نشریه مهندسی عمران امیرکبیر

نشریه مهندسی عمران امیرکبیر

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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