustrated almost criteria of investigations of these types of slabs. The main outcomes of this paper are the term environmental protection, sustainable and plastic waste reduction had a role not a little in this research, as 16% of the research on this topic were studied. Also, the plastic material governs the subject of the raw materials used to make the voids;43% of researches used this material.