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تاثیر اندازه و نوع الیاف بر خصوصیات رئولوژیکی و مکانیکی بتن خود تراکم اجرا شده در لایه های مجزا | ||
| علوم و فنون سازندگی | ||
| دوره 6، شماره 1 - شماره پیاپی 18، مرداد 1404، صفحه 1-20 اصل مقاله (846.14 K) | ||
| نوع مقاله: مقاله پژوهشی | ||
| نویسنده | ||
| بهراد عبدالله زاده* | ||
| هلدینگ تخصصی نیرو-موسسه پایاب نیرو | ||
| تاریخ دریافت: 14 مرداد 1402، تاریخ پذیرش: 26 شهریور 1404 | ||
| چکیده | ||
| در بتن ریزی های با حجم بالای بتن در برخی مواقع در لایه های با فاصله زمانی زیاد اجتناب ناپذیر می باشد. بررسی های پیشین نشان داده است که این موضوع میتواندسبب عدم یکپارچگی مکانیکی در لایه های بتن ریخته شده با فاصله زمانی زیاد شود. از این رو خواص مکانیکی و نفوذ ناپذیری بتن های ریخته شده در لایه های متعاقب تحت تاثیر درز ایجاد شده قرار می گیرد.استفاده از الیاف در بتن های خود متراکم مزایا و معایبی در پی دارد.همچنین استفاده از الیاف میتواند خصوصیات رئولوژیکی و مکانیکی بتن خود متراکم اجرا شده در لایه های مجزا را تحت تاثیر قرار دهد.در تحقیق حاضر از دو نوع الیاف شیشه ای و فولادی در ترکیبات جداگانه و دوتایی در ساخت مخلوط های بتنی خود متراکم ریخته شده در لایه های مجزا استفاده شده و نتایج مقاومت های برشی مستقیم، برشی مورب و کشش تحت شکافت بعد از گذشت زمانهای صفر ، 40 ، 80 ، 120 و 160 دقیقه مورد تحلیل قرار گرفته است. درصد ترکیب هریک از الیاف ها در مخلوطهای بتنی بر اساس 0.5، 1و 1.5 وزن سیمان بوده است. آزمایشات 28 روزه برش مستقیم، برش مورب و کشش تحت شکافت بر روی نمونه های مکعبی 15×15×15 صورت گرفته است.نتایج حاصله حاکی آن از است که در بهینه ترین حالت ، استفاده از الیاف فولاد و شیشه باعث افزایش 35 %مقاومت برشی مورب و 20 %مقاومت برشی مستقیم شده است.همچنین استفاده از الیاف فولاد و شیشه باعث افزایش 18% مقاومت کششی تحت شکافت شده است. | ||
| کلیدواژه‌ها | ||
| بتن خود متراکم؛ الیاف فولاد؛ الیاف شیشه؛ مقاومت برشی مورب؛ مقاومت برشی مستقیم | ||
| عنوان مقاله [English] | ||
| Effect of Fiber Size and Type on Rheological and Mechanical Properties of Self-Consolidating Concrete cast in Distinct layers | ||
| نویسندگان [English] | ||
| Behrad abdollahzadeh | ||
| Niro Specialized Holding - Payab Niro Institute | ||
| چکیده [English] | ||
| In concreting with a high volume of concrete, sometimes it is unavoidable in layers with long time intervals. Previous studies have shown that this issue can cause the lack of mechanical integrity in concrete layers poured with a long time interval. Therefore, the mechanical properties and impermeability of concrete poured in subsequent layers are affected by the created seam. The use of fibers in self-compacting concrete has advantages and disadvantages. Also, the use of fibers can improve the rheological and mechanical properties of concrete. affect the self-compacting effect in separate layers. In the current research, two types of glass and steel fibers were used in separate and double combinations in the construction of self-compacting concrete mixtures poured in separate layers and the shear strength results Straight, diagonal shear and tension under splitting after zero, 40, 80, 120 and 160 minutes have been analyzed.The composition percentage of each of the fibers in concrete mixtures was based on 0.5, 1 and 1.5 weight of cement. 28-day tests of direct cutting, diagonal cutting and tension under splitting have been conducted on 15x15x15 cubic samples. The results indicate that in the most optimal case, the use of steel and glass fibers increases the shear strength by 35%. Diagonal and 20% shear resistance has been straightened. Also, the use of steel and glass fibers has increased the tensile strength under splitting by 18% | ||
| کلیدواژه‌ها [English] | ||
| Self-compacting concrete, steel fibers, glass fibers, diagonal shear strength, direct shear strength | ||
| مراجع | ||
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آمار تعداد مشاهده مقاله: 3 |
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