بررسی تجربی جذب انرژی پروفیل‌های مربعی تحت بارگذاری دندانه‌ای چندگانه

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشکده مهندسی مکانیک و هوافضا، دانشگاه صنعتی شیراز

چکیده

در این تحقیق به مطالعه تجربی جذب انرژی و تغییر شکل پروفیل‌های جدارنازک با سطح مقطع مربعی تحت بارگذاری دندانه‌ای چندگانه پرداخته شده است. هدف اصلی از انجام این تحقیق بررسی اثر تعداد دندانه‌ها و همچنین قطر و فاصله‌ی بین دندانه‌ها بر پارامترهای جذب انرژی است. در ابتدا پروفیل‌های مربعی آلومینیوم با طول مشخص تهیه شد و همچنین یک مجموعه دندانه قابل تنظیم نیز جهت اعمال بارگذاری دندانه‌ای چندگانه ساخته شد. سپس بارگذاری شبه استاتیکی با نرخ بارگذاری ثابت بر روی نمونه‌ها انجام گرفت. در نحوه‌ی بارگذاری، نمونه‌ها بین یک فک نسبتا صلب و یک مجموعه‌ی دندانه قابل تنظیم قرار گرفت. نمودارهای نیرو-جابه‌جایی نمونه‌ها به دست آمد و پارامترهای جذب انرژی محاسبه شد. مقایسه‌ی نتایج تجربی در حالت یک‌دندانه و دودندانه نشان دهنده افزایش قابل توجه جذب انرژی حالت دودندانه نسبت به یک دندانه بود. برای بارگذاری با دو دندانه، با افزایش فاصله دندانه‌ها از هم، نمودارهای نیرو-جابه جایی به مراتب بالاتر از حالت یک دندانه قرار گرفت و به حالت دو دندانه مجزا نزدیک شد. همچنین با افزایش قطر و فاصله‎ی بین دندانه‌ها به دلیل ایجاد لولای پلاستیک بزرگتر، میزان جذب انرژی حدود 20تا 60درصد افزایش یافت.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental Study of Energy Absorption of Square Column under Multi-Indentation Loading

نویسندگان [English]

  • J. Rouzegar
  • M. R. Keshavarz
  • H. Assaee
Department of Mechanical and Aerospace Engineering, Shiraz university of Technology, Shiraz, Iran
چکیده [English]

This research deals with experimental investigation on energy absorption and deformation of thin walled square columns under multi-indentation loading. The main goal of this research is to examine the effect of number and diameter of indenters and distance between them on the energy absorption parameters. First, square aluminum specimens with specific lengths were prepared and also an adjustable fixture for applying multi-indentation loading was fabricated. Then the indentation loading were applied on the specimens during a quasi-static condition with a constant loading rate. During loadings, the specimens were located between an almost rigid platen and the adjustable indenters. The load-displacement diagrams of specimens were obtained and the energy absorption parameters were calculated. The results indicate that the amount of absorbed energy in multi-indentation process increases significantly respect to single-indentation. By increasing the distance between indenters in multi-indentation loading, the load- displacement diagram shifts upward and moves toward the twice of single-indentation diagram. Also, by increment of diameter of indenters and distance between them, the amount of absorbed energy increases 20-60% due to formation of bigger plastic hinges.

کلیدواژه‌ها [English]

  • Experimental study
  • Energy absorption
  • Thin-walled column
  • Indentation loading
  • Multi-indentation
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