الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In the last decade from the obvious progress in science and technology in all fields was resulted in the availability of new various materials and techniques. As one of the most important industries is concrete industry, which has significant benefit from such progress. In recent years, most interests of researchers describe mechanical properties of special concrete types and design methods of structural members not taking into consideration the economic factor. The aim of the research work is to study the economics of reinforced concrete structures design by using special concrete technology studying its effect on a total cost of design and cost of the concrete elements. To achieve the objective of this research, we studied two stages. The first stage is represented as experimental work program that includes three different type of special concrete with total numbers of 29 mixes which contain G1 shaped from 12 mixes of self-compacting concrete (SCC), G2 contains 8 mixes of high strength concrete (HSC) and G3 shaped from 8 mixes of lightweight concrete (LWC). A series of testing were conducted to select the best mixtures in terms of lower unit weight and cost, and higher compressive strength to compare all mixes with normal weight concrete (NWC) which is the control of the category. The materials used in this study are ordinary Portland cement (CEM I 42.5 N),cement contents of 350, 400, and 450 kg/m3 , at w/c ratio rate 0.32 to 0.4, the amount of water was adjusted according to fine materials content. The silica fume ratio was ranged between 5 to 20% as addition and replacement of cement content, limestone powder ratios were 5 to20 % for SCC and HSC of cement content, while LWC were 5 to 40% of cement content. The superplasticizer dosage varied from 0.5% to 3% of cement content, the fine to coarse aggregate ratio (40 to 60%), maximum size of aggregate (20mm), type aggregates (crashed stone), and foaming agent admixture by percentage between 4% of cement content. The second stage is a case study for three-dimension model of conventional structure multi stories (14 Stories) designed by the help of a design software process (ETABS, CSICOLTM, and SAFETM) according to (ACI-318).xii For assessing the cost effectiveness of NWC, SCC, HSC and LWC on the elements structure cost and construction total costs. Also, cost analysis for one m3 of concrete items, which includes direct cost, indirect cost, margin of profit, and risk allowance. Results indicated that utilizing of HSC achieved more benefits and economic cost in columns by rate 26% cost save compared to NWC. By utilizing LWC in slabs, beams, and HSC in columns lead to decreasing total costs for building by 11% compared to NWC. In addition, self-compacting concrete it can be used with an only additional cost up to 18% in condensed reinforcement in concrete structures. As the results indicated that reinforced steel, was the first factor most important and effect are on the total cost, and by using minimum reinforcement ratio would lead to significant reduction in the total costs. Utilizing minimum contents of cement in the mixture would lead to significant impact on the reduction of cost. Utilizing minimum contents of Superplasticizer in the mixture would lead to significant low cost, in addition, enhancing the properties of both fresh and hardened concrete. Using of contents minimum from high-quality materials do not increase the building costs and that using high-quality materials causes a decrease in the costs demonstrates that it is possible to build a durable building and save money at the same time.