مهندسی سازه و ساخت

مهندسی سازه و ساخت

پاسخ دینامیکی شالوده‌های مربعی صلب بر روی نیم فضای الاستیک تحت امواج مایل SH با روش المان مرزی

نوع مقاله : علمی - پژوهشی

نویسندگان
1 دانشجوی دکتری، دانشکده مهندسی عمران، دانشگاه ارومیه، ارومیه، ایران
2 استادیار گروه مهندسی عمران، دانشکده مهندسی عمران، دانشگاه ارومیه، ارومیه، ایران
چکیده
در این مقاله پاسخ دینامیکی یک شالوده مربعی صلب بر روی یک نیم فضای الاستیک مورد بررسی قرار گرفت. بمنظور در نظر گرفتن اندرکنش سینماتیکی خاک و سازه، لازم است شالوده بدون جرم فرض شود. در این تحقیق شالوده مربعی صلب در معرض امواج هارمونیک و مایل SH در نظر گرفته شد. با در نظر گرفتن ویژگی‌های موج از جمله مایلیت موج ورودی که با دو پارامتر شامل زاویه ورودی موج با راستای قائم و همجنین زاویه برخورد موج نسبت به ابعاد شالوده در پلان توصیف می‌شود، تجزیه و تحلیل اثر اندرکنش سینماتیکی خاک و شالوده مورد مطالعه قرار گرفت. بدین‌ترتیب ابتدا توابع امپدانس و سپس حرکت ورودی به شالوده شامل حرکات افقی و پیچشی شالوده محاسبه گردید. بمنظور تجزیه و تحلیل دینامیکی شالوده از روش المان مرزی استفاده شد. بدین‌منظور ناسرگی ضعیف و قوی موجود در معادلات انتگرالی حاکم مورد بررسی قرار گرفت. نتایج نشان داد که تغییرات زاویه قائم و افقی موج ورودی تأثیر مهمی بر پاسخ دینامیکی شالوده داشته و بطور خاص، امواج غیر قائم باعث کاهش حرکت انتقالی نسبت به حرکت میدان آزاد و نیز ایجاد پیچش اضافی در شالوده می‌گردد. نتایج بدست‌ آمده در قالب توابع امپدانس و نیز جابجایی افقی و پیچشی شالوده در برابر فرکانس بی‌بعد بیان شدند. همچنین در حالات ساده، یافته‌های حاصل با نتایج موجود در ادبیات فنی مقایسه شدند و تطابق قابل‌قبولی مشاهده گردید.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Dynamic Response of Rigid Square Foundations on an Elastic Half-Space Subjected to Oblique Incident SH Waves Using Boundary Element Method

نویسندگان English

Foroughّ Ashkan 1
Abbas Eslami Haghighat 2
1 Ph.D. student,, civil engineering department, Urmia university, Urmia,, Iran
2 assistant professor, civil engineering department, Urmia university, Urmia,, Iran
چکیده English

In this paper, the dynamic response of a rigid square foundation on an elastic half-space was investigated. In order to consider the kinematic soil structure interaction, massless foundation is assumed. In this research, a rigid square foundation was subjected to oblique incident harmonic SH waves. Taking into account the characteristics of the wave, including the obliquity of the wave, which is described by two parameters including the angle of incident wave with the vertical direction and the angle of impact of the wave with the foundation edge in the plan, the analysis of the effect of the soil foundation kinematic interaction was studied. The impedance functions as well as the foundation input motion including the torsional and horizontal motions of the foundation were then calculated. Boundary element method was used for the dynamic analysis of the foundation. The weak and strong singularity in governing integral equations were investigated. The results showed that changes in the vertical and horizontal angle of the incident wave have an important effects on the dynamic foundation response, and in particular, non-vertical waves reduce the translational motion compared to free field motion and also cause additional torsional motion in the foundation. The obtained results were expressed in terms of impedance functions as well as horizontal and torsional motions of the foundation versus the dimensionless frequency. Also, in simple cases, the results were compared with the results in literature and an acceptable agreement was observed. The results show the vertical and horizontal angles of incident waves can influence the foundation response. As vertical angle increases, the foundation response becomes further away from the free field response, and at higher frequencies, its value decreases and approaches to zero. With the increase of the horizontal angle, the horizontal displacement also decreased. The results are shown in dimensionless frequency graphs.

کلیدواژه‌ها English

Impedance Functions
Oblique Incident SH Wave
Rigid Square Foundation
Kinematic Soil Structure Interaction
Boundary Element Method
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  • تاریخ دریافت 13 شهریور 1402
  • تاریخ بازنگری 27 آبان 1402
  • تاریخ پذیرش 28 دی 1402