مقایسه مقاومت تک محوره مدل عددی و آزمایشگاهی توده‌سنگ درزه‌دار

نوع مقاله: مقاله پژوهشی

نویسندگان

دانشگاه تهران

چکیده

ارزیابی مقاومت توده سنگ در انتخاب محل مناسب، طراحی و اجرای موفق پروژه­های معدنی و عمرانی از ملزومات اولیه است. مقاومت فشاری سنگ بکر می­تواند به کمک آزمون­های استاندارد آزمایشگاهی تعیین شود، درحالی‌که تعیین این پارامتر برای توده سنگ به‌شدت درزه‌دار خیلی مشکل است. تخمین سریع این خصوصیت جهت ارزیابی اولیه، به‌طور قابل‌ملاحظه‌ای هزینه آزمایش‌های صحرایی را کاهش می دهد. آزمون­های آزمایشگاهی زیادی به وسیله محققین مختلف بر روی توده سنگ درزه­دار با ترکیب درزه­های متفاوت برای تعیین مقاومت فشاری تک محوری انجام شده است. در این تحقیق، مدل­های آزمایشگاهی، به کمک روش المان مجزا در حالت سه بعدی به کمک نرم‌افزار 3DECمدل‌سازی گردیده و تغییرات مقاومت حداکثر نسبت به تغییرات شیب درزه ها و گام یا قفل‌شدگی موردبررسی قرار گرفته است و نتایج حاصل از مدل‌سازی سه‌بعدی با نتایج آزمایشگاهی و نتایج حاصل از مدل‌سازی دو بعدی (نرم‌افزار UDEC) مورد مقایسه قرار گرفت است و ملاحظه شد که نتایج مدل‌سازی سه بعدی اختلاف کمتری نسبت به مدل‌سازی دو بعدی از نتایج آزمایشگاهی را نشان می‌دهند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Comparison Study between Numerical and Physical Modelling of UCS of Jointed Rock Mass

نویسندگان [English]

  • M Asadizadeh
  • R Rahmannejad
چکیده [English]

An accurate assessment of strength of jointed rock masses is one of the most important requirements in the site selection, design and successful execution of mining engineering and geotechnical projects. The strength of intact rock can be determined through standardized laboratory tests, although this is very difficult for heavily jointed rock masses. A quick estimation of these properties for preliminary evaluation of alternate sites will considerably reduce field tests costs. A large number of laboratory tests on a jointed rock mass with various joint configurations had been done by many researchers in order to determine the strength of jointed rock under uniaxial loading. In this present paper, an attempt has been made to compare the results between numerical simulation of experimental modeling on strength and deformability of jointed block masses. For this purpose, numerical simulation of experimental tests for rock mass modulus and strength has been done by 3 Dimensional Distinct Element Code (3DEC). Results showed that numerical simulation and experimental testes have a good agreement and numerical simulation can be used in order to estimate deformation modulus of rock mass.

کلیدواژه‌ها [English]

  • Numerical simulation
  • Uniaxial Compression Test
  • Jointed rock mass
  • Strength
  • 3DEC
  • UDEC
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