مطالعه آزمایشگاهی و عددی رفتار پی دامنه دار واقع بر لوله مدفون تحت بارگذاری محوری استاتیکی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی عمران، واحد نجف آباد، دانشگاه آزاد اسلامی، نجف آباد، ایران

2 دانشکده مهندسی عمران و محیط زیست، دانشگاه بوخوم، بوخوم، آلمان

چکیده

ظرفیت باربری و نشست پی‌های سطحی واقع بر لوله معمولا در خاک‌های ماسه‌ای به میزان قابل قبولی نبوده است، از این رو به منظور بهبود عملکرد این گونه پی‌ها روش‌های مختلفی پیشنهاد می‌گردد که یکی از به صرفه‌ترین روش‌ها اضافه نمودن دامنه به لبه‌های پی سطحی است. استفاده از دامنه زیر محیط پی‌های سطحی، سبب افزایش عمق مؤثر پی و محصورسازی خاک درون دامنه شده، که بارهای سازه به اعماق مقاوم زیرین در تراز نوک دامنه انتقال می‌یابد. در سال‌های اخیر ارزیابی عملکرد پی‌های دامنه دار به عنوان یکی از موضوع‌های مطلوب مهندسین عمران تبدیل شده است. در این مقاله اثر عمق مدفون و فاصله لوله مدفون تا مرکز بارگذاری پی با استفاده از آزمایش‌های ازمایشگاهی و عددی مورد ارزیابی قرار گرفته است. از این رو از پی دامنه دار واقع بر لوله مدفون با دامنه‌های B و2B  (B عرض پی) استفاده شده است. نتایج آزمایش‌های آزمایشگاهی نشان می‌دهد که با بهره بردن از پی دامنه دار با عمق 2B می‌توان ظرفیت باربری را در مقایسه با پی نواری بیش از 300% افزایش داد. مقایسه عددی پی دامنه دار با پی نیمه عمیق و نواری مدفون نشان می‌دهد که ظرفیت باربری پی دامنه دار کمتر از 10% با پی نیمه عمیق اختلاف داشته است، که با بهره‌گیری از پی دامنه دار می‌توان مهندسین عمران را به سمت طراحی‌های اقتصادی و دقیق‌تر سوق داد.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Laboratory and Numerical Study of the Behavior of Skirted Foundation Located on a Buried Pipe under Static Axial Loading

نویسندگان [English]

  • Moein Mohammadizadeh 1
  • Bahram Nadi 1
  • alborz HAJIANNIA 1
  • Elham Mahmoudi 2
1 Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
2 Department of Civil and Environmental Engineering, Ruhr-Universität Bochum, Bochum, Germany
چکیده [English]

The bearing capacity and settlement of shallow foundations located on the pipe are usually not acceptable in sandy soils. Therefore, in order to improve the performance of strip foundations, various methods are proposed, as a cost-effective alternative is to add skirts to the edges of the shallow foundation. the addition of the skirt to the edges of the shallow foundation increases the effective depth of the foundation and soil trapped within the skirts, and loads of the structure are transferred to the bottom depth at the level of the skirt tip. In recent years, performance assessment of skirted foundations has become one of the desired topics for civil engineers. In this article, the effect of the burial depth and horizontal distance from the center of the pipe to a single load have been evaluated using numerical and experimental tests. Therefore, the skirted foundations located on the buried pipe with skirts B and 2B (B is the width of the foundation) have been used. The results of the laboratory tests show that by using the skirted foundation with skirts of 2B, the bearing capacity can be increased by more than 300% compared to the strip foundation. A numerical comparison of the skirted foundation with semi-deep and embedded strip foundation shows that the bearing capacity of the skirted foundation was less than 10% different from the semi-deep foundation. Civil engineers can be led towards more economical and accurate designs by using the skirted foundation.

کلیدواژه‌ها [English]

  • Skirted foundation
  • Finite element limit analysis (FELA)
  • Buried pipe
  • Laboratory model
  • Sand

مراجع

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نشریه مهندسی عمران امیرکبیر
دوره 55، شماره 1
فروردین 1402
صفحه 3-18

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