اثر اندازه نمونه بر مقاومت فشاری، کششی و خمشی بتن‌های حاوی الیاف فولادی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشیار، مرکز تحقیقات ژئوتکنیک لرزه‌ای و بتن توانمند، گروه مهندسی عمران، واحد سمنان، دانشگاه آزاد اسلامی، سمنان، ایران

2 1- کارشناس ارشد مهندسی سازه، گروه مهندسی عمران، واحد سمنان، دانشگاه آزاد اسلامی، سمنان، ایران

چکیده

استفاده از الیاف در بتن سبب کاهش قابل‌توجه تردی و شکنندگی بتن شده و بتن حاصله از همگنی بالایی برخوردار خواهد بود. از آنجایی که برای تعیین خصوصیات مکانیکی بتن از نمونه‌گیری‌های مختلفی در سراسر دنیا استفاده می‌شود، در این تحقیق 160 نمونه بتن الیافی شامل 64 نمونه مکعبی برای آزمایش مقاومت فشاری، 64 نمونه استوانه‌ای برای آزمایشات مقاومت فشاری و کششی و 32 نمونه تیر برای آزمایش مقاومت خمشی مورد آزمایش و بررسی قرار گرفتند. همچنین در این پژوهش 4 رده‌ی بتن مورد آزمایش قرار گرفتند که از هر رده بتن و هر ابعاد 4 نمونه ساخته شد که 1 نمونه بدون الیاف (به عنوان نمونه مبنا) و 3 نمونه با الیاف فولادی دو انتها قلاب (5/0درصد حجم بتن مصرفی) بود. نتایج نشان داد که مقاومت خمشی، کششی و فشاری بتن با حضور الیاف افزایش یافته و ضرایب تبدیل مقاومت جدیدی برای نمونه‌های حاوی الیاف ارائه گردید.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

The Effect of Specimen Size on Compressive, Tensile and Flexural Strength of Steel Fiber Reinforced Concrete

نویسندگان [English]

  • Alireza Mortezaei 1
  • Arman Ebrahimian 2
1 Associate Professor, Seismic Geotechnical and High Performance Concrete Research Centre, Civil Engineering Department, Semnan Branch, Islamic Azad University, Semnan, Iran
2 M.Sc.، Civil Engineering Department, Semnan Branch, Islamic Azad University, Semnan, Irann
چکیده [English]

Nowadays, concrete is known as one of the most used building materials in the world. Being economical, the availability of constituents, good resistance under the fire and atmospheric factors, the ability to fit in shapes and molds, and also the high compressive strength are factors that have made public acceptance in the use of concrete as a building material. The use of fiber in concrete has increased dramatically over the last few decades. The use of fiber in concrete causes the concrete to become flexible to a considerable extent and the resulting concrete is highly homogeneous. Since the concrete specimens are used worldwide to determine the mechanical properties of concrete, in this study, 160 samples of fiber concrete containing 64 cube samples with dimensions of 5×5×5, 10×10×10, 15×15×15, 20×20×20 cm for testing of compressive strength, 64 cylindrical cylinders with dimensions (diameter × height) of 15 × 30 and 10 × 20 cm for compressive strength and tensile strength tests and 32 samples of beam with dimensions of 10×45×10 and 15×60 ×15 were used for flexural strength testing. Furthermore, in this study, 4 concrete ranges of 20MPa, 25MPa, 30MPa and 35MPa were tested. Of each concrete grade and each dimension, four samples were made; one of which was non-fibrous (as the base sample) and three samples with fibers. The steel fibers used were two-end hooks of 3.5 cm in length and 0.8 mm in thickness, with 0.5% of the volume of concrete used. The results showed that the flexural strength, tensile and compression strength of the concrete increased with the presence of fibers and some new conversion factors were proposed for the fiber-containing specimens.

کلیدواژه‌ها [English]

  • size effect
  • Steel Fiber
  • Compression strength
  • tensile strength
  • Flexural Strength
  • conversion factor

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