List of Articles بتن معمولی

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  1 - Investigation of the effects of high temperature on compressive and tensile strength and modulus of elasticity of alkali-activated concrete
  Mohammadhossein Mansourghanaei
  10.30495/civil.2022.696525
  In recent years, improving the mechanical properties of alkali- activated concrete with the aim of being superior compared to those of the conventional concrete and reducing environmental hazards caused by the lack of mineral resources and release of toxic carbon dioxid More

  In recent years, improving the mechanical properties of alkali- activated concrete with the aim of being superior compared to those of the conventional concrete and reducing environmental hazards caused by the lack of mineral resources and release of toxic carbon dioxide gas (in cement production process) has been noticed by civil engineering researchers. In this laboratory research, a mixing design of ordinary concrete containing Portland cement with a grade of 500 kg/m3 and a mixing design of alkali-activated concrete based on blast furnace slag were made. In order to check the mechanical properties, tests of compressive strength, tensile strength and modulus of elasticity of concrete were performed under the temperatures of 21 and 600 ℃ at the age of 90 days of curing.  Based on the results, applying high temperature (600 ℃) to concrete samples caused a 42% and 15% drop in compressive strength, a 56% and 21% drop in tensile strength, and a 63% and 49% drop in modulus of elasticity for ordinary and  alkali-activated concretes, respectively.  The compressive strength of alkali-activated concrete was 11% and 64% more than that of the normal concrete at 21 and 600 ℃, respectively. The tensile strength of alkali-activated concrete exhibited a 9% decrease and 63% superiority compared to normal concrete at 21 and 600 ℃, respectively. The elasticity modulus of alkali-activated concrete was 16% and 62% higher than that of the normal concrete at 21 and 600 ℃, respectively. The results of the scanning electron microscope images are in accordance with the other test results of this research. Manuscript profile
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  2 - Evaluation of self-compacting concrete and ordinary concrete, by core method, in deep foundations
  nobakht bakhtyari jamshid esmaili mehdi Amri
  Situ concrete piles, are the most widely used type of deep foundation. In Iran experience shows, that technical problems and economic performance by avoiding the use of ordinary concrete with a slump an extremely high in these types of candles. Poor and low compress res More

  Situ concrete piles, are the most widely used type of deep foundation. In Iran experience shows, that technical problems and economic performance by avoiding the use of ordinary concrete with a slump an extremely high in these types of candles. Poor and low compress resistance, durability and high water permeability in the subsurface environment, the effects of this type of concrete planning. The excellent strength, permeability to ensure proper compaction, concrete ‌ ease and speed up the planning run, the significant advantages of self-compacting concrete. These benefits are especially situ concrete pile planning, most appear to be. In This paper compares core strength situ by taking samples from two typical arrangement of pile ordinary and self-compacting concrete and important results have been obtained. The core samples, to a depth of 14 m in which different levels of ground benchmark are tested show that the use of self-compacting concrete has technical  and economical advantages, and notable administrative lead to greater uniformity in resistance acquisition, located in the upper part of the pile is. This section, the maximum stresses due to vertical and lateral loads. Therefore, the use of self-compacting concrete in deep foundations, can widely replace traditional methods. Manuscript profile