بررسی تأثیر زلزله های میدان دور و نزدیک بر پاسخ لرزه ای سدهای بتنی وزنی کنترل شده با میراگر لاستیکی

نوع مقاله : علمی - پژوهشی

نویسندگان

1 گروه عمران، دانشکده فنی، دانشگاه محقق اردبیلی، اردبیل، ایران

2 استادیار گروه مهندسی عمران، دانشکده فنی، دانشگاه محقق اردبیلی، اردبیل، ایران

3 فارغ‌التحصیل کارشناسی ارشد مهندسی عمران، دانشکده فنی، دانشگاه محقق اردبیلی، اردبیل، ایران

چکیده

بخش زیادی از نیروی دینامیکی اعمالی بر سد ناشی از نیروی هیدرودینامیکی تولید شده در مخزن در اثر اندرکنش سد و مخزن می‌باشد. ماهیت و نحوه اعمال این نیرو در رکوردهای میدان دور و نزدیک زلزله بر سازه‌ها متفاوت بوده و سازه‌های مختلف در برابر هریک از انواع رکوردهای مذکور رفتار متفاوتی دارند. یکی از راهکارهای کنترل لرزه‌ای سد بتنی وزنی استفاده از میراگرهای لاستیکی در مرز سد و مخزن جهت کاهش فشار هیدرودینامیکی وارده بر سد می‌باشد. لذا در این تحقیق برای بررسی تأثیر میراگرلاستیکی بر نمایش لرزه‌ای سد بتنی وزنی از دو رکورد میدان نزدیک و دو رکورد میدان دور زلزله‌ برای تحلیل‌ها استفاده شده است. پاسخ‌های خروجی مورد بررسی شامل مقادیر حداکثر تغییر مکان افقی تاج سد و تنش کششی اصلی در پاشنه می‌باشد که به عنوان پاسخ‌های بحرانی انتخاب شده‌اند. برای مدل‌سازی و تحلیل از نرم افزار انسیس که مبتنی بر روش اجزای محدود می‌باشد، استفاده شده و برای حل معادلات دینامیکی از روش نیومارک استفاده شده است. نتایج حاصل از تحلیل تأثیر مثبت لایه ایزولاسیون را در کاهش پاسخ‌های لرزه‌ای وارده بر سد در هر دو میدان دور و نزدیک زلزله، نشان می‌دهد. علاوه بر این می‌توان گفت میراگرلاستیکی در میدان نزدیک عملکرد بهتری نسبت به میدان دور دارد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of the Effect of Near and Far Fault Earthquake on Seismic Response of Controlled Concrete Gravity Dams with Rubber Damper

نویسندگان [English]

  • Majid Pasbani Khiavi 1
  • Mortaza Ali Ghorbani 2
  • Arash Ghaed Rahmati 3
1 Department of Civil Engineering, Faculty of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran
2 Assistant professor of civil engineering, Faculty of engineering, University of Mohaghegh Ardabili
3 M. Sc. Graduated in civil engineering, Faculty of engineering, University of Mohaghegh Ardabili
چکیده [English]

A large part of the dynamic force applied to the dam is the hydrodynamic force generated in the reservoir due dam and reservoir interaction. The nature and method of applying this force in near and far fault earthquake records on structures was different and structures behave differently against each of these types of records. One of the solutions to control the seismicity of the concrete gravity dam is to use seismic dampers at the interface of the dam and the reservoir to reduce the hydrodynamic pressure on the dam. Therefore, in this study to investigate the effect of damping on the seismic performance of a concrete gravity dam, two near fault and two far fault earthquake records were used for the analysis. Output responses including maximum response of dam crest displacement and 1st principle stress at heel have been selected as critical responses. Ansys software, based on finite element method, was selected for dam modeling and seismic analysis and Newmark method has been used to solve the dynamic equation. The results of the analysis show the positive effect of the isolation layer in reducing the seismic responses to the dam in both far and near earthquake fields. In addition, it can be said that rubber damper performs better in the near fault than in the far fault.

کلیدواژه‌ها [English]

  • Concrete gravity dam
  • Rubber damper
  • Interaction
  • Seismic control
  • Near and far fault
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