ارائه ی روشی جدید جهت تعیین جابجایی و نیروی وارد بر شمع های نصب شده در شیب های خاکی

نویسندگان
1 دانشگاه رازی
2 دانشجو
چکیده
پایداری شیبهای خاکی در اثر عوامل مختلف مانند نیروهای زلزله، تغییر تراز سطح آب زیر زمینی، خاکریزی در بالادست شیب و یا خاکبرداری از پایین دست شیب، تهدید می گردد. با افزایش نیروهای محرک از مقاومت خاک کاسته شده و در نهایت خاک به مرحله تسلیم می رسد. با افزایش نقاط تسلیم، سطح گسیختگی در شیب ایجاد می شود و در نهایت باعث ناپایداری شیب خاکی می گردد. بکی از راهکارهای پایدارسازی شیب های خاکی نصب یک ردیف شمع در دامنه شیب می باشد. در این مقاله تلاش شده است بر مبنای سطح گسیختگی اولیه ی ایجاد شده در شیب و نیروی های جانبی ناشی از وزن گوه گسیختگی و با در نظر گرفتن مشخصات مقاومتی خاک، روشی جدید جهت محاسبه ی نیروی وارد بر شمع ارائه شود. سپس جابجایی سر شمع با استفاده از حل معادلات دیفرانسیلِ مربوطه محاسبه می گردد و در نهایت، نتایج حاصل از روش تحلیلیِ پیشنهاد شده با مقادیر حاصل از روش اجزای محدود مقایسه می شود. در این مقاله دو رابطه ی تحلیلی جدید پیشنهاد شده است که یکی برای محاسبه نیروی وارد بر شمع و دیگری برای محاسبه جابجایی نوک شمع است که در نوع خود کاری جدید و نو است. نتایج حاصل از تحقیق حاضر با نتایج دیگر محققین صحت سنجی شده است که تطابق خوبی با یکدیگر دارند.

کلیدواژه‌ها


عنوان مقاله English

A New Method for Estimating of displacement and Lateral Force Acting on Stabilizing Piles in Earth Slope

نویسنده English

A. Reza Mazaheri 2
2 Ph.D Student
چکیده English

What should be considered at the beginning of any stabilization process besides slope safety is the minimization of expenses. Therefore, excavation on slope upstream and/or filling slope downstream and/or moderating slope angle are the primary and effective stabilization methods. If these methods cannot provide the desirable factor of safety it would be necessary to put effort in other methods such as increasing soil strength parameters, draining surface water and sub-surface (ground) water at embankments, and installing retaining walls and piles. Implementation of these solutions is usually costly and sometimes in order to achieve a desirable factor of safety it is necessary to combine one or several methods. Anyway, the aforementioned solutions are aimed at mitigating the driving force behind ruptures and/or increasing resistive forces. Slopes stabilization methods can be studied as empirical, analytical, and numerical methods. This classification has been so far used by researchers and has undergone numerous studies. One of the methods used for improving resistive forces is the installation of piles in earth slopes. Installing piles for stabilizing susceptible earth slope is an effective way of preventing the imbalance of force and instability. Stabilizing effect by using pile is provided by the passive resistance of the pile below the slip surface and load transfer from the sliding mass to the underlying stationary soil or rock formation through the piles due to soil arching mechanism. Moreover, slope stability and optimizing pile location by installing a row of piles have been studied by many researchers. The piles are embedded in the stable soil by the length 5D (D=pile diameter), because the zone of influence of each pile has been demonstrated not to exceed 5D and the length of the pile is restricted to 10D. In this paper a new method is presented for estimating of displacement and lateral force acting on stabilizing piles in earth slopes. The growth mechanism of lateral force acting on stabilizing piles in a row due to the surrounding ground undergoing plastic deformation is discussed, and its theoretical analysis is carried out considering the interval between the piles (Ito and Matsui, 1975). Several methods have been proposed to determine the force exerted on the pile in addition to having the merits, defects such as lack of accuracy required in a particular interval between the piles. In this paper with regarded to initial slip surface and acting force due to weight of failed soil is proposed lateral force acting on piles. 1. The assumptions are considered in this paper are, 2. The suitable location for installing of piles is middle of slope. 3. The pile behavior is considered as elastic. 4. The soil behavior is considered as elastoplastic. 5. The pile tip is embedded in the stable soil by the length 5D.

کلیدواژه‌ها English

Earth Slope
Lateral force on pile
Pile displacement
Stabilization
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