ارائه یک روش طراحی برای دیواره‏های میخ‏گذاری‏شده و مقایسه آن با روش طراحی سنتی

نوع مقاله : مقاله پژوهشی

نویسنده

• محمد حاذقیان

دانشکده مهندسی عمران، دانشگاه یزد، یزد

10.22067/jfcei.2022.76614.1142

چکیده

در روش طراحی سنتی برای دیوارهای میخ‏گذاری‏شده که مبتنی بر راهنمای FHWA است، معمولاً مشخصات طراحی میخ‏ها (طول، فاصله و قطر میخ‏ها) در عمق گود ثابت فرض می‏شود. اما در روش طراحی معرفی‏شده در مطالعه حاضر (روش طراحی پیشنهادی) با کنترل گام‏به‏گام ضریب اطمینان برای هریک از ردیف‏های میخ از بالا به پایین گود، مشخصات طراحی آنها در عمق تغییر داده می‏شود. در مطالعه حاضر، ابتدا فرضیات مدل‏سازی بیان و سپس روش مدل‏سازی عددی با آزمون پروژه کلوتره صحت‏سنجی می‏شود. در ادامه جزئیات روش‏های طراحی سنتی و پیشنهادی توصیف می‏شود. سپس یک مطالعه پارامتری برای مقایسه روش‏های طراحی سنتی و پیشنهادی انجام می‏شود. در این مطالعه پارامتری، اثر عمق گود، تراکم خاک، چسبندگی خاک، سربار و ضریب اطمینان پایداری موردنیاز بررسی می‏شود. نتایج مطالعه حاضر نشان می‏دهد که روش طراحی پیشنهادی نسبت‌به سنتی، چگالی حجمی میخ‏ها (مجموع حجم میخ‏ها تقسیم بر مساحت دیواره) را به‌طور متوسط 30% کاهش می‏دهد که از لحاظ اقتصادی قابل توجه است. هم‌چنین نتایج مطالعه حاضر نشان می‏دهد که تغییرشکل تاج دیواره گود در روش طراحی پیشنهادی نسبت‌به سنتی به‌طور متوسط حدود 10% بیشتر است.

کلیدواژه‌ها

• گود
• میخ&rlm
• گذاری
• روش طراحی سنتی
• روش طراحی پیشنهادی
• چگالی حجمی میخ&rlm
• ها

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عنوان مقاله [English]

Proposal of a design method for soil-nailed walls and compare it with the conventional design method

نویسنده [English]

• Mohammad Hazeghian

Department of Civil Engineering, Yazd University, Yazd, Iran

چکیده [English]

In the conventional design method for soil-nailed walls that is based on the FHWA guidance, the nails properties (the length, spacing and diameter of nails) through the excavation depth is usually assumed constant. However, in the design method introduced in the present study (the proposed design method), the nails properties are varied through the excavation depth by step-by-step control of the factor of safety for each row of nails. In the present study, first numerical assumptions are explained and then the numerical modelling methodology is verified through the Clouterre project. Afterwards, the details of the conventional and proposed design methods are described. Next, a parametric study is performed to compare the conventional and proposed design methods. In the parametric study, the effects of the excavation depth, soil density, soil cohesion, surcharge and required factor of safety are investigated. The results of the present study show that the proposed design method compared with the conventional one would decrease on average 30% the nails volumetric density (i.e. the volume of nails divided by the wall area), which is considerable from the economical point of view. Moreover, the results show that the total displacement at the wall crest for the proposed design method is comparatively 10% higher than that of the conventional design method.

کلیدواژه‌ها [English]

• Excavation
• soil nailing
• Conventional design method
• Proposed design method
• Nails volumetric density

مراجع

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