بررسی پارامترهای میدان تنش در یک صفحه‌ تقویت شده ترک دار تحت مود ترکیبی I/II

نوع مقاله: مقاله پژوهشی

نویسندگان

1 عضو هیات علمی / دانشکده مهندسی هوافضا، دانشگاه صنعتی خواجه‌نصیرالدین طوسی

2 کارشناس ارشد / دانشکده مهندسی هوافضا، دانشگاه صنعتی خواجه‌نصیرالدین طوسی

چکیده

صفحات نازک تقویت‌شده به‌طور گسترده‌ای در صنایع مهندسی به‌کار گرفته می‌شوند. وجود ترک عامل مهمی در واماندگی این‌گونه سازه‌هاست که می‌تواند به تخریب سازه در زمانی کمتر نسبت به کارکرد واقعی آن در حالت بدون ترک منجر شود. در این مقاله، ضرایب شدت تنش مودهای اول و دوم شکست برای صفحة نازک تقویت‌شدة ایزوگرید با شبکه‌بندی لوزی و تقویت‌کننده‌هایی با مقطع T شکل، تحت شرایط بارگذاری تک‌محوری و دومحوری مورد مطالعه قرار گرفته است تا تفاوت آن با صفحات ساده مشخص شود. صفحة تقویت‌شدة مستطیلی دارای 12 ریب تقویتی با زاویة 60 درجه نسبت به محور عرضی است. به‌منظور مدلسازی صفحات تقویت‌شده، صفحه و تقویت‌کننده‌ها به‌صورت یکنواخت با هم مونتاژ شده‌اند. مدلسازی و تحلیل با استفاده از نرم‌افزار اجزای محدود آباکوس صورت گرفته و تأثیر پارامترهای مختلف مثل طول و زاویة ترک و همچنین حالات متنوع بارگذاری بر ضرایب شدت تنش در صفحة تقویت‌شدة مشبک بررسی می‌شود. نتایج نشان می‌دهد که هر یک از متغیرهای مورد بررسی تأثیر قابل‌توجهی بر ضرایب شدت تنش دارند. همچنین با تغییر زاویة ترک و یا در حالت‌های مختلف بارگذاری، ضرایب شدت تنش در صفحة مشبک تقویت‌شده می‌توانند دارای مقادیر منفی باشند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of stress field parameters in a cracked stiffened plate under mixed mode I/II

نویسندگان [English]

  • Mahnaz Zakeri 1
  • Abolfazl Jafari 2
چکیده [English]

Thin reinforced plates are utilized widely in many fields of engineering industries. Existence of crack is an important factor of failure in such structures, which can lead to structural damage in less time than its real function without the crack. In this paper, stress intensity factors for mode one and mode two of fracture are studied in isogrid thin plate reinforced with diamond lattice and stiffeners with T-shaped cross section under uniaxial and biaxial loading conditions to find the difference with simple plates. The rectangular reinforced plate has 12 stiffener ribs with angle of 60 degrees regarding to transverse axis. In order to model the reinforced sheet, plates and stiffeners are assembled together uniformly. Modeling and analysis are performed using Abaqus finite element software; and the effect of various parameters such as length and angle of the crack and also, the different loading conditions on stress intensity factors in reinforced lattice plane are investigated. The results show that each of the investigated variables has a significant impact on stress intensity factors. Also, by changing the angle of crack or at different loading conditions, the stress intensity factors can have negative values in lattice reinforced thin plate.

کلیدواژه‌ها [English]

  • mixed mode I/II
  • central crack
  • stiffener
  • isogrid
  • diamond lattice

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