ظرفیت باربری پی‌ها در موقعیت‌های مختلف نسبت به زمین شیب‌دار

نوع مقاله : پژوهشی

نویسنده

• مریم حق بین

دانشگاه ازاد واحد اسلامشهر

10.22067/civil.v29i2.45069

چکیده

هدف از طراحی پی انتقال بار سازه به خاک زیرین بدون ایجاد گسیختگی برشی و نشست اضافی در خاک می‌باشد. بنابراین انتخاب ظرفیت باربری مناسب نکتۀ مهمی است که در هر پروژه باید بررسی شود. در شرایط خاص پی‌ها در موقعیت‌های مختلف نسبت به زمین شیب‌دار (روی شیب، بالای شیب، پایین شیب) قرار می‌گیرند و موقعیت شیب زمین بر ظرفیت باربری پی تأثیر می‌گذارد. درواقع شیب زمین بر سطح گسیختگی ایجادشده در خاک زیر پی تأثیر قابل توجه می‌گذارد و در نتیجه توجه به موقعیت پی نسبت به زمین شیب‌دار برای تعیین ظرفیت باربری دقیق پی ضروری است. در مقالۀ حاضر، روش تحلیلی دیوار حائل مجازی براساس پایداری خاک زیر پی ارائه شده‌است. هم‌چنین، تأثیر موقعیت‌های مختلف پی نسبت به شیب زمین، فاصلۀ پی نسبت به زمین شیب‌دار و عمق و عرض پی بر ظرفیت باربری پی بررسی شده‌است. نتایج نشان می‌دهد که در شرایط مختلف پی، به‌ترتیب ظرفیت باربری پی واقع بر زمین هموار و بالای شیب و پایین شیب و واقع بر شیب بزرگ‌تر می‌باشد. از قابلیت‌های رابطۀ ارائه‌شده تعیین تأثیر زاویۀ شیب و مسلح‌کنندۀ زمین شیب‌دار بر ظرفیت باربری می‌باشد. ازجمله نتایج تحقیق این است که فاصلۀ مؤثر پی از شیب که بیشتر از آن تأثیر شیب بر ظرفیت باربری از بین می‌رود، 5/4 برابر عرض پی است. در نهایت، نتایج به‌دست‌آمده با نتایج تحلیلی، آزمایشگاهی و عددی ارائه‌شده توسط دیگر محققان مقایسه شد و هم‌خوانی قابل قبولی را نشان داد.

کلیدواژه‌ها

• ظرفیت باربری پی، زمین شیب‌دار
• ضریب لرزه‌ای
• فاصلۀ پی
• عمق و عرض پی

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عنوان مقاله [English]

Bearing Capacity of Strip Footings in various Locations with Respect to Sloping Ground

نویسنده [English]

• maryam haghbin

azad university of Islamshahr

چکیده [English]

The purpose of footing design is transferring structure load to soil without causing shear failure and extra settlement in soil. Therefore, footing bearing capacity should be considered in various projects. In special case, footings are placed in various positions with respect to slope ground and position of ground slope affects footing bearing capacity. In fact, slope affects failure surface of soil beneath the foundation remarkably and therefore, footing location with respect to slope must be cared to determine exact footing bearing capacity. In present paper, analytical method is presented based on soil stability beneath the footing. Virtual retaining wall method is used in present study and by applying equilibrium between active and passive forces on virtual wall, footing bearing capacity on reinforced and unreinforced soils is determined in various positions with respect to slope ground. Also, varied parameters include soil resistance, footing spacing with respect to slope ground, width and depth of foundation and seismic coefficient. Results indicate, in various depths and widths of foundation, bearing capacity of footing on flat ground is more than top of slope and bearing capacity of footing top of slope is more than down of slope. Also, bearing capacity of footing on slope is minimum. Based on proposed method, footing location with respect to slope affects passive and active force on virtual retaining wall and footing bearing capacity remarkably. Also, the proposed method can determine effect of slope angle and reinforcement on footing bearing capacity. Presented method indicates effective distance from slope crest is almost 4.5B. Finally, the predicted results are compared with those reported from analytical and experimental methods performed by others, indicating an acceptable agreement.

کلیدواژه‌ها [English]

• Footing Bearing Capacity
• Slope Ground, Seismic Coefficient
• Footing Spacing, Depth and Width of Footing

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