بررسی و ارزیابی آزمایشگاهی کمانش اعوجاجی در تیرهای فولادی با ارتفاع جان متغیر تحت بار متمرکز

نوع مقاله : مقاله کامل پژوهشی

نویسندگان

گروه مهندسی عمران، دانشکده فنی، دانشگاه ارومیه

10.22034/ceej.2025.64119.2391

چکیده

در این پژوهش، ظرفیت کمانش اعوجاجی در تیرهای فولادی با جان متغیر تحت بارگذاری متمرکز به‌صورت آزمایشگاهی و عددی مورد بررسی قرار گرفته است. کمانش اعوجاجی، به‌عنوان یک پدیده پیچیده و ترکیبی از کمانش موضعی و جانبی- پیچشی، تأثیر قابل‌ توجهی بر ناپایداری تیرهای جدار نازک دارد. در این مطالعه، سه نمونه تیر فولادی با ارتفاع جان متغیر ساخته و تحت آزمایش قرار گرفتند. نتایج نشان داد که افزایش ارتفاع جان و تغییرات پیوسته در طول تیر تأثیر مهمی بر کاهش ظرفیت کمانشی دارد. همچنین، تحلیل‌های عددی با استفاده از نرم‌افزار ABAQUS نتایج آزمایشگاهی را تأیید کرد و نقش مهمی برای ناکاملی‌های هندسی و نوع بارگذاری در رفتار کمانشی تیرها مشخص شد. این پژوهش نشان می‌دهد که روش‌های آیین‌نامه‌ای فعلی برای پیش‌بینی دقیق ظرفیت کمانش اعوجاجی کافی نیستند و نیاز به بهبود دارند. درنهایت، پیشنهادهایی برای تحقیقات آینده جهت بهبود مدل‌های تحلیلی و طراحی ارائه شده است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental Investigation into Distortional Buckling Behavior of Web-Tapered I-Section Steel Beams Under Point Load

نویسندگان [English]

  • Mahdi Haghdoust Qahramanlou
  • Hossein Showkati
Civil Engineering Group, Faculty of Engineering, Urmia University, Urmia, Iran
چکیده [English]

     This research investigates the distortional buckling capacity in steel beams with variable web height under concentrated loads using both experimental and numerical approaches. Distortional buckling, a combination of local and lateral-torsional buckling, significantly influences the instability of thin-walled beams. In this study, three variable-height steel beam specimens were fabricated and tested. The results revealed that increasing the web height and continuous changes along the beam length significantly reduce the buckling capacity. Numerical analyses using ABAQUS also confirmed the experimental findings, highlighting the importance of geometric imperfections and loading types on buckling behavior. This study demonstrates that current code methods are insufficient for accurately predicting distortional buckling capacity and require improvement. Finally, suggestions for future research to improve analytical models and design methods are presented.

کلیدواژه‌ها [English]

  • Distortional buckling
  • Web-tapered
  • Steel beam
  • Experimental
  • Numerical analysis
  • ABAQUS
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