مدلسازی عددی و اعتبار سنجی آزمایشگاهی در تعیین چقرمگی مود بازشونده ترک در بتن با استفاده از آزمایش دیسک برزیلی درزه دار

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی عمران، دانشگاه صنعتی شریف، تهران، ایران

2 دانشکده مهندسی معدن، دانشگاه صنعتی همدان، همدان، ایران

3 استاد، دانشکده مهندسی عمران، دانشگاه صنعتی شریف

4 دانشکده مهندسی معدن، دانشگاه ازاد اسلامی واحد بافق، بافق، ایران

چکیده

در این مقاله با استفاده از کد جریان ذره دو بعدی و تست های آزمایشگاهی چقرمگی مود بازشونده ترک در بتن توسط آزمایش دیسک برزیلی درزه دار تعیین و نتایج مدلسازی و یافته های آزمایشگاهی مقایسه شدند. به این منظور دو نمونه دیسکی بتنی به قطر mm 54 و ضخامت mm 27 آماده شد. این نمونه دارای یک درزه مرکزی به طول mm 20 و بازشدگی mm 1 است. نمونه ها از ترکیب آب، شن ریزدانه و سیمان با نسبت 1-5/0-1ساخته می شود. نمونه دیسکی شکل تحت بارمحوری قرار می گیرد. شبیه سازی عددی توسط کد جریان ذره دوبعدی نیز برای اعتبار سنجی نتایج آزمایشگاهی انجام شد. نتایج نشان می دهد که ترک از نوک درزه ایجاد شده و به موازات بارگذاری رشد کرده و به لبه نمونه متصل می شود. این الگوی رشد ترک در تطابق خوبی با نتایج آزمایشگاهی است. چقرمگی شکست بدست آمده از دو روش آزمایشگاهی و عددی نیز با یکدیگر مشابه هستند.

کلیدواژه‌ها


عنوان مقاله [English]

Numerical and Experimental Investigation for Determining the Opening Mode Toughness of Concrete Using Cracked Brazilian Disk Test

نویسندگان [English]

  • Hadi Haeri 1
  • Vahab Sarfarazi 2
  • Alireza Khaloo 3
  • Mohsen Farazmand 4
1 Department of Civil Engineering, Sharif University of Technology, Tehran, Iran
2 Department of Mining Engineering, Hamedan University of Technology, Hamedan, Iran
3 Distinguished Professor, Department of Civil Engineering, Sharif University of Technology, Tehran, Iran
4 Department of Mining Engineering, Bafgh Branch, Islamic Azad University, Bafgh, Iran
چکیده [English]

In this paper, a simultaneous experimental and numerical analysis of opening mode toughness in The Pre-joined Brazilian disc using Brazilian tests are carried out. These numerical results are compared with the existing experimental results. For this purpose, two concrete disc specimens of 54 mm diameter and 27 mm thick were prepared. These specimens have a central joint of 20 mm in length and an opening in mm 1. Specimens are made from a mixture of water, fine sand, and cement with a ratio of 1-5 / 0-1. The same specimens are numerically simulated by a two-dimensional particle flow code (PFC).The results indicate that the crack formed from the tip of the joint and grows parallel to the load and connects to the edge of the specimen. The Fracture toughness obtained from the numerical method is in good agreement with experimental results.

کلیدواژه‌ها [English]

  • Opening-Mode Fracture Toughness
  • Pre-Cracked Brazilian disk
  • Code Particle Flow (PFC)
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