شبیه‌سازی عددی تأثیر پارامترهای اساسی بر توزیع تنش‌های القایی طی فرایند تخریب اول در استخراج جبهه‌کار طولانی

نوع مقاله : علمی - پژوهشی

نویسندگان

1 فارغ التحصیل دکترای استخراج معدن

2 استاد دانشگاه صنعتی شاهرود

3 University of Southern Queensland

چکیده

فرآیند تخریب در روش استخراج جبهه‌کار طولانی به طور مستقیم بر پایداری و پیوستگی عملیات استخراج تاثیر می‌گذارد. از این رو پیش‌بینی رفتار تخریبی سقف از دو دیدگاه گام‌های تخریب و مقدار تنش‌های القایی ایجاد شده در طی آن مساله‌ای ضروری در طراحی پروژه‌های استخراج جبهه‌کار طولانی است. در این راستا فرآیند تخریب اول که در آن گام تخریب و تنش‌های القایی بیش از تخریب دوره‌ای است، اهمیت ویژه‌ای دارد. بر این اساس در این مقاله به بررسی تنش‌های القایی ناشی از فرآیند تخریب اول از طریق شبیه‌سازی عددی گسسته پرداخته شده است. برای این منظور تاثیر تغییرات 5 پارامتر مقاومت کلی سقف بلاواسطه به صورت تابعی از مقاومت فشاری تک محوری لایه‌ها و ضخامت آن‌ها، ارتفاع سقف بلاواسطه، فاصله لایه‌بندی در سقف بلاواسطه، عمق معدنکاری و نسبت تنش‌های برجا بر روی بیشینه تنش‌های القایی قائم و افقی جلو و پشت جبهه‌کار با استفاده از نرم‌افزار UDEC مجموعا برای 62 مدل تحلیل شده است. نتایج حاصل شده نشان می‌دهد که به ‌جز برای نسبت تنش‌های برجا، روند تغییرات فشارهای پایه‌ای قائم و افقی جلویی و عقبی نسبت به تغییرات پارامترها یکسان است. همچنین رابطه تمام پارامترها با تنش‌های پایه‌ای به ‌جز ارتفاع سقف بلاواسطه به صورت مستقیم است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical simulation of influence parameters on induced stresses distribution during first weighting process of longwall mining

نویسندگان [English]

  • Sadjad Mohammadi 1
  • mohammad Ataei 2
  • Reza Kakaie 2
  • ali mirzaghorbanali 3
1 shahrood university of technology
2 shahrood university of technology
3 University of Southern Queensland
چکیده [English]

Investigation of first weighting process due to greater caving span and higher induced stresses when compared to the periodic ones is imperative in the planning stage of a longwall coal mining project. Hence, a reliable prediction of caving span and abutment pressure during this process has major role in stability analysis of operation. This paper presents the results of numerical simulation intended to examine stress distribution in terms of peak abutment pressures during first weighting process in longwall mining. Longwall mining was simulated by incorporating Universal Distinct Element Code (UDEC) to investigate the effects of five critical parameters included roof strata uniaxial compressive strength, immediate roof height, spacing of bedding planes and mining depth and in-situ stresses ratio on vertical and horizontal peak abutment pressures. The results showed that relationships between all critical parameters with the exception of in-situ stresses ratio and front and rear abutment pressures in vertical and horizontal directions are the same. In addition, it was concluded that all parameters have a direct relationship with the rear and front abutment pressures whereas this relationship is indirect for the immediate roof height and the extraction height.

کلیدواژه‌ها [English]

  • Longwall mining
  • First weighting process
  • induced stresses
  • discontinuous numerical simulation
  • Universal Distinct Element Code (UDEC)
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