بررسی لرزه‌ای ظرفیت باربری پی نواری در مجاورت شیب‌های مسلح شده با ژئوگرید با استفاده از روش تحلیل حدی المان محدود

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار گروه عمران، دانشکده عمران و معماری، دانشگاه ملایر، ملایر، ایران

2 استادیار گروه عمران، دانشکده عمران و معماری، دانشگاه ملایر، ملایر، ایران.

3 کارشناس ارشد مهندسی عمران-ژئوتکنیک، دانشکده عمران و معماری، دانشگاه ملایر، ملایر، ایران.

چکیده

ساخت و ساز در زمین‌های شیبدار، علیرغم محدودیت‌های زیاد، اجتناب‌ناپذیر است. از طرف دیگر به دلیل لرزه‌خیز بودن ایران، بررسی ظرفیت باربری لرزه‌ای پی‌ها دارای اهمیت دوچندانی است. ساخت و ساز در مجاورت شیب با کاهش ظرفیت باربری نسبت به زمین مسطح همراه است لذا استفاده از روش‌های بهسازی از جمله استفاده از مسلح‌کننده‌ها همچون ژئوگرید می‌تواند تا حدی کاهش ظرفیت باربری را جبران نماید. در این تحقیق با استفاده از قضیه کران بالا و پایین روش تحلیل حدی المان محدود و به کمک نرم افزار OptumG2 به بررسی اثر شیب زمین (با زوایای 10 و 20 درجه) بر ظرفیت باربری خاک‌های دانه‌ای با زوایای اصطکاک داخلی مختلف (25، 30، 35، 40 و 45 درجه) در دو حالت لرزه‌ای و استاتیکی پرداخته شد. نتایج نشان می‌دهد با اعمال بار لرزه‌ای با ضریب زلزله افقی 1/0kh=، ظرفیت باربری لرزه‌ای پی بین 2 تا 12 درصد کاهش پیدا می‌کند. همچنین طول موثر ژئوگرید به زاویه اصطکاک داخلی خاک وابسته بوده و بین B2 تا B3 (B عرض پی) تغییر می‌کند. همچنین یافت شد که فاصله ایمن پی از لبه شیب (X/B) به زاویه اصطکاک داخلی وابسته بوده و اثر آن به مراتب از اثر زاویه شیب بیشتر است. در تحلیل حاضر برای زوایای اصطکاک داخلی 25، 30 و 35 این مقدار بین B2 تا B4 و برای زوایای اصطکاک داخلی 40 و 45 درجه حداقل B5 برآورد گردید.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Evaluating the Seismic Bearing Capacity of Strip Foundation Adjacent to Geogrid-Reinforced Slopes Using Finite Element Limit Analysis Method

نویسندگان [English]

  • Mohammad Ahmadi 1
  • Ali Reza Bagherieh 2
  • Fatemeh Mohammadipour 3
1 Assistant Professor, Department of Civil Engineering, Faculty of Civil Engineering and Architecture, Malayer University, Malayer, Iran.
2 Assistant Professor, Department of Civil Engineering, Faculty of Civil Engineering and Architecture, Malayer University, Malayer, Iran.
3 M.Sc. in Geotechnical Engineering, Department of Civil Engineering, Faculty of Civil Engineering and Architecture, Malayer University, Malayer, Iran.
چکیده [English]

Building construction on slopes is inevitable, despite many limitations. Due to the seismicity of Iran, calculating the seismic bearing capacity of foundations is more important. The construction along a slope has been observed to result in a reduction in the bearing capacity. To mitigate this decrease, various improvement techniques, such as soil reinforcements like geogrids, can be employed to partially offset this reduction. The present study investigates the impact of ground slope (10 and 20 degrees) on the bearing capacity of granular soils with varying internal friction angles (25, 30, 35, 40, and 45 degrees) in both seismic and static conditions. This investigation employs the finite element limit analysis method and OptumG2 software to determine the upper and lower bounds of the bearing capacity. The findings indicate that the implementation of kh=0.1 leads to a reduction in the seismic bearing capacity of the foundation, ranging from 2 to 12 percent. The effective length of the geogrid is contingent upon the internal friction angle of the soil and varies within the range of 2B to 3B. Additionally, the study revealed that the optimal distance between the footing and the slope edge (X/B) is influenced by the internal friction angle, with a significantly bigger impact than the slope angle. The optimal distance (X) was estimated to lie within 2B to 4B for internal friction angles of 25, 30, and 35 degrees. Conversely, for internal friction angles of 40 and 45 degrees, the X value was assessed to be no less than 5B.

کلیدواژه‌ها [English]

  • Seismic Bearing Capacity
  • Strip Foundation
  • Slope
  • Geogrid
  • Finite Element Limit Analysis Method

مراجع

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