مدل‌سازی ترک با استفاده از توابع درون‌یاب غنی‌ساز پوشش

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار دانشکده مهندسی عمران -دانشگاه تربیت دبیر شهید رجائی-لویزان- تهران- ایران

2 دانشجوی دکترا

چکیده

روش عددی پوشش، یک روش بر پایه افراز واحد می‌باشد که با استفاده از درجات متناسبی از توابع غنی سازی در نقاط دارای خطای باال باعث افزایش دقت می‌گردد. در این روش توابع درون‌یاب غنی ساز به نقاطی که فاقد دقت کافی‌اند ، اعمال می‌گردند. کارآمدی روش پوشش تا به حال برای بسیاری از مسائل مهندسی به اثبات رسیده است. ناپیوستگی جابجایی در مرز ترک توسط توابع هویساید مدل می‌گردد و همچنین توابعی برای مدل کردن ضریب شدت تنش نوک ترک به توابع درون‌یاب پوشش اضافه می‌گردد. در این مقاله توانمندی روش پیشنهادی با ارزیابی پارامترهای شکست برای مثال‌های متنوعی از ترک‌های ثابت مورد بررسی قرار گرفته است. صحت‌یابی و توانمندی روش با سه مثال عددی شامل ترک مرکزی، ترک لبه و ترک مایل مرکزی با زوایای مختلف مورد بررسی قرار گرفته است. مقایسه جواب‌های حاصل از روش پیشنهادی با جواب دقیق و روش‌های دیگر محققان در حوزه مسائل الاستیسیته خطی، حکایت از کارایی و دقت قابل قبول روش پیشنهادی دارد.

کلیدواژه‌ها


عنوان مقاله [English]

The Analyzing of the Discontinuity Problem by Enriched Interpolation Covers

نویسندگان [English]

  • Hamed Arzani 1
  • Elham Khoshbavar Rad 2
1 Civil Eng. Dep. Shahid Rajaee Teacher Training Univ. Lavizan. Tehran. Iran
2 Phd. Student
چکیده [English]

The cover numerical method is based on unit partitioning, using enrichment functions of various orders, this method increases the accuracy at every point. In this method, unknowns are added to the points of not sufficient accuracy, regarding to the enrichment interpolating functions. The cover method has proved its efficiency in a variety of engineering problems. The Heaviside function models the displacement discontinuity on the crack boundary. Such functions are added to model the coefficient of stress intensity for the tip of the crack. In this paper, the proposed method has been verified by evaluating crack parameters for instances containing fixed fractures. In the end, three numerical instances containing central crack, edge crack and inclined crack with three different cracks are inspected. The comparison of the results from the presented method, with exact solutions and other solutions in the area of linear elasticity, proves the reliability and accuracy of the proposed method.

کلیدواژه‌ها [English]

  • The interpolating cover Functions method
  • Discontinuous fields
  • Heaviside function
  • Crack
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