بررسی امکان وقوع شکست هیدرولیکی در هسته سدهای خاکی با معیارهای مبتنی بر فشار بحرانی

نوع مقاله : علمی - پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد مهندسی عمران. دانشکده فنی و مهندسی. دانشگاه خوارزمی. تهران. ایران

2 استادیار، گروه عمران، دانشکده فنی و مهندسی، دانشگاه خوارزمی، ایران، تهران

چکیده

یکی از مهم ترین خطرهایی که سدهای خاکی را تهدید می کند، شکست هیدرولیکی است. این پدیده اغلب در زمان اولین آبگیری سد، زمانی که فشار آب بطور ناگهانی افزایش می یابد، رخ می دهد. برای مطالعه ترک هیدرولیکی در هسته سد راههای مختلفی وجود دارد. در این مقاله به بررسی پدیده شکست هیدرولیکی در سد حاجیلر چای تبریز پرداخته شده است. برای این منظور ابتدا با استفاده از مجموعه Geo-Studio که برنامه ای مبتنی بر المان محدود می باشد به بررسی پدیده شکست هیدرولیکی در دو مقطع وسط هسته و وجه بالادست هسته سد برای دو نوع خاک رس با پلاستیسیته کم و زیاد پرداخته و نواحی مستعد این پدیده شناسایی شده است. در مدلسازی ها ساخت لایه به لایه سد نیز در نظر گرفته شده و وزن لایه ها در محاسبه تنش ها و تغییر شکل ها لحاظ گردیده است. در نتیجه این ارزیابی ها خاک رس با پلاستیسیته زیاد به عنوان خاک منتخب و خاک رس با پلاستیسیته کم به عنوان خاک بحرانی برای استفاده در هسته سد انتخاب گردیدند. همچنین معیارهای فوکوشیما و قنبری به ترتیب خوشبینانه ترین داده ها و محافظه کارانه ترین داده ها را دارا بوده و احتمال وقوع شکست هیدرولیکی در بخش هایی از هسته سد محتمل تشخیص داده شد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigating the possibility of hydraulic fracture in the core of earth dams with criteria based on critical pressure

نویسندگان [English]

  • mostafa zalnejad 1
  • seyed shahab Emamzadeh 2
1 MSc Student , Civil Engineering Department. Kharazmi University, Tehran,, Iran
2 Assistant Professor, Civil Engineering Department,. Kharazmi University, Tehran, Iran
چکیده [English]

One of the most important hazards that threaten earth dams is hydraulic failure. This phenomenon often occurs during the first flooding of the dam, when the water pressure rises suddenly. There are several ways to study hydraulic fracture and damage in a dam core. In this paper, the phenomenon of hydraulic fracture and seepage in Hajilerchai dam body in Tabriz has been investigated. For this purpose, first, using Geo-Studio, which is a program based on finite element, investigates the phenomenon of hydraulic failure in the two middle sections of the core and the upstream side of the dam core for two types of clay with low and high plasticity. The phenomenon has been identified. In modeling, layer-by-layer construction of the dam is also considered and the weight of the layers is taken into account in calculating stresses and deformations. As a result of these evaluations, high plasticity clay was selected as the selected soil and low plasticity clay was selected as the critical soil for use in the dam core. Also, Fukushima criteria and Ghanbari criteria had the most optimistic and conservative data, respectively, and the possibility of hydraulic failure in parts of the dam core was identified as possible.

کلیدواژه‌ها [English]

  • Hydraulic failure
  • hydraulic cracking
  • earthen dam
  • Hajilerchai dam
  • Geo - Studio Software
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