نوع مقاله: مقاله پژوهشی

نویسندگان

1 کارشناسی ارشد، مهندسی عمران و حمل و نقل، دانشگاه اصفهان، اصفهان، ایران

2 استادیار، مهندسی عمران و حمل و نقل، دانشگاه اصفهان، اصفهان، ایران

چکیده

در این مقاله تأثیر تغییرات شرایط محیطی از جمله درجه حرارت و رطوبت محیط بر بار کمانشی ورق‌های لایه‌ای مورد بررسی قرار گرفته است. بدین منظور با در نظر گرفتن اثرات تغییر مشخصات مصالح تشکیل دهنده ورق در اثر دما و رطوبت بر ظرفیت کمانش ورق در شرایط تکیه‌ گاهی مختلف و بارگذاری دو محوره ارزیابی شده است. همچنین تاثیر آسیب جدا شدگی لایه‌ها بر ظرفیت کمانش ورق در حالت‌های مختلف بررسی شده است. روش مورد استفاده جهت محاسبه بار بحرانی ورق‌ها روش نوار محدود بوده که تئوری برشی مرتبه اول بر آن اعمال شده است. در روش نوار محدود از توابع شکل مثلثاتی در جهت طولی نوار و توابع شکل هرمیتی در جهت عرضی برای جابجایی‌های برون صفحه و توابع شکل خطی برای جابجایی‌های درون صفحه استفاده شده است. برای مدل سازی جدا شدگی لایه‌ها، محل و ابعاد جداشدگی با جدا سازی المان‌ها و بازیابی مجدد ماتریس‌های سختی استاندارد، هندسی، نیرویی و جرمی تعیین شده و اثر آن‌ها بر میزان بار بحرانی ورق لایه‌ای در حالت‌های گوناگون ارزیابی شده است. نتایج حاصله بیانگر میزان تغییرات بار بحرانی در دما و رطوبت‌های مختلف و همچنین میزان تاثیر جدا شدگی لایه‌ها می‌باشد.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Buckling analysis of composite cross-ply laminated plates under hygrothermal loads with delaminations using the finite strip method

نویسندگان [English]

  • Farshad Goodarzian 1
  • Hossein Amoushahi 2

1 Department of civil and transportation engineering, University of Isfahan. Isfahan, Iran

2 Department of civil and transportation engineering, University of Isfahan. Isfahan, Iran

چکیده [English]

In this paper the effect of hygrothermal conditions such as temperature and moisture on buckling of composite laminated plates is investigated. For this purpose, the effect of changing in material characteristics with changing in temperature and moisture on buckling capacity of plates with different end conditions and biaxial loading is evaluated. In addition, the effect of delamination of layers on buckling load of plate is studied in different situations. The finite strip method is used in present paper to calculate the critical load of plate considering first shear order deformation theory. In finite strip formulation for evaluating the displacement field of each strip, the trigonometric shape functions is used in longitudinal direction and the Hermitian and linear shape function is used for out of plate and in plane transverse direction, respectively. The place and dimension of delaminating layers is modeled by separating the adjacent elements and reconstructing the standard, geometric, force and mass matrices, so, the critical load of laminated plates is calculated in different situation. The results show that the amount of changing in critical load of laminated plate for different temperatures, moistures and delamination of layers.

کلیدواژه‌ها [English]

  • Buckling
  • Composite plates
  • Finite strip method
  • Hygrothermal loads
  • Delamination

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