بررسی تاثیر تغییرات ژئوسل بر پایداری شیروانی در خاک غیراشباع

نوع مقاله: مقاله پژوهشی

نویسندگان

1 گروه مهندسی عمران، واحد نجف‌آباد، دانشگاه آزاد اسلامی، نجف‌آباد، ایران.

2 گروه مهندسی عمران، دانشگاه صنعتی اصفهان، ایران.

3 گروه آب و محیط‌زیست، مجتمع عالی آموزشی و پژوهشی صنعت آب و برق اصفهان، وزارت نیرو، اصفهان، ایران.

10.22091/cer.2019.4270.1147

چکیده

این پژوهش به بررسی عملکرد و بازدهی مسلح‌کننده ژئوسل در پایداری شیروانی مسلح شده با لایه ژئوسل در شرایط خاک غیراشباع می‌پردازد. شیروانی مسلح شده با ژئوسل به دلیل اینکه مسلح‌کننده ژئوسل دارای ارتفاع (سه بعدی) بوده، همانند یک تیر در خاک عمل می‌کند و به‌دلیل داشتن خصوصیات خمشی، دارای ممان اینرسی و در نتیجه مقاومت خمشی نیز می‌باشد. این امر، سبب کاهش جابه‌جایی شیروانی و افزایش ضریب اطمینان شیروانی خواهد شد. در نظر گرفتن شرایط غیراشباع برای خاک، کمک زیادی در ایجاد نتایج نزدیک به واقعیت می‌کند. یکی از مدل‌های شناخته شده در میان مدل‌های الاستوپلاستیک برای مدل‌سازی خاک‌های غیراشباع، مدل بنیادی بارسلون می‌باشد که این مدل به نرم‌افزار FLAC2D توسط کدنویسی اضافه شده است. در این مطالعه، به بررسی تغییرات ضخامت، طول و تعداد لایه ژئوسل بر پایداری شیروانی پرداخته شده است. نتایج به‌دست آمده نشان می‌دهد که بازده مسلح‌کننده ژئوسل در افزایش ضریب اطمینان به تعداد لایه و عمق قرارگیری آن بستگی دارد. با افزایش عمق قرارگیری اولین لایه ژئوسل نسبت به ارتفاع شیروانی، مقدار جابه‌جایی جانبی و قائم خاک در قسمت بالای شیروانی افزایش خواهد یافت. همچنین ظرفیت باربری با افزایش طول لایه ژئوسل افزایش می‌یابد. با افزایش طول لایه ژئوسل، مقاومت سطح مشترک، مقاومت کششی بسیج شده و ممان خمشی افزایش می‌یابد.همچنین با افزایش ضخامت ژئوسل مقدار ممان اینرسی افزایش یافته و در نتیجه، مقدار لنگر خمشی مسلح‌کننده ژئوسل افزایش پیدا می‌کند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigating the Effect of Geocell Changes on Slope Stability in Unsaturated Soil

نویسندگان [English]

  • Behnam Mehdipour 1
  • Bahram Nadi 1
  • Hamid Hashemalhosseini 2
  • Masoud Mirmohammadsadeghi 3
1 Department of Civil Engi-neering, Najafabad Branch, Islamic Azad University, Najafabad, Iran.
2 Civil Engineering Group, Is-fahan university of technol-ogy, Isfahan, Iran
3 Departeman of water and natural Environment, Isfahan Higher Education and Re-search Institute (IHEARI); Mimistry of Energy, Isfahan, Iran
چکیده [English]

The purpose of this research is to investigate the performance and efficiency of reinforced slope in the stability of geocell layers in unsaturated soil conditions. Slope reinforced with geocell, due to the fact that the geocell has a height (three-dimensional), acts as a beam in the soil, and because of its flexural properties, it has a moment of inertia as well as bending strength, which reduces the displacement and increases the coefficient reliability of the slope. Considering unsaturated conditions of soil contributes a lot to make results close to reality. One of the well-known models among elastoplastic mod-els for modeling unsaturated soils is Barcelona's basic model, which has been added to the FLAC2D software by codification. Changes in thickness, length, and the number of geocell layers are remarkably effective on slope stability. The results show that the geocell's reinforcing efficiency depends on the number of layers and the depth of its placement. As the depth of the geocell's first layer increases, the lateral and vertical side elevation of the upper part of the slope increases with respect to the elevation. Load capacity increases with increasing geocell length. By increasing the length of the geocell lay-er, the joint strength, the tensile strength of the mobilized, and the bending moment are increased. Also, by increasing the thickness of the geocell, the amount of moment of the inertia increases, and as a result, the amount of geocell reinforcement bending moment increases.

کلیدواژه‌ها [English]

  • Keywords: Barcelona Basic Model
  • FLAC2D
  • Geocell
  • Slope
  • unsaturated soil
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