بررسی اثر آب به سیمان و حجم الیاف فولادی در پارامترهای شکست بتن خودمتراکم حاوی الیاف فولادی

نوع مقاله : علمی - پژوهشی

نویسندگان

1 دانشجوی دکتری سازه، دانشکده مهندسی شهید نیکبخت ، دانشگاه سیستان و بلوچستان، زاهدان، ایران

2 استاد، دانشکده مهندسی شهید نیکبخت، دانشگاه سیستان و بلوچستان، زاهدان، ایران

3 دانشیار ، دانشکده مهندسی شهید نیکبخت، دانشگاه سیستان و بلوچستان، زاهدان

چکیده

در این تحقیق اثر نسبت اب به سیمان و درصد حجمی الیاف فولادی بر روی پارامترهای شکست بتن خو متراکم به دو روش کار شکست و اثر اندازه مورد بررسی قرار گرفته است. در یک برنامه ازمایشگاهی نسبت آب به سیمان و درصد حجمی الیاف فولادی متغییر در نظر گرفته شده ، بدین منظور 5 طرح اختلاط در 2 سری ساخته شده است که در سری اول نسبت اب به سیمان متغییر (شامل مقادیر 42/0 ، 52/0 و62/0 )و درصد الیاف فولادی مقدار ثابت 3/0 درصد در نظر گرفته شده و در سری دوم درصد الیاف فولادی متغییر ( شامل 1/0 ، 3/0 و 5/0 درصد )و نسبت اب به سیمان مقدار ثابت 52/0 در نظر گرفته شده است. نتایج نشان می دهد که با افزایش نسبت آب به سیمان انرژی شکست کاهش و بتن تردتر میشود هر چند که در نسبت آب به سیمان کمتر شاهد رفتار متفاوتی می باشیم و همچنین با افزایش درصد الیاف فولادی انرژی شکست افزیش و بتن شکل پذیر تر می گردد، همچنین نتایج نشان می دهد افزایش در صد الیاف فولادی می تواند در کاهش اثر اندازه موثر باشد. انرژی شکست در روش کار شکست نسبت به روش اثر اندازه مقدار بیشتری دارد و نسبت GF/Gf برای تمام طرح اختلاط ها محاسبه شده است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Studying Water to Cement Ratio and Steel Fiber Volume Fraction Effects on the Self-Compacting Steel Fiber-reinforced Concrete Fracture Parameters

نویسندگان [English]

  • mohammad ghasemi 1
  • mohammad reza ghasemi 2
  • Seyed Roohollah Mousavi 3
1 department of civil engineering velayat univercity, iranshahr , iran
2 departemen of civil engineering, university of sistan and balochestan, zahedan, iran
3 Assistant Professor, Dept. of Civil Engineering, Univ. of Sistan and Baluchestan
چکیده [English]

In this research, efforts were made to study the effects of water to cement ratio (W/C) and steel fiber volume fraction (V_f (%)) on the fracture parameters of self-compacting steel fiber-reinforced concrete using both Work Fracture and Size Effect Methods. In an experimental program, a variety of water to cement ratio and volume of steel fibers were considered and five mix designs were prepared in two series. In the first, water to cement ratio were altered (Includes values :W/C=0.42, 0.52, and 0.62) with a constant volume of steel fiber (V_f=0.3%), and in the second, varied volume of steel fibers (Includes values: V_f=0.1, 0.3, and 0.5%) with a constant water to cement ratio (0.52) were considered. Results have shown that an increase in the water to cement ratio reduces the fracture energy, However, we see a different behavior in the lower water to cement ratio, while an increase in the volume of steel fiber not only increases the fracture energy causing the concrete to become more ductile, but it can also reduce the size effect greatly. G_F⁄G_f has been found for all mix designs about 11.81 and it has been concluded that the work fracture method yields more fracture energy than the Size effect method.

کلیدواژه‌ها [English]

  • Fiber reinforced concrete
  • fracture energy
  • Steel Fiber
  • Self-Compacting Concrete
  • size effect
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