تأثیر سخت کننده‌ها و نحوه‌ی چینش آن‌ها بر پاسخ فرکانسی و لرزه‌ای برج آبگیر در حین ساخت

نوع مقاله : علمی - پژوهشی

نویسندگان

1 گروه مهندسی عمران ، دانشگاه زنجان

2 استادیار، دانشکده مهندسی عمران، دانشگاه زنجان

3 'گروه مهندسی عمران, دانشگاه زنجان

چکیده

در این مطالعه روند اثرات افزودن سخت‌کننده بر پاسخ فرکانسی و لرزه‌ای برج آبگیر در زمان ساخت مورد بررسی و تحلیل قرار گرفته است. بدین منظور و برای بررسی بهتر اثرات سخت‌کننده‌ها از دو نوع سخت‌کننده‌ی افقیو قائم در تعداد و ترازهای ارتفاعی مختلف استفاده شده است. همچنین این بررسی برای حالاتی که وزن سازه به میزان وزن سخت‌کننده‌هایاضافه شده، کاهش یافته نیز مورد بررسی قرار گرفته است. در این تحقیق ابتدا آنالیزفرکانسی این مدل‌ها پس از افزودن سخت‌کننده‌ها انجام گرفته و با مدل اصلی مقایسه شده است که نتایج نشان می‌دهد مقادیر فرکانس اول سازه با اعمال سخت‌کننده‌های طوقی و قائم به ترتیب کاهش و افزایش یافته است که نشان از تأثیرات نوع و تعداد سخت‌کننده‌ها بر پاسخ فرکانسی سازه دارد. در ادامه برای بررسی بهتر اثرات این نوع سخت‌کننده‌ها، برج‌هایآبگیر ساخته شده تحت آنالیز لرزه‌ای قرار گرفته‌اند و نتایج حاصل نشانگر آن است کهمیزان تغییر‌مکان‌ها و تنش‌ها برای حالاتی که سخت‌کننده‌ی افقی در نظرگرفته شده است، افزایش یافته و نیز برای حالات برج آبگیر با سخت‌کننده قائم مقادیر تغییرمکان‌ها کاهش یافته و مقادیر تنش بسته به تراز ارتفاعی سخت‌کننده‌ها روند نزولی به خود می‌گیرد. نتایج حاکی از اهمیت اثرات سخت‌کننده‌ها برپاسخ فرکانسی و لرزه‌ای برج آبگیر داشته و ضرورت بررسی این حالات را نشان می دهد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Influence of Stiffeners and their arrangement on frequency and seismic response of intake tower during construction

نویسندگان [English]

  • Ehsan Teymoori 1
  • saeed abbasi 2
  • Amir Javad moradloo 3
1 Department of Civil engineering, University of Zanajn
2 Assistant Professor, School of Civil Engineering, University of Zanjan, Zanjan, Iran
3 Department of Civil engineering, University of zanjan
چکیده [English]

In this study, the effects of added stiffeners on the frequency and seismic response of an intake tower during construction period are investigated. For this purpose and in order to better investigate the effects of stiffeners, two types of circular and vertical stiffeners have been used in different numbers and height levels. It is also examined for situations where the weight of the structure is reduced in the amount of the added stiffeners' weight.In this study, the frequency responseof these models after adding the stiffeners was compared with the original model. The results show that the initial frequency of the structures is reduced and increased by the use of circular and vertical stiffeners, respectively. This indicates the effects of type and number of stiffeners on the frequency response of the structure. In order to better investigate the effects of these types of stiffeners, examined intake towers have been subjected to seismic excitation. The results show that the displacements and stresses are increased for the states in which circular stiffeners are considered. Also, for the intake towers with the vertical stiffeners, the values of displacements are decreased and the stress values are adjusted depending on the level of stiffeners. The results indicate the importance of the effects of stiffeners on the frequency response and seismic response of the intake tower and indicate the necessity of investigating these states.

کلیدواژه‌ها [English]

  • Intake Tower
  • Circular Stiffener
  • Vertical Stiffener
  • Frequency Analysis
  • Seismic Analysis
  • Finite Element Method
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