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Concrete properties are dependent on many parameters such as ingredients, production and technology, construction methods and curing conditions that have made concrete as a complex and unpredictable material. But these are virtually ignorable against its precious advantageous and precise studies on above parameters may help us to produce concretes with our desirable properties. Ingredients are of those important parameters that play an essential role. Therefore it is seriously important to have enough knowledge about ingredients, their combined effects and interactions and also effects of their properties on concrete properties. Pozzolan materials can help us to achieve desirable characteristics of concrete and develop its mechanical and physical parameters, hence they are used widely. Improvement of mechanical parameters, permeability reduction, and durability increase are among their fabulous benefits of application. They are deemed as essential ingredients of high durable and strength concretes. Pozzolan weighted ratio is major parameters which develop a homogenous and united medium and improve the physical and mechanical parameters of concrete. The effects of pozzolan on physical and mechanical properties of concrete, moreover it’s specifications, depend on the parameters of other ingredients, such as type of aggregates, particle size distribution of aggregates, fineness modulus of fine aggregates, water-cement ratio, cement type and ect. Then study of combined effects of pozzolan specifications and parameters of other ingredients is inevitable for achieving to a concrete with ideal parameters. As we know, microsilica is the most popular pozzolan material which is used widely and it’s parameters and other ingredients parameters (such as type of aggregates, particle size distribution of aggregates, fineness modulus of fine aggregates, water-cement ratio, cement type and ect) have combined effects on the variation of concrete physical and mechanical parameters. So, in this study we selected microsilica as a pozzolan to determine the combined effects of its weighted ratio content, fineness modulus of fine aggregates and water-cement ratio on physical and mechanical properties of concrete. In this study, the combined effects of microsilica weighted ratio content, fineness modulus and water-cement ratio on physical and mechanical properties of concrete were investigated. For determination the effects of microsilica weighted ratio content on concrete parameters in different water-cement ratios and particle size distributions, 5 different microsilica weighted ratio contents, 3 water-cement ratios and 3 particle size distributions, were selected and totally 45 mix designs were prepared and subjected to slump test and compressive strength, tensile strength and modulus of elasticity tests. Obtained results show a direct relationship between microsilica weighted ratio content and physical and mechanical properties of concrete. Increase in microsilica content from 0% to 10 % in all water-cement ratios and fineness modulus, leads to slump decrease and mechanical parameters increase, while from 10 % to 20 % of microsilica content, mechanical properties fall down, but the reduction trend of slump continues. Also it can be seen that the effect of different weighted of microsilica, on physical and mechanical properties of concrete, reduces by increasing in water-cement ratio and intensifies with increment of fineness modulus of fine aggregates.

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The most important aims in Concrete-1404 are compressive strength more than 50 Mpa, quality and durability. These items seems to ignore before that in Iran. The high strength concrete production always needs to use suitable materials, attention to mix design, optimizing cement percentage and other component in concrete. For reaching to a trustable mix designs and aspects of high strength concrete, it needs to be evaluated by a complete investigation which can provide all three aspects of strength, workability and durability of a 1404-concrete. In this paper, cubic concrete samples are made in a way which is affected by 5 variables. These 5 Effective ranges are included: 1) Three different types of coarse and fine aggregate gradation curves which are made of finnest through roughest grading of aggregates according to ASTM C33. 2) Three types of high water reducers used in exact same mix design to compare the effects of these 3 different kind of superplasticizers on high strength concrete. These three type are grade F with polycarboxilate-ether based, grade F with sodium naphthalene solphonate based and grade G as a super high water reducer admixture. 3) Effects micro silica with 5, 7 and 12 percentage of total cement amount are added to compare the results on high strength concrete. 360 and 410 kg cement per m3 are used in source concrete mixtures as the regular using amount in practical projects in Iran. 4) The effect of cement content, with fixed w/c and 5% micro silica, which are between 375 through 425 kg/m3. And 5) the effects of adding filler which are thoroughly investigated on mechanical properties, durability and economy plan. There are 20 mix design in 6 groups are prepared with total cementitious materials from 360 to 425 kg/m3. To compare the results, in these experiments the water cement ratio has been fixed to 0.25. The tests used in experiments were compressive strength test by 3000 KN hydraulic compressor and 24 hours water absorption test. The mechanical and durability properties are recognized by these tests. For evaluating fresh concrete properties, slump test was done. Economical aspect is studied and compared by comparing price of materials and content that are used in each mixture. The results show that the variables were impressively affected the compressive strength in high strength concrete. Using optimum conditions of the studied mixture design can improve the mechanical properties of concrete. By optimizing components in mixture design, high strength concrete can be made even with cement content of 400 kg per cubic meter. The 360 and 410 kg cement with adding 5% micro silica showed the best improving in compressive strength. Enhancing cement more than 400 kg results to decrease compressive strength. High water reducers with polycarboxilate ether based show better results in mechanical and fresh concrete properties and also in economical aspect. Adding filler to mixture led to decrease compressive strength and increase durability, however it had no effects on economical properties of high strength concrete. It can be concluded that aggregate grading can still lead to changes in compressive strength, durability and workability of HSC.

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Today, most of the existing pavements in the country are asphalt pavements. This is due to the abundance of oil in the country and the lack of a suitable alternative for it. Asphalt pavements, despite their popularity and ease of implementation, also have disadvantages.  The low service life of asphalt pavements and the exorbitant costs that are paid for their maintenance, as well as the damages caused in some special areas of the pavement, such as airport runways, require the use of pavements that can have many characteristics. It is better than asphalt paving to meet the needs of these areas. In recent years, the use of concrete pavement compared to asphalt pavement has had a higher economic justification. Also, in some cases, the use of concrete pavement, such as airport runways, which must have high resistance to pressure, impact, and wear, is the only viable option. But concrete pavement also has disadvantages such as low durability against freezing and thawing cycles in cold regions. Therefore, it is necessary to take into account the necessary measures to increase the durability of concrete, compensate for the disadvantages of concrete pavements against destructive factors and increase their service life to a significant amount, so that it is economically justified compared to asphalt procedures. The indigenous concrete mixing plan is a new approach that has been considered as an economic solution for the sustainable development of many civil infrastructures in the world. For this purpose, in this article, a practical and effective method to increase the efficiency and life of concrete pavements of Mashhad Airport by using potential mineral resources and also to minimize maintenance costs has been introduced. In this study, 8 concrete mixing plans were prepared with aggregates from two local quarries, Mehrizi and Rezaei, in relation to Mashhad airport, and then the mechanical properties and durability behavior of all mixtures were carried out to provide the optimal local mixing plan. The results showed that by adding polypropylene fibers to the samples containing microsilica, the bending strength of the concrete samples increased up to 8.7 MPa. Based on the results, concrete samples containing Mehrizi aggregates showed better performance in terms of mechanical behavior and durability compared to concretes made from Rezai mine aggregates. Also, among the mixtures of Mehrizi mine, the mixing design containing polypropylene fibers and 7% replacement of microsilica with cement showed far higher resistance and durability than other samples. In such a way that the rate of improvement in compressive strength, resistance to chlorine ion invasion, melting and ice phenomenon and silica alkali reactions compared to the control sample after the end of each of the aforementioned tests is 22.81%, 418%, 400% respectively. % and 189.31%. Therefore, based on the mentioned results, a local mixing plan using Mahden Mehrizi materials is suggested for use in the apron of Mashhad airport.