مدلی برای تخمین مقاومت پیوستگی نسبی تیرهای بتن مسلح با میلگردهای وصله‌دار خورده شده با در نظر گرفتن c/db

نوع مقاله : پژوهشی

نویسندگان

1 دانشگاه سیستان و بلوچستان

2 سیستان و بلوچستان

چکیده

خوردگی ناحیۀ وصله موجب تغییر مقاومت پیوستگی می­شود. نسبت مقاومت پیوستگی در حالت خورده شده به مقدار مقاومت پیوستگی متناظر آن در شرایط عدم وجود خوردگی، مقاومت پیوستگی نسبی نامیده می­شود. نتایج مقاومت پیوستگی نسبی در آزمایش­های بیرون­کشیدگی (Pullout)، میلگرد درگیر در بتن (Tension stiffening) و تیرها با میلگردهای وصله­شده (Beams with lap spliced bars) متفاوت است. در مطالعات گذشته نشان داده شد نتایج آزمایش میلگرد درگیر در بتن به نتایج آزمایش تیرها با میلگردهای وصله­شده شباهت بیشتری دارد. در این مطالعه با استفاده از آزمایش‌های میلگرد درگیر در بتن، مدلی برای تعیین مقاومت پیوستگی نسبی میلگردهای خورده شده در شاخۀ نزولی ارائه شده است. در نهایت با بهینه کردن این مدل با استفاده از الگوریتم ژنتیک، از این مدل برای تعیین مقاومت پیوستگی نسبی تیرهای وصله‌دار با میلگردهای خورده شده استفاده می‌شود. مطالعۀ حاضر نشان می‌دهد استفاده از مدل پیشنهادی نتایج بهتری ارائه می­دهد. به‌طوری‌که استفاده از این مدل برای تخمین مقاومت پیوستگی نسبی تیرهای وصله­دار باعث کاهش 16 درصدی خطای کلی نسبت به مدل شیهاتا می­شود.

کلیدواژه‌ها


عنوان مقاله [English]

A Proposed Model for Estimating the Relative Bond Strength of RC Beam with Corroded Lap Spliced Steel Bars, considering c/db

نویسندگان [English]

  • Yaser Moodi 1
  • Mohammad Reza Sohrabi 2
  • Seyed Roohollah Mousavi 1
1 University of Sistan and Baluchestan
2 University of Sistan and Baluchestan
چکیده [English]

Corrosion of lap spliced region causes the bond strength to change. The ratio of the bond strength in the corrotion state to the value of its corresponding in the absence of corrosion is called the relative bond strength. The results of the relative bond strength are different in Pullout test, Tension stiffening test and Beams with lap spliced bars test. The results of theTension stiffening test in the literature is more similar to those of Beams with lap spliced bars. In this study, a model has been proposed using tension stiffening tests, for determining the relative bond strength of corroded steel bars in the descending branch. Finally, this model has been optimized using genetic algorithm for determining the relative bond strength of RC Beam with corroded lap spliced steel bars. The current study shows that using the proposed model will lead to the beter result. The use of proposed model for the estimating the relative bond strength of RC beam with corroded lap spliced steel bars, leads to about 16 percent reduction in total error compared with Shihata model.

کلیدواژه‌ها [English]

  • Reinforce concrete
  • corrosion
  • Bond strength
  • Lap spliced
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