تاثیر خروج از مرکزیت بارگذاری بر ظرفیت باربری پی نواری در مجاورت شیروانی

نوع مقاله : مقاله کامل پژوهشی

نویسندگان

1 گروه مهندسی عمران، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران

2 گروه مهندسی عمران، واحد تبریز، دانشگاه آزاد اسلامی، تبریز

3 گروه مهندسی عمران، واحد شوشتر، دانشگاه آزاد اسلامی، شوشتر

10.22034/ceej.2024.59588.2306

چکیده

مهندسان اغلب هنگام طراحی فونداسیون‌هایی که در مجاورت شیب ها قرار دارند با چالش‌هایی مواجه می‌شوند که تاثیر خروج از مرکزیت با حضور لایه‌های ضعیف به پیچیدگی موضوع می‌افزاید. در تحقیق حاضر با استفاده از آزمون‌های مدل فیزیکی مقیاس کوچک، تأثیر بارگذاری خارج از مرکز بر ظرفیت باربری پی نواری در مجاورت شیروانی با لایه خاک ضعیف مورد بررسی قرار گرفته است. لایه‌های نازک اثرات قابل توجهی بر ظرفیت باربری نهایی دارند، علیرغم اینکه به نظر ناچیز هستند. مجموعه‌ای از آزمایش‌های مدل فیزیکی بر روی یک پی نواری صلب که بر روی بستر چند لایه ماسه ای که در مجاورت شیب قرار گرفته است، انجام شد. اثرات تغییر فاصله پی از تاج شیب و شیب لایه نازک بر روی رفتار پی مورد بررسی قرار گرفت. مشخص شده است که لایه نازک ضعیف ظرفیت باربری نهایی را کاهش می‌دهد. نتایج آزمایشگاهی نشان می‌دهد که مقدار خروج از مرکزیت بر روی ظرفیت باربری نهایی پی تأثیر می‌گذارد و با دور شدن پی از لایه ضعیف و تاج شیب، ظرفیت باربری افزایش می‌یابد همچنین وجود لایه نازک ضعیف در بستر خاکی منجر به کاهش ظرفیت باربری نهایی تا 43 درصد می‌شود.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

The effect of eccentricity of loading on the bearing capacity of strip foundations in the nearest soil slope

نویسندگان [English]

  • Majid Kianpour 1
  • Ahad Bagherzadeh Khalkhali 1
  • Rouzbeh Dabiri 2
  • Mehdi Mahdavi Adeli 3
1 Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
2 Technical and Engineering Faculty, Tabriz Branch, Islamic Azad University, Tabriz, Iran
3 Faculty of Engineering, Shoushtar Branch, Islamic Azad University, Shushtar, Iran
چکیده [English]

Engineers often face challenges when designing foundations that are located on top of or adjacent to slopes. The effect of eccentricity with the presence of weak layers adds to the complexity of the issue. In this research, using small-scale model tests, the effect of off-center loading on the bearing capacity of the strip foundation adjacent to the sloping multi-layer gable with a weak soil layer has been investigated. Thin layers have significant effects on the ultimate load-bearing capacity, despite their seeming insignificance. A series of laboratory model tests were conducted on a rigid strip footing placed on surfaces with different layered slope footings. The test program considered different foundation configurations by varying the distance of the footing from the crest of the slope and the slope of the thin layer. It is found that the weak thin layer reduces the ultimate bearing capacity. The laboratory results show that the amount of eccentricity affects the final bearing capacity of the foundation and increases the bearing capacity by moving away from the weak layer and the crest of the slope. The weak thin layer at the critical distance D = 0 leads to a further reduction of the final bearing capacity by 43%.

کلیدواژه‌ها [English]

  • Weak layer
  • soil slope
  • ultimate bearing capacity
  • eccentricity
  • physical model
  • numerical model

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نشریه مهندسی عمران و محیط زیست
دوره 54، شماره 117 - شماره پیاپی 117
زمستان 1403
اسفند 1403
صفحه 107-119

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