نمودارهای طراحی برای تخمین پاسخ ساختمان بتنی مجاور گود عمیق پایدار شده به روش میخ‌کوبی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی عمران، دانشگاه خوارزمی، تهران، ایران

2 گروه مهندسی عمران، دانشگاه خوارزمی

چکیده

با توجه به نیاز بیش از پیش به گودبرداری در مناطق شهری، حفظ پایداری و جلوگیری از آسیب به ساختمان‌ها و تأسیسات مجاور، عملیات گودبرداری با استفاده از سیستم‌های پایدارساز جداره‌ گود ضروری است. یکی از روش‌های محبوب جهت پایداری جداره‌های گود، سیستم میخ‌کوبی است. در این روش به منظور بسیج شدن نیروی کششی در المان‌های فولادی، جابه‌جایی دیواره اجتناب‌ناپذیر است. در این پژوهش از تحلیل‌های عددی مبتنی بر روش المان محدود با استفاده از نرم‌افزار MIDAS GTS NX جهت بررسی پاسخ ساختمان بتنی مجاور گود سوده برده شده است. در ادامه، اثر شرایط مختلف ساختمان اسکلت بتنی از جمله تعداد طبقات و فاصله‌ آن از عملیات گودبرداری و گود پایدارشده به روش میخ‌کوبی با عمق‌های مختلف بر وضعیت ساختمان مجاور گود مورد مطالعه قرار گرفته است. نمودارهای ارائه شده در این مقاله، بیانگر میزان نشست فونداسیون، چرخش ساختمان، اضافه تنش محوری به‌وجود آمده در ستون‌های بتنی و کرنش برشی ناشی از گودبرداری در دیوارهای میان‌قابی از جنس مصالح بنایی هستند. این مطالعه نشان داد که اضافه تنش محوری ستون ساختمان مجاور گود در اثر عملیات گودبرداری کمتر از 5 درصد مقاومت فشاری بتن بوده و قابل صرف‌نظر است. بیشترین تغییرمکان در ساختمان‌های مجاور گود به ترتیب در شرایطی رخ می‌دهد که ساختمان در لبه‌ گود و در فاصله‌ای به اندازه‌ عمق گود قرار گرفته باشند. نشست در فاصله‌ای به اندازه‌ دو برابر عمق گود از لبه‌ آن کمتر از 10 درصد نشست حداکثر و در فاصله‌ چهار برابر عمق گود از لبه‎ آن ناچیز است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Design Charts for Estimating Response of R.C. Frame Building Adjacent to Deep Excavation Supported by Soil-Nailing Method

نویسندگان [English]

  • Ali Ghanbari 1
  • S.Alireza Mousavi Moallem 2
1 Department of Civil Engineering, University of Kharazmi, Tehran, Iran
2 Department of Civil Engineering, , Kharazmi University
چکیده [English]

Excavation-induced displacements may cause damage to buildings and urban facilities. The displacement of walls is inevitable in soil nailing method to mobilize the tensile force in steel elements. FEM-based numerical analyses in MIDAS GTS NX were used to evaluate the response of a concrete building adjacent to deep excavation. The effect of various parameters of the concrete frame building, including the number of stories, distance to excavation, and the excavation stabilized by soil nailing at different depths was investigated in the building adjacent to the excavation. The design charts represent the foundation settlement, building rotation, excess axial stress in the concrete columns, and the excavation-induced shear strain in masonry infill walls. According to the results, the presence of a building can cause significant changes in the deformation profile of the ground surface. Results showed the adjacent buildings that are located at the excavation edge and a distance equal to the excavation depth experience the maximum displacement. The excess axial stress in the concrete columns of the building adjacent to the excavation was negligible. Furthermore, with increasing foundation depth, settlement and rotation of the building decreases. This study showed that the axial stress of the building column adjacent to the excavation due to excavation is less than 5% of the compressive strength of concrete. Most displacement in buildings adjacent to the pit occurs when the building is on the edge of the excavation. At a distance of 4 times the depth of the excavation from the edge, the settlement is insignificant.

کلیدواژه‌ها [English]

  • R.C. Frame Building
  • Deep Excavation
  • Soil-Nailing
  • Deformation
  • Midas
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