ارزیابی پالس معادل حرکات پالس گونه در تخمین پاسخ قاب های خمشی بتن آرمه

نوع مقاله: علمی - پژوهشی

نویسندگان

1 استادیار، دانشکده فنی و مهندسی، دانشگاه قم، قم، ایران

2 دانشجوی کارشناس ارشد مهندسی سازه، دانشکده فنی و مهندسی، دانشگاه قم، قم، ایران

چکیده

در این مطالعه ارزیابی توانایی پالس معادل تولید شده در تخمین پاسخ قاب‌های خمشی بتن‌آرمه توسط یک مدل‌ ریاضی شبیه‌ساز پالس مورد بررسی قرار گرفته است. با بررسی مدل ریاضی شبیه‌ساز مشخص می‌شود که طیف پاسخ الاستیک پالس‌های شبیه‌سازی شده بوسیله مدل انتخاب شده مطابقت خوبی با طیف پاسخ رکورد واقعی دارد. همچنین تابع مورد استفاده هم به‌صورت کیفی و هم کمی ‌توانایی مدل‌سازی بخش زمان تناوب بالای رکورد واقعی حرکات پالس‌گونه را با دقت بالایی دارد. به منظور ارزیابی پالس معادل حرکات پالس‌گونه در تخمین پاسخ قاب‌های خمشی بتن‌آرمه، پنج قاب بتن‌آرمه 3، 6، 9، 12 و 15 طبقه یکبار تحت رکورد‌های واقعی و بار دیگر تحت پالس‌های معادل متناظر آنالیز شده‌اند. جهت ارزیابی، نتایج برش پایه، حداکثر تغییرمکان نسبی و توزیع تغییرمکان نسبی طبقه در ارتفاع سازه در سه سطح شکل پذیری برای قاب‌ها، تحت رکورد واقعی و پالس معادل آن استخراج شدند. با توجه به نتایج بدست آمده در این تحقیق، پالس معادل حرکات پالس‌گونه در پیش‌بینی پاسخ قاب‌های مورد مطالعه که دوره‌تناوب آن‌ها نزدیک به پالس معادل یا از آن بیش‌تر است، کارایی لازم را داراست. برای حرکات با محتوای فرکانسی بالا این اختلاف زیاد است؛ که با افزایش تعداد طبقات و نزدیک شدن دوره‌تناوب پالس به دوره‌تناوب اصلی سازه و افزیش شکل‌پذیری پیش‌بینی پاسخ سازه دقیق‌تر می‌شود.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Evaluation equivalent pulse of pulse-like ground motion to estimate the response of RC moment-resisting frames

نویسندگان [English]

  • Seyed Rohollah Hosseini Vaez 1
  • Mojtaba Jahan Abadi 2
1 Assistant Professor, Department of Civil Engineering, Faculty of Engineering, University of Qom, Qom, Iran
2 MSc Student in Civil Engineering, Department of Civil Engineering, University of Qom, Qom, Iran
چکیده [English]

In this study the ability of equivalent pulse extracted by a mathematical model from pulse-like ground motion is investigated in order to estimate the response of RC moment-resisting frames. By examining the mathematical model, it is obvious that the model-based elastic response spectra are compatible with the actual pulse-like record. Also, the model simulates the long-period portion of actual pulse-like records by a high level of precision. The results indicate that the model adequately simulates the components of time histories. In order to investigate the ability of equivalent pulse of pulse-like ground motion in estimating the response of RC moment-resisting frames, five frame models including 3, 6, 9, 12 and 15 stories analyzed under actual record and simulated one. The results of the base shear demand, the maximum value of the inter-story drift and the distribution of inter-story drift along the height of the structures in three levels of design ductility is investigated. According to the results of this study, the equivalent pulses can predict accurately the response of regular RC moment-resisting frames when the fundamental period of the structure is equal to or greater than the equivalent pulse of the record. For the ground motion with high-frequency content the difference is high; but with increasing the number of stories and approaching pulse period to the fundamental period of the structure and increasing the level of design ductility of structure, more accurately predict the structural response.

کلیدواژه‌ها [English]

  • Pulse-like Ground Motions
  • Equivalent Pulses
  • Moment Frame
  • Fundamental Period
  • Elastic and Inelastic Response

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