مطالعه‌ی تاثیر وزن و هندسه‌ی ساختمان بر نشست سطح زمین ناشی از تونلسازی مرحله‌ای با استفاده از روش عددی اجزای محدود

نوع مقاله: مقاله پژوهشی

نویسندگان

1 کارشناس ارشد مکانیک سنگ؛ گروه معدن؛ دانشکده‌ی فنی و مهندسی؛ دانشگاه لرستان

2 دانشیار؛ دانشکده‌ی مهندسی معدن و متالورژی؛ دانشگاه صنعتی امیرکبیر

چکیده

با توجه به مشکلات ترافیکی شهرهای بزرگ، نیاز به ساخت تونل‌های شهری اجتناب‌ناپذیر است. حفر تونل سبب تغییر میدان تنش برجا شده و یک ناحیه‌ی تغییر مکان در محدوده‌ی اطراف تونل بوجود می‌آورد. در این خصوص نه تنها ساختمان‌های مجاور تحت تاثیر حفاری تونل قرار می‌گیرند؛ بلکه میدان تنش و تغییر مکان حاصله، متاثر از مشخصات ساختمان‌های مجاور خواهد بود. این موضوع یکی از جنبه‌های مهم تونلسازی محیط شهری است. بنابراین لازم است پیش از مرحله‌ی ساخت، پارامترهای موثر بر این رابطه‌ی متقابل بررسی شود. در این پژوهش فاکتورهای اصلی ساختمان نظیر وزن، عرض و طول آن، با استفاده از روش اجزا محدود بصورت سه‌بعدی شبیه‌سازی شده است. نتایج نشان می‌دهد، حضور ساختمان‌های سطحی اثرات دوگانه‌ای بر گودی نشست سطح زمین دارند. افزایش وزن ساختمان موجب افزایش نشست سطح زمین شده و از طرفی، صرف نظر از وزن ساختمان، بواسطه‌ی وجود پی ساختمان و صلبیت ناشی از آن، که موجب بهبود شرایط زمین می‌شود، نشست در سطح زمین نسبت به شرایط بدون وجود ساختمان،کاهش می‌یابد. افزایش عرض ساختمان منجر به کاهش نشست در سطح زمین شده و افزایش طول ساختمان، نشست در سطح زمین را افزایش می‌دهد. هر چند عرض ساختمان فاکتور موثرتری نسبت به طول ساختمان در مهار رفتار متقابل ساختمان-تونل است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Study of the Effects of Building Weight and Geometry on the Surface Settlement due to Sequential Excavation Using Numerical Finite Element Approach

نویسندگان [English]

  • Farshad Kolivand 1
  • Mostafa Sharifzadeh 2
1 M.Sc. in Rock Mechanics; Mining Faculty; Department of Engineering; Lorestan University
2 Associate Professor; Department of Mining and Metallurgical Engineering; Amirkabir University of Technology
چکیده [English]

Considering traffic congestion in mega cities, the need to construct urban tunnels is inevitable. The reciprocal effect of tunneling-induced ground settlement and surface buildings is an important factor during shallow tunneling design procedures in urban areas. Hence, the effective factors in this reciprocal relationship need to be appraised prior to the construction phase. In this paper, the major characteristics of buildings have been numerically simulated using 3D finite element approach. It has been demonstrated that weight and length of buildings have shown parallel correlation with surface settlements. However, building width have had reverse trend with surface settlements.
 
Introduction
The main purpose of this research is the study of influence of building weight and geometry on the surface settlement due to sequential excavation method, and interaction between the building and tunnel. It has been investigated by simulating systematic construction process of the tunnel using finite element numerical method.
 
Methodology and Approaches
In this paper, the major characteristics of buildings have been numerically simulated using 3D finite element method. In addition, the results of study on the field data of the Nyayesh tunnel are presented.
 
Results and Conclusions
The results have proved that the existence of surface buildings has reciprocal effects on ground settlement troughs. The increase of the building weight will result in increase of surface settlements. On the contrary, by ignoring building weight, presence of surface building foundations will cause a less settlement compared to the green field condition which is due to increase of the rigidity of building foundation and thereby ground improvement. The increase of building width reduces the surface settlements, and the increase of the building length leads to more surface settlement, although the building width is a more effective parameter, which controls the overall tunneling-building interaction behavior than the building length. Thus, building weight and geometry effectively influence the surface settlements troughs in urban tunneling.

کلیدواژه‌ها [English]

  • Sequential excavation
  • Sadr-Nyayesh tunnels
  • Finite element
  • Building-tunnel interaction
  • Surface settlement
  • Building weight
  • Building geometry
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