اُلگوی بزرگنمایی لرزه‌ای سطح زمین در حضور تونل‌های دوقلوی دایره‌ای بدون پوشش در برابر امواج مهاجم SH

نوع مقاله: مقاله پژوهشی

نویسندگان

گروه مهندسی عمران، واحد زنجان، دانشگاه آزاد اسلامی، زنجان، ایران.

چکیده

در این مقاله، الگوی بزرگنمایی لرزه‌ای سطح زمین در حضور تونل‌های دوقلوی دایره‌ای بدون پوشش، در برابر امواج مهاجم لرزه ای برون صفحه نشان داده شده است. از روش اجزای مرزی نیم‌صفحه در حوزه‌ی زمان که پیشتر برای تونل‌های زیر‌زمینی منفرد توسعه داده شده بود، جهت تحلیل لرزه‌ای مدل مفروض بهره گرفته شده است. ابتدا، ضمن اشاره‌ی مختصر به فرمول‌بندی روش پیشنهاد شده و ارائه‌ی یک مثال صحّت‌سنجی، با در نظر گرفتن پارامترهای عمق مدفون تونل، فاصله‌ی مابین، زاویه‌ی موج مهاجم و فرکانس پاسخ، به تحلیل حساسیّت و تعیین بزرگنمایی لرزه‌ای سطح زمین اقدام شده است. در‌نهایت، با اتخاذ بزرگنمایی حداکثر در حالات مختلف و برازش از این مقادیر، نتایج به صورت یک سری معادلات خطی و جداول، جمع‌بندی شده است. نتایج نشان می‌دهد، موقعیّت‌های مختلف استقرار تونل‌های دوقلوی مدفون در بافت شهری، بر پاسخ لرزه‌ای سطح زمین، بسیار موثر است. نتایج این تحقیق می‌تواند در تکمیل و تدقیق آیین‌نامه‌های موجود، پیرامون موضوع پهنه‌بندی سطح زمین در حضور تونل‌های دوقلو، مورد استفاده قرار گیرد.

کلیدواژه‌ها


عنوان مقاله [English]

Seismic amplification pattern of the ground surface in presence of twin unlined circular tunnels subjected to SH-waves.

نویسندگان [English]

  • Mehdi Panji
  • Saeed Mojtabazadeh-Hasanlouei
Assistant professor of civil engineering group
چکیده [English]

In this paper, the amplification pattern of the ground surface is presented in presence of twin unlined circular tunnels subjected to SH-waves. To analyze the assumed seismic model, a half plane time-domain Boundary Element Method (BEM) was used which has been previously developed for single sub-surface tunnels. First, after presenting a brief formulation of the proposed method and displaying a verification example, the sensitivity analysis was carried out to obtain the seismic amplification pattern of the ground surface by considering the key parameters including tunnels buried depth, interval distance, incident wave angle and response frequency. Finally, by collecting the maximum amplification of different scenarios and applying linear fit on the obtained values, the results were summarized as series of linear equations and tables. The results showed that different situations of buried twin tunnels in urban fabric was very effective on the seismic response of surface. The results of this research can be used to completing and increasing the accuracy of existing codes around the subject of ground surface zonation in presence of twin tunnels.

کلیدواژه‌ها [English]

  • Amplification pattern
  • Half-plane BEM
  • SH-wave
  • Time-domain
  • Twin circular tunnels
 

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