رفتارنگاری گود پایدارسازی شده به روش ساخت از بالا با استفاده از مطالعات عددی و میدانی (مطالعه موردی)

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد ژئوتکنیک، دانشکده فنی مهندسی، دانشگاه قم.

2 دانشیار، دانشکده فنی مهندسی، دانشگاه قم.

3 عضو هیات علمی گروه عمران، دانشکده فنی مهندسی، دانشگاه قم.

چکیده

تغییرات تنش در اثر حفاری فضاهای زیرزمینی، باعث تغییرشکل زمین اطراف گود می‌شود. بنابراین، چنانچه گودبرداری در مجاورت بافت فرسوده و یا سازه‌های حساس مد نظر باشد، کنترل تغییرشکل زمین با بهره‌گیری از ابزار پایش مناسب، ضروری است. پیش‌بینی روند تغییرشکل‌های زمین نیازمند مدل‌سازی عددی و کالیبراسیون آن با مطالعات میدانی می‌باشد؛ از این‌رو، شناخت دقیق ابزار مورد استفاده و تعیین دقت آن اهمیت زیادی دارد. در این مطالعه، رفتارنگاری و مدل‌سازی عددی یک گود پایدارسازی شده به شیوه ساخت از بالا مد نظر است که در یکی از مناطق پرتردد مرکزی شهر قم قرار دارد. برای این منظور، مراحل ساخت در روش ساخت از بالا به صورت مقطعی مورد پایش قرار گرفته و داده‌های به‌دست آمده از مطالعات میدانی مورد تحلیل قرار می‌گیرد. سپس براساس اطلاعات به‌دست آمده، مدل عددی کالیبره شده و روند تغییرشکل با انجام مطالعات عددی پیش‌بینی می‌‌گردد. بر این اساس، در صورت لزوم طراحی سازه و مراحل اجرا به منظور بهینه‌سازی و یا اقتصادی نمودن طرح، مورد بازبینی قرار می‌گیرد. وجود بافت فرسوده و یک ساختمان پنج طبقه در مجاورت گود، بیانگر اهمیت این مطالعه می‌باشد. مطالعات میدانی با استفاده از دوربین توتال استیشن صورت گرفته است. براساس مطالعات آماری صورت گرفته در این تحقیق، دقت دوربین توتال استیشن در پایش گود مورد مطالعه مقدار مطلوبی جهت کنترل مراحل ساخت و در صورت لزوم اصلاح آن در حین رفتارنگاری می‌باشد؛ با این وجود بر استفاده از ابزار دقیق‌تر در مطالعه گود‌‌های عمیق با خطر زیاد تأکید می‌گردد.

کلیدواژه‌ها


عنوان مقاله [English]

Field monitoring and numerical modeling in an excavation stabilized by Top-Down method (A case study)

نویسندگان [English]

  • Ehsan Ghorbani 1
  • Mahdi Khodaparast 2
  • Abolghasem Moezi 3
1 M.Sc. Student, Department of Civil Engineering, Faculty of Engineering, University of Qom.
2 Associate Professor, Department of Civil Engineering, Faculty of Engineering, University of Qom.
3 Lecturer, Department of Civil Engineering, Faculty of Engineering, University of Qom.
چکیده [English]

Stress changes due to deep excavations will cause ground deformations near the excavated site. Deformation control in the vicinity of worn-out urban textures and important buildings is crucially significant. Prediction of ground deformation trends needs numerical modeling which should be calibrated with field studies; therefore, the accuracy of monitoring tool should be investigated in the field precisely. In this study, field monitoring and numerical modeling of an excavation stabilized by Top-Down method using total station in an overcrowded street in the city of Qom in Iran is implemented. In this project, construction sequences in Top-down excavation are monitored and the obtained data are analyzed frequently. Depending on the evolved information and the calibrated model, designation or construction stages in stabilization could be reconsidered to secure the excavation or to enhance the economy of the project. The quality of the gathered data in this method is of high importance which should be evaluated using statistical analysis to determine the precision of the monitoring tool. According to the conducted statistical analysis, the accuracy of Total Station in this study is appropriate for monitoring and construction technique in this project. However, using more accurate tools in monitoring high-risk excavations is emphasized.

کلیدواژه‌ها [English]

  • Field monitoring
  • Total Station
  • Top-Down excavation
  • Accuracy control
  • Finite element model

 

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