تعیین صفحه معرف دسته درزه‌ها با رویکرد افزایش قابلیت اطمینان

نوع مقاله : علمی - پژوهشی

نویسندگان

1 دانشجوی دکتری مکانیک‌سنگ، بخش مهندسی معدن، دانشکده فنی و مهندسی، دانشگاه شهید باهنر کرمان، کرمان، ایران

2 استادیار بخش مهندسی معدن، دانشکده فنی و مهندسی، دانشگاه شهید باهنر کرمان، کرمان، ایران

3 دانشیار دانشکده مهندسی معدن، دانشگاه تهران ، تهران، ایران دانشیار بخش مهندسی معدن، دانشکده فنی و مهندسی ، دانشگاه شهید باهنر کرمان، کرمان، ایران

چکیده

ارایه تخمینی مطمئن از جهت‌داری صفحه ناپیوستگی حاصل از درزه‌های متعلق به یک دسته درزه اهمیت ویژه‌ای در مطالعات و تحلیل‌های مکانیک‌سنگ دارد. روش‌های رایج در تعیین این جهت‌داری به صورت قطعی و بدون در نظر گرفتن قابلیت اطمینان موجود در محاسبات ارایه شده‌اند. امروزه در علوم مهندسی روش‌های آماری و احتمالاتی برای بررسی عدم اطمینان موجود در داده‌ها و همچنین اعتبارسنجی جواب‌ها و روش‌های محاسباتی، به ‌طور گسترده مورد استفاده قرار می‌گیرند و تاکید آن‌ها بر مشخص کردن موارد مجهول و ناشناخته موجود در تحلیل‌ها است. در این مطالعه روشی جدید در محاسبه صفحه ناپیوستگی حاصل از یک سری درزه متعلق به یک دسته درزه بر مبنای روش احتمالاتی شبیه‌سازی مونت کارلو ارایه شده است و برای بررسی آن، نتایج حاصل با روش برداری رایج مقایسه شده است. بررسی دو روش قطعی و احتمالاتی با تحلیل عددی المان مجزا نشان داد که روش جدید به دلیل در نظر گرفتن افزایش قابلیت اطمینان و شبیه‌سازی بر مبنای تمامی حالات از طریق تعیین توابع توزیع آماری و نمونه‌برداری تصادفی از آن‌ها، نسبت به روش رایج مناسب‌تر است. این برتری در مورد جهت‌داری‌های توسعه یافته در دو سوی مرز شبکه به‌ طور بارز دیده می‌شود. همچنین بررسی تعیین جهت شیب و مقدار شیب صفحه ناپیوستگی حاصل از یک دسته درزه نشان داد که در شرایطی که قطب‌ درزه‌های یک دسته درزه در یک سوی شبکه استریونت قرار ‌گیرند، محاسبات روش رایج، قابلیت اطمینان بیش از 98 درصد برای جهت شیب و مقدار شیب دارند. در حالی که این محاسبات برای جهت‌داری‌هایی که در دو سوی مرز شبکه باشند، قابلیت اطمینان آن‌ها به بیش از 95 درصد برای جهت شیب و بیش از 87 درصد برای مقدار شیب کاهش خواهد یافت.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Development of a new approach to determine the representative joint set with enhanced reliability

نویسندگان [English]

  • Mojtaba Rabiei Vaziri 1
  • Hossein Tavakoli 2
  • Mojtaba Bahaaddini 3
1 PhD Student in Rock Mechanics, Shahid Bahonar University of Kerman
2 Department of Mining Engineering, Faculty of Engineering, Shahid Bahonar University of Kerman
3 Department of Mining Engineering, Faculty of Engineering, Shahid Bahonar University of Kerman
چکیده [English]

A reliable estimation of the discontinuity orientation of a joint set is of great importance in rock mechanics studies and interpretations. Common approach for determination of the joint set orientation is based on deterministic approach without considering the reliability of calculations. Nowadays, statistical and probabilistic methods are widely used to investigate uncertainties in the input data as well as validating the output of calculations and outputs where the emphasis is placed on identification of unknowns in analyzes. In this study a new method was presented for calculating the representative discontinuity plane of a joint set based on the Monte Carlo simulation method and the results were then compared with the conventional method. Evaluation of deterministic and probabilistic methods were carried out using distinct element method which showed that the proposed method is more suitable compared to the conventional method due to enhanced reliability in calculation as well as simulating based on considering the statistical distribution function and sampling from them. This advantage can be clearly seen for orientations fall in the edge of hemisphere projection. Furthermore, results of this study showed that when the joints are located on one side of the stereonet, the conventional method has a reliability more than 98%. in determining the dip and dip direction of representative discontinuity plane of a joint set while for orientations fall in the edge of hemisphere projection the reliability is reduced to more than 95% for the dip direction and more than 87% for the dip.

کلیدواژه‌ها [English]

  • Probabilistic analysis
  • Reliability analysis
  • Discontinuities orientation
  • Statistical distribution function
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