تأثیر کنج محدب بر جابه‏جایی دیواره‌های گودبرداری مهار شده: تحلیل سه‌بُعدی

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشکده مهندسی عمران، دانشگاه یزد، یزد، ایران

چکیده

در پروژه‏های گودبرداری، وجود کنج‏های محدب باعث می‏شود تحلیل‌های دو بُعدی دقیق نباشند. این پژوهش، به بررسی تأثیر این کنج‏ها بر تغییرشکل دیواره‏های مهار شده، با استفاده از  مدل‏سازی سه‌بُعدی می‌پردازد. در واقع، پژوهش حاضر با استفاده از نرم‌افزار FLAC3D به مدل‏سازی عددی دوبعدی و سه‌بعدی اثر کنج‌های محدب بر تغییرشکل‌های ناشی از گودبرداری برای دیواره‌های پایدارسازی شده با روش میل‌مهار می‌پردازد. همچنین، تأثیر پارامترهایی نظیر نوع خاک، چسبندگی و ضریب اطمینان طراحی هدف (Target Design FOS) بر تغییرشکل‌ها و ضریب اطمینان پایداری نهایی (Final Stability FOS) در کنج محدب مورد بررسی قرار گرفته است. نتایج مطالعه حاضر نشان می‌دهد که طول ناحیه تحت‌ تأثیر کنج (ناحیه‌ای از اطراف کنج محدب که در آن مقادیر نسبت جابه‌جایی سه‌بعدی در محل تاج گود بزرگتر از مقدار متناظر دوبعدی است) با کاهش مقاومت خاک کاهش پیدا می‌کند، به‌طوری‌ که در خاک ضعیف، متوسط و قوی به ترتیب H2، H5/1 و H25/1 است. به علت تأثیر هندسه سه‌بعدی کنج محدب، مقادیر ضریب اطمینان سه‌بعدی کمتر از مقادیر متناظر دوبعدی هستند. 

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of Convex Corners on Displacement of Restrained Excavation Walls: A Three-Dimensional Analysis

نویسندگان [English]

  • Mahsa Mokhtari Dehaghani,
  • Maryam Mokhtari
  • mohammad hazeghian,
Faculty of Civil Engineering, Yazd University, Yazd, Iran
چکیده [English]

In excavation projects, presence of convex corners makes 2D analyses inaccurate. This study investigates the effect of these corners on deformation of retaining walls using 3D modeling. The present study uses FLAC3D software for two-dimensional and three-dimensional numerical modeling to study the effect of convex corners on the deformations caused by excavation for walls stabilized by anchor rod method. It also examines the effect of various parameters such as soil type, soil adhesion, pit height and reliability coefficient on the deformation rate of convex corner. Results of the present study show that the length of corner-affected area (area around the convex corner where values of the three-dimensional displacement ratio at the location of crown pit is greater than the two-dimensional corresponding value) decreases with the decrease in soil resistance. So, in weak, medium and strong soil, it is 2H, 1.5H and 1.25H respectively. Due to the influence of three-dimensional geometry of convex corner, the three-dimensional reliability coefficient values are lower than corresponding two-dimensional values.

کلیدواژه‌ها [English]

  • Retaining structure؛
  • Anchor rod؛ Convex corner؛ Three-Dimensional Numerical Analysis؛ FLAC3D Software
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