مطالعه‌ی آزمایشگاهی و عددی رفتار باربری و نشست پی‌های دایره‌ای لبه‌دار نسبت به انواع پی‌ها

نوع مقاله : پژوهشی

نویسندگان

1 استادیار گروه عمران، دانشکده‌ی مهندسی، دانشگاه بوعلی‌سینا، همدان.

2 گروه عمران، دانشکده‌ی مهندسی، دانشگاه بوعلی سینا، همدان.

چکیده

پی‌های لبه‌دار در حال گسترش به‌عنوان نوع جدیدی از پی‌ها، جایگزین انواع پی‌های متداول در سازه‌های ساحلی و فراساحلی هستند. مطالعه‌ی عملکرد پی‌های لبه‌دار، با تمرکز بر ارزیابی تأثیر هندسه‌ی پی و مشخصات خاک ضروری است. در این پژوهش، ظرفیت باربری و نشست پی‌های دایره‌ای لبه‌دار واقع بر ماسه، تحت بارگذاری قائم فشاری توسط مدل‌سازی فیزیکی و تحلیل عددی با بررسی تأثیر پارامترهای مختلف شامل عمق لبه، قطر پی، چگالی ماسه و زبری سطوح پی مطالعه شد. عملکرد پی‌های لبه‌دار با سایر انواع پی‌های متداول سطحی، نیمه‌عمیق و سطحی مدفون مقایسه شد. تحلیل نتایج مدل‌سازی‌ها نشان داد که رفتار مدل‌های پی لبه‌دار نسبت به پی‌های سطحی، به‌لحاظ افزایش مقادیر ظرفیت باربری و ضریب واکنش بستر و هم‌چنین کاهش میزان نشست، بهبود قابل‌توجهی داشته‌است. مقادیر بهبود عملکرد پی‌های لبه‌دار با افزایش میزان عمق لبه و زبری سطوح مدل‌ها و هم‌چنین کاهش چگالی نسبی ماسه، افزایش یافت. مقایسه‌ی نتایج ظرفیت باربری پی‌های لبه‌دار با مقادیر متناظر پی‌های نیمه‌عمیق نشان داد که رفتار باربری پی‌های لبه‌دار نزدیک به مقادیر متناظر پی‌های نیمه‌عمیق با عمق و قطر یکسان است. مقایسه‌ی عملکرد پی‌های لبه‌دار نسبت به پی‌های سطحی مدفون، بیانگر کاهش بیشتر میزان نشست پی‌های سطحی به‌علت وجود لبه‌ در زیر پی به‌جای مدفون کردن پی و هم‌چنین بهبود بیشتر ظرفیت باربری با افزایش میزان زبری سطوح لبه است.

کلیدواژه‌ها

عنوان مقاله [English]

Experimental and Numerical Study of Load-Bearing and Settlement Behavior of Circular Skirted foundations Compared to other Types of Foundations

نویسندگان [English]

  • Sajjad Gholipour 1
  • sajjad gholipour 2
1 Civil Engineering Department, Faculty of Engineering, Bu-Ali Sina University, Hamedan, Iran.
2 Civil Engineering Department, Faculty of Engineering, Bu-Ali Sina University, Hamedan, Iran.
چکیده [English]

Skirted foundations are expanding as a new type of alternative foundations for other prevalent foundations in onshore and offshore structures. The study of skirted foundations performance is essential for evaluating the effect of foundation geometry and soil specification. In this research, the bearing capacity and settlement of circular skirted foundations resting on sand under vertical compression loading was studied by physical modeling and numerical analysiswith consideration of the effect of different parameters including skirt depth, foundation diameter, sand density and surface roughness of the foundation models. The performance of skirted foundations was compared with common types of surface, semi-deep and embedded foundations. Analysis of results showed that the behavior of skirted foundation models compared to the surface foundations has been improved significantly in terms of the enhancement in the values of bearing capacity and subgrade reaction modulus, as well as the reduction of settlement amounts. Improvement in the performance of skirted foundations was increased by increasing the skirt depth and surface roughness of models, and also, reducing the density of the sand. The comparison of the bearing capacity results of the skirted foundations with the corresponding values of the semi-deep foundations showed that the load- bearing behavior of the skirted foundations is close to those of semi-deep foundations with the same depth and diameter. Comparison of the skirted foundations performance relative to embedded surface foundations represents a further reduction in the settlement amounts of surface foundations due to the skirt existence underneath foundation instead of its embedment in depth, as well as the further improvement of bearing capacity by increasing the surface roughness of the skirt.

کلیدواژه‌ها [English]

  • Skirted foundation
  • Physical modelling
  • Bearing capacity
  • Semi-deep foundation

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