ارزیابی حساسیت پاسخ یک پل کابلی دارای جداساز لرزه‌ای تحت زلزله‌ ی نزدیک به گسل نسبت به تغییرات مصالح

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشگاه صنعتی نوشیروانی بابل

چکیده

عوامل متعددی می‌تواند بر پاسخ سازه‌ها تحت بارهای لرزه‌ای مؤثر باشد. مشخصات مصالح مورد استفاده می‌تواند نسبت به پارامترهای مورد نیاز در طرح سازه‌ها متفاوت باشد. این تفاوت می‌تواند بر پاسخ سازه‌ها مؤثر باشد. در این تحقیق سعی شده است تا با استفاده از روش‌ها تحلیل حساسیت اثر تغییر مشخصات مصالح بر پاسخ لرزه‌ای یک پل کابلی معلق مجهز به جداساز RNC بررسی شود. یک پل کابلی با و بدون جداساز RNC پس از مدلسازی اولیه تحت یک زلزله‌ی سنفرنادو به صورت دینامیکی غیرخطی تحلیل شده است. سپس تأثیر متغیرهای تصادفی بر پاسخ این سازه‌ها با استفاده از روش‌های حساسیت سنجی مونت‌کارلو و مرتبه اول مسمان دوم بررسی شده است. در نهایت دقت روش تحلیل FOSM نسبت به روش مونت‌کارلو ارزیابی شده است. دو پارامتر برش پایه و بیشینه جابجایی عرشه به عنوان پاسخ‌های سازه در نظر گرفته شده است. نتایج نشان می‌دهد در بین مشخصات مصالح مقاومت نهایی بتن، تنش تسلیم آرماتور و مدول الاستیسیته کابل‌ها بیشترین تأثیر را بر پاسخ لرزه‌ای این سازه‌ها دارد. همچنین میزان حساسیت این پارامترها در پل جداسازی شده کمتر از پل بدون جداساز است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Sensitivity Analysis of Response of a Cable Bridge with Base Isolation to Material Variation under Near Earthquake

نویسندگان [English]

  • Hamidreza Tavakoli
  • majid moradi
Civil Engineering, Babol Noshirvani University of Technology
چکیده [English]

Several factors can influence the response of structures under seismic loading. The specifications of the materials used may differ from the parameters required in the design of structures. This difference can affect the response of structures. In this study, we have tried to investigate the sensitivity analysis of the effects of changing the properties of materials on the seismic response of a suspended cable bridge equipped with RNC isolator. A cable bridge with and without the RNC isolation has been dynamically analyzed after initial modeling under a Sanfernado earthquake record. Then, the effect of random variables on the response of these structures is investigated using Monte Carlo and first order second moment sensitivity methods. Finally, the accuracy of FOSM analysis compared to Monte Carlo method. Two parameters of base shear and maximum deck displacement are considered as structural responses. The results show that among the material characteristics, final strength properties of concrete, reinforcement yield stress and modulus of elasticity of cables have the most influence on the seismic response of these structures. Also, the sensitivity of these parameters in the isolated bridge is lower than that of the non-separated bridge.

کلیدواژه‌ها [English]

  • Cable bridge
  • RNC isolator
  • Sensitivity analysis
  • Random Variation
  • Near Reacord
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