بهینه‌یابی میزان مصرف الیاف ماکرو سینتتیک درهم تنیده برای بهبود ویژگی‌های مکانیکی بتن

نوع مقاله : علمی - پژوهشی

نویسندگان

1 استادیار، گروه مهندسی عمران، واحد ارومیه، دانشگاه آزاد اسلامی، ارومیه، ایران

2 دانشجوی دکتری گروه مهندسی عمران ، واحد ارومیه ، دانشگاه آزاداسلامی ، ارومیه ، ایران

چکیده

بهبود ویژگی‌های مکانیکی بتن به کمک الیاف یکی از روش‌های رایج فراوری بتن در نظر گرفته می‌شود. افزودن الیاف به بتن باعث افزایش میزان جذب انرژی بتن و شکل‌پذیری بتن می‌شود و از گسترش ترک‌ها جلوگیری می‌کند. الیاف فولادی، پلی پروپیلن و شیشه‌ای از پرکاربردترین الیاف مورد استفاده می‌باشند. علاوه بر آن‌ها، گونه‌های نوینی از الیاف ماکرو سینتتیک نیز معرفی شده‌اند. در این پژوهش، به‌منظور بهبود ویژگی‌های مکانیکی بتن از گونه‌ی نوینی از الیاف ماکرو سینتیتیک بهره‌جویی شده است. نمونه‌های مسلح به 2، 4، 6 و 8 درصد از الیاف به کمک آزمون‌های مختلف فشاری، خمشی، آزمون کششی و هم‌چنین آزمون تعیین ضریب کشسانی مورد ارزیابی قرار گرفتند و میزان مصرف بهینه‌ی آن‌ها انتخاب شد. در این پژوهش سعی بر آن بوده است که شرایط آزمایش تا حد امکان منطبق بر شرایط صنعت باشد تا نتایج نهایی پژوهش قرابت مناسبی با وضعیت کنونی صنعت بتن داشته و قابلیت استفاده داشته باشند. مقایسه‌ی نتیجه‌های آزمون‌ها نشان دادند که بر طبق انتظار، بتن‌های مسلح به الیاف نسبت به بتن‌های معمولی مقاومت فشاری، خمشی، کششی و ضریب کشسانی بیشتری دارند. علاوه بر آن‌، بین درصدهای مختلف الیاف در بتن، در نمونه‌های دارای درصدهای بیشتر از 2درصد، نرخ افزایش مقاومت‌های مختلف نسبت به حالت بدون الیاف کم‌تر است. بنابراین، با توجه به هزینه‌ی الیاف ماکرو سینتتیک، مناسب‌ترین درصد برای مسلح کردن بتن با آن‌ها 2 درصد معرفی شد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Optimizing the Consumption of Intertwined Macro Synthetic Fibers to Improve the Mechanical Properties of Concrete

نویسندگان [English]

  • Ashkan KhodaBandehLou 1
  • Amin Asadi Zeynali 2
1 Assistant Professor of the Faculty of Engineering, Civil Engineering Department, Urmia Branch, Islamic Azad University, Urmia, Iran
2 Ph.D. Student Of Civil Engineering-Structure, Faculty Of Engineering, Civil Engineering Department, Urmia Branch, Islamic Azad University, Urmia, Iran
چکیده [English]

Improving the mechanical properties of concrete with the help of fibers is considered as one of the common methods of concrete processing. Addition of fibers to concrete increases the energy absorption and ductility of concrete and prevents the spread of cracks. Steel, polypropylene and glass fibers are the most widely used fibers. In addition, new types of macro-synthetic fibers have been introduced. In this research, in order to improve the mechanical properties of concrete, a new type of macro-synthetic fibers has been used. Samples reinforced with 2, 4, 6 and 8% of fibers were evaluated using various compressive, flexural, tensile tests as well as elastic coefficient determination tests and their optimal consumption was selected. In this research, it has been tried that the test conditions are as compatible as possible with the industry conditions so that the final results of the research are in good agreement with the current situation of the concrete industry and can be used. Comparison of test results showed that, as expected, fiber-reinforced concretes have higher compressive, flexural, tensile strength and tensile strength than conventional concretes. In addition, between different percentages of fibers in concrete, in samples with percentages greater than 2%, the rate of increase of different strengths is lower than in the case without fibers. Therefore, considering the cost of macro synthetic fibers, the most suitable percentage for reinforcing concrete with them was introduced as 2%.

کلیدواژه‌ها [English]

  • Macro synthetic fibers
  • Intertwined
  • Mechanical properties
  • Optimum percentage
  • Mixing design
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