بررسی آزمایشگاهی تأثیر نحوه قرارگیری ژئوتکستایل در ظرفیت باربری پی روی خاک مسلح

نوع مقاله : پژوهشی اصیل (کامل)

نویسندگان
احد اوریا
الیار حیدرلی
دانشگاه محقق اردبیلی
چکیده
در این تحقیق، اثر نحوه قرارگیری ژئوتکستایل در زیر پی در ظرفیت باربری آن بصورت آزمایشگاهی مورد بررسی قرار گرفته است. در این آزمایش‌ها، خاک زیر پی در یک جعبه فولادی به ابعاد 30×25×90 سانتی­متر و پی نواری بصورت یک ورق فولادی به ابعاد 2×5/7×25 سانتی­متر شبیه‌سازی شده­است. تأثیر قرارگیری مسلح­کننده‌ها در ظرفیت باربری پی با نه چینش مختلف بصورت تک لایه، دو لایه و سه لایه بصورت پیوسته و غیر‌پیوسته در بعد سوم، مورد بررسی قرار گرفته است. نتایج این تحقیق نشان می‌دهد استفاده از مسلح­کننده‌ها بصورت نوارهای منقطع که به‌صورت مناسبی در فضای سه‌بعدی توزیع شده باشند، باعث افزایش بازده تسلیح می‌گردد. در تسلیح چند لایه، استفاده از نوارهای گسسته مسلح‌­کننده‌ها به‌گونه‌ای که نواری واقع در اعماق لایه‌های مجاور زیر یکدیگر قرار نگیرند، باعث افزایش چشمگیر بازده تسلیح خواهد شد.

کلیدواژه‌ها

موضوعات

عنوان مقاله English

Laboratory Investigation of the Effect of the Geotextile Placement Pattern on the Bearing Capacity of Footing on Reinforced Sand

نویسندگان English

Ahad Ouria
Eliar Heidarly
University of Mohegan Ardabili
چکیده English

This paper presents the results of an experimental study on the effect of the pattern of reinforcement placement in reinforced soil on the bearing capacity of a strip foundation. A steel box filled with sand with the dimensions of 100×25×30 cm (Length, widths, and height) was used as the test base. The strip footing was simulated by a steel plate with dimensions of 25×7.5×2 cm. The sand used in this study was a poorly graded sand (SP) according to the unified soil classification system. A woven type geotextile was used as reinforcement. The effect of the reinforcement’s placement pattern on the bearing capacity of the foundation was investigated with nine different layouts including single, double, and three-layered reinforcement layouts. All the specimens prepared with a similar initial unit weight and void ratio. The tests conducted using a displacement-controlled loading device. The loading was applied with a rate of 1 mm/second. All the tests repeated at least three times to assure the accuracy and the repeatability of the results. The results of these tests indicated that the bearing capacity of the foundation increases as the length of the reinforcement increases but up to a certain limit and then remains constant. Although increasing the number of reinforcements layer increased the bearing capacity of the foundation, however, the effectiveness of the geotextile in the improvement of the bearing capacity decreased. Placement of the reinforcements in a discrete pattern improves the effectiveness of the reinforcement on the bearing capacity improvement. In multi-layer reinforcement layouts, using discrete strips of reinforcements in each elevation without overlapping with upper- and lower-layers of reinforcements, resulted the maximum efficiency of reinforcements influence in the improvement of the bearing capacity of the foundation. In the recent case, for a specific cross-sectional area of the reinforcement, the bearing capacity of the foundation could be increased by 20% using 17% less reinforcement. The results of this study indicate that the layout of the reinforcement pattern is a very important factor in the bearing capacity of foundations on reinforced soil. With a proper placement of reinforcements, the maximum bearing capacity of the foundation could be achieved with a minimum amount of reinforcement material.

کلیدواژه‌ها English

Reinforced soil
Geotextile
bearing capacity
Reinforcement Layout
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مهندسی عمران مدرس
دوره 21، شماره 3
خرداد و تیر 1400
صفحه 21-34