تحلیل پارامتریک رفتارغیرخطی اعضای لوله‌ای شکل تحت بار جانبی دینامیکی

نوع مقاله : مقاله پژوهشی

نویسندگان

چکیده

بررسی رفتار غیر خطی اعضای لوله ای شکل تحت تأثیر بار جانبی که بصورت دینامیکی وارد شود، موضوع مقاله حاضر است. با بررسی منحنی های نیرو –  تغییر مکان مدل فرضی که توسط روشهای عددی بدست آمده مشخص شد که پارامترهای مختلف از جمله ضخامت، پیش بارگذاری محوری و شرایط انتهایی تاثیر بسزایی بر ظرفیت باقیمانده عضو لوله­ای تحت اثر ضربه جانبی دارد. بر این اساس روش مناسبی برای محاسبه ظرفیت باقیمانده عضو لوله ای شکل ارائه شده و نتایج در قالب یک نمودار با روشهای پیشین مقایسه شده است.  تفاوت نتایج تحلیل شبه استاتیکی تحقیقات گذشته در این زمینه با نتایج دینامیکی در این تحقیق مقایسه و برای سنجش دقت مدل پیشنهادی، نتایج بدست آمده با نتایج موجود در مقالات و آزمایشات عملی در این زمینه مورد مقایسه قرار گرفته است.

کلیدواژه‌ها


عنوان مقاله [English]

Parametric Analysis of Nonlinear Behavior of Tubular Members under Lateral Dynamic Loads

نویسندگان [English]

  • Mohammad Reza Bahaari
  • Babak Mehdizadeh Rahimi
چکیده [English]

Non-linear behavior of tubular members with axial pre-load is studied against dynamic lateral impact. Nonlinear behavior of these members would be due to material non-linearity (NLM) or geometric non-linearity (NLG). Study of the curves of load displacement of arbitrary tubular member by analytical solutions indicates that changes in parameters such as pipe thickness, magnitude of axial pre-loading, and end conditions of the member under study has significant affect on their residual strength subject to application of dynamic lateral impact. Based on this analysis, a reliable method for calculation of residual strength of tubular member is proposed. The results of the comparison between the two methods using quasi-static and dynamic analyses are shown in a diagram. In addition, to measure the reliability of the model it has been validated using available test results from the literatures.

کلیدواژه‌ها [English]

  • Tubular members
  • Lateral dynamic load
  • nonlinear behavior
  • Residual strength
  • Offshore structures
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