بررسی مکانیک شکست سنگ‌های مختلف

نوع مقاله : مقاله پژوهشی

نویسنده

نویسنده مسئول و استاد یار، دانشگاه صنعتی اصفهان، دانشکده مهندسی معدن

چکیده

مکانیک شکست، بررسی فرآیند رشد ترک در یک حوزه معین تنش است. میزان مقاومت ماده در برابر پیشرفت ترک، چقرمگی شکست نامیده می‌شود. در این تحقیق، نمونه‌های مختلف آزمایشگاهی ترک‌دار برای تعیین چقرمگی1 سنگهای مختلف استفاده شد. از آنجائیکه انجمن بین المللی مکانیک سنگ2 بر اساس دو نوع آزمایش استوار است (میله کوتاه3، آزمایش خمش سه نقطه‌ای4) در اینجا آزمایش خمش سه نقطه‌ای انتخاب شده است و در این آزمایشها دو حالت مطرح است:
1- هدایت بار5
2- هدایت جابه جایی6، که برای دو نوع سنگ مختلف هدایت بار5 انتخاب شد.

کلیدواژه‌ها


عنوان مقاله [English]

Fracture Mechanics of Different Rocks

نویسنده [English]

  • Masoud Cheraghi Seifabad
چکیده [English]

Fracture mechanics approach is to assess the process of crack propagation in a known stress field. The amount of material strength against the crack propagation is named fracture toughness. In this research, different cracked samples are used to determine the fracture toughness of different rocks. The methods proposed by ISRM (International Society for Rock Mechanics) are two tests; i.e. three point  bend test and short rod. The present research is based on the three point bent test. Also, in these tests two levels are utilized, 1-load control 2-displacement control, but in the present tests the level I is chosen for two types of rocks.

کلیدواژه‌ها [English]

  • Fracture mechanics
  • Fracture Toughness
  • Three Point Bend Test
  • Anisotropy
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