List of Articles بتن بازیافتی

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  1 - Investigating the Effects of Using Microsilica and Nanosilica on the Hardened Mechanical Properties and Durability of SCC Containing Recycled Aggregates
  Reza Farokhzad mohsen mehrpoya
       Today, the wastes remaining from concrete degradation is considered as an environmental problem and is one of the biggest challenges in the building industry. Accordingly, many researchers have decided to re-use the materials of aggregates from More

       Today, the wastes remaining from concrete degradation is considered as an environmental problem and is one of the biggest challenges in the building industry. Accordingly, many researchers have decided to re-use the materials of aggregates from degradation in concrete production cycles. In this paper, attempts were made to assess and if possible to promote the mechanical and durability characteristics after the addition of nano-silica and micro-silica to self-compacting concrete containing recycled aggregates (obtained from worn concrete degradation). One of the points to be considered in this paper was the attempt to use tests such as half-pole testing and concrete wave velocity. In this regard, 72 mixture designs were studied in 8 collections. In these mixture designs, with respect to the content of recycled aggregates, the nano- and micro-contents were changed. Then, the samples underwent mechanical tests including compressive strength and tensile strength, and durability tests including corrosion potential, concrete wave velocity (ultrasonic) and electrical strength. After the tests, with an increase in the use of nano-silica and micro-silica, the efficiency and fluidity of the fresh concrete were reduced, and compressive strength and tensile strength were increased. Also, at fixed strength, nano-silica caused less efficiency and fluidity than micro-silica and also, with an increase in the content of recycled aggregates in concrete, efficiency and fluidity as well as compressive strength and tensile strength of concrete were reduced. Manuscript profile
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  2 - Comparison of the effect of silica fume and fly ash on the mechanical properties of masonry recycled concretes
  Mostafa Azhdarizadeh Seyyed Fathollah Sajedi Mohammad Sirous Pakbaz
  10.30495/civil.2023.701859
  The present study is devoted to the study of the effect of replacing silica-fume (SF) and fly ash (FA) pozzolans on the mechanical properties of recycled concrete (RC) made from recycled masonry coarse aggregates (RMCA).  In manufactured concretes, natural aggregat More

  The present study is devoted to the study of the effect of replacing silica-fume (SF) and fly ash (FA) pozzolans on the mechanical properties of recycled concrete (RC) made from recycled masonry coarse aggregates (RMCA).  In manufactured concretes, natural aggregates were replaced by RMCA at different percentages. In order to improve the mechanical properties of these concretes, different percentages of SF and FA were substituted for part of the cement. Slump and specific gravity tests were performed on fresh concrete and compressive strength, splitting tensile strength, modulus of elasticity, and ultrasonic pulse velocity tests were performed on the hardened concrete. The results indicate that replacement of SF and FA increased the slump and decreased the specific weight of the concretes. Also, the results revealed that replacing 5% and 10% SF improved some mechanical properties of recycled concrete containing 50% of RMCA. Replacement of 15% SF, in concrete containing 25% of RMCA resulted in the close mechanical properties of RC compared with CC without pozzolans. Also, the test results demonstrated that replacing different percentages of Fly Ash, could not improve the mechanical properties of RC. Manuscript profile