مطالعه آزمایشگاهی تاثیر شکل و ابعاد نمونه و نوع سیمان مصرفی بر روی ضرایب تبدیل مقاومت فشاری نمونه های بتنی

نوع مقاله : یادداشت پژوهشی

نویسندگان

1 استادیار گروه سازه، دانشگاه صنعتی قم

2 استادیار دانشکده فنی و مهندسی، گروه مهندسی عمران، دانشگاه آزاد اسلامی واحد تهران غرب، تهران، ایران

چکیده

آزمایش مقاومت فشاری بتن یکی از مهمترین آزمایش ها برای کنترل کیفیت بتن در سازه های عمرانی محسوب شده و بر اساس شرایط کارگاهی و ضوابط آیین نامه ها و استاندارهای مرتبط، قالب‌هایی با اشکال و ابعاد مختلف (مکعبی و استوانه ای) برای تهیه نمونه های آزمایشی مورد استفاده قرار می گیرند. هدف از انجام این تحقیق بررسی و تعیین تغییرات ضرایب تبدیل مقاومت نمونه ها با اشکال و ابعاد مختلف به یکدیگر برای بتن های رده C35 و C45 ساخته شده با انواع مختلف سیمان می باشد. در این تحقیق برای ساخت نمونه ها از سیمان های نوع 425-1، 2 و 5 استفاده شده و تعداد 162 نمونه مکعبی و استوانه ای شکل با ابعاد و اندازه های (200×200×200) میلیمتر، (150×150×150) میلیمتر و (300×150) میلیمتر در سنین 3، 7 و 28 روز مورد آزمایش مقاومت فشاری قرار گرفته است. نتایج حاصل از این تحقیق نشان می دهد که علاوه بر شکل و اندازه نمونه ها، نوع سیمان مصرفی نیز بر روی مقاومت و ضرایب تبدیل مقاومت نمونه ها با اشکال و اندازه های مختلف تاثیر گذار است. همچنین نتایج حاصل نشان می دهد که اختلاف ضرایب تبدیل مقاومت بدست آمده با ضرایب تبدیل متناظر ارائه شده توسط مبحث نهم مقررات ملی ساختمان در سنین 3 و 7 روزه نمونه ها حداکثر و در سن 28 روزه حداقل می باشد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental study on the influence of the shape and size specimen and the type of cement used on the conversion factors of compressive strength of concrete specimens

نویسندگان [English]

  • Baitollah Badarloo 1
  • mahboobeh pirizadeh 2
1 Assistant professor in structural Eng., Department of Civil Engineering, Qom University of Technology (QUT), Qom, Iran
2 Assistant Professor, Department of Civil engineering , College of Engineering, West Tehran Branch, Islamic Azad University, Tehran, Iran
چکیده [English]

Compressive strength test of concrete is one of the most important tests for controlling the quality of concrete in construction structures and, moulds with different shapes and dimensions (cubic and cylindrical) are used to provide experimental specimens based on the workshop conditions and the regulations of the relevant codes and standards. The purpose of this research is to investigate and determine changes in the conversion factors for the strength of specimens with different shapes and dimensions for C35 and C45 concretes made with different types of cement. In this research, 425-1, 2, and 5 cements were used for the preparation of specimens. A total of 162 cubic and cylindrical specimens with dimensions (200 × 200 × 200) mm, (150 × 150 × 150) mm and (150x300) mm at the age of 3, 7 and 28 days have been tested for compressive strength. The results of this study show that in addition to the shape and size of the samples, the type of cement used also affects the strength and conversion factors for the strength of the specimens with various shapes and sizes. The results also show that the difference in conversion factor for strength obtained with the corresponding conversion factors provided by the Iranian National Building Code, Part 9 at the age of 3 and 7 days of the specimens is maximum and is minimum at the age of 28 days.

کلیدواژه‌ها [English]

  • compressive strength of concrete
  • conversion factor
  • cubic specimen
  • cylindrical specimen
  • cement
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