ارزیابی شاخص‌های شکنندگی سنگ‌ها، برای تخمین مدول چقرمگی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشیار گروه زمین شناسی دانشگاه همدان

2 دانشجوی دکتری زمین شناسی مهندسی، دانشکده علوم، دانشگاه بوعلی سینا همدان

3 استادیار، دانشکده فنی و مهندسی، دانشگاه تربیت مدرس تهران

4 دکتری زمین شناسی مهندسی، دانشکده علوم، دانشگاه فردوسی مشهد

چکیده

شکنندگی و مدول چقرمگی سنگ‌ها از جمله خصوصیات ذاتی آن‌هاست که نقش تعیین کننده‌ای در عملیات حفاری سنگ‌ها دارند. در این پژوهش خواص مکانیکی سنگ‌های گرانیت، گرانودیوریت، دولومیت، هورنفلس و مرمر در محدوده پروژه تونل انتقال آب گلاس در حاشیه شهرستان نقده مطالعه شده است. با بهره‌گیری از سطح زیر منحنی تنش-کرنش و هم‌چنین خواص مقاومتی سنگ‌های مذکور، 13 شاخص شکنندگی و مدول چقرمگی محاسبه شده است. روابط آماری بین شاخص‌های شکنندگی با مدول چقرمگی نشان دهنده ارتباط قوی بین شاخص شکنندگی B3 (ضرایب تعیین 83/0 R2 = و 46/5 = RMSE) و شاخص شکنندگی B4 (ضرایب تعیین 83/0R2 = و 85/3 = RMSE) با مدول چقرمگی سنگ‌ها است. رابطه آماری بین مدول چقرمگی سنگ و انرژی ویژه برش نشان دهنده ارتباط قوی (85/0R2 =) بین این دو پارامتر می‌باشد. به طوری که با افزایش مدول چقرمگی، میزان انرژی ویژه برش سنگ افزایش می‌یابد. در این تحقیق با استفاده از مدول چقرمگی سنگ‌ها، مقدار انرژی ویژه برش آن‌ها تخمین زده شده است.

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation brittleness indices of rocks, implication for estimating their toughness modulus

نویسندگان [English]

  • Mojtaba Heydari 1
  • seyed sajjad karrari 2
  • Jafar Khademi Hamidi 3
  • Ebrahim Sharifi tashnizi 4
1 Associate Prof. of Engineering Geology Bouali University
2 Department of Geology, Faculty of Science, Bu-Ali Sina University, Hamedan
3 Department of Mining Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran
4 Department of Geology, Faculty of Science, Ferdosi University, Mashhad
چکیده [English]

Brittleness and modulus of toughness are among the most important inherent properties of rock, which are determinative for rock excavation operations. In this study, mechanical properties of granite, granodiorite, dolomite, hornfels and marble were studied in the area of Glass water supply tunnel near the Naghadeh city (NW Iran). The stress-strain curve area and rocks strength properties were applied to calculate 13 brittleness indices and modulus of toughness. Statistic relationships between brittleness indices and toughness of modulus suggest strong correlation between B3 brittleness index (R2= 0.83 and RMSE= 5.46 coefficients) and B4 brittleness index (R2= 0.83 and RMSE= 3.85) respectively with modulus of toughness. The statistical relationship between modulus of toughness and specific energy indicates a strong correlation (R2= 0.85). The modulus of toughness and brittleness are useful parameters for estimating specific energy of rock cutting. Since the modulus of toughness increases with specific energy of rock cutting, it enabled us to estimate the specific energy of rock cutting.

کلیدواژه‌ها [English]

  • brittleness
  • modulus of toughness
  • specific energy
  • Glass tunnel
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