ارتقاء دستگاه آزمایش سه محوری جهت مطالعه رفتار مکانیکی-هیدرولیکی- حرارتی خاکها در دمای بالا

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار، دانشکده مهندسی، دانشگاه آزاد اسلامی واحد همدان، ایران

2 دانشیار، دانشکده مهندسی عمران، دانشگاه علم و صنعت ایران، تهران، ایران

چکیده

امروزه مطالعه رفتار مکانیکی- هیدرولیکی خاکها در دمای بالا مورد توجه محققین رشته ژئومکانیک قرار گرفته است. به خصوص بررسی رفتار موانع رسی و بستر طبیعی موجود در مراکز دفن عمیق ضایعات هسته ای که خاک در معرض دمای تا حدود 120 درجه سانتی گراد قرار می گیرد نیاز به ارتقاء دستگاههای معمول آزمایشهای مکانیک خاک را روزافزون نموده است. این مقاله روند طراحی، ساخت و کالیبراسیون سلول و اجزا دستگاه سه محوری که با نوآوری در حداکثر دمای قابل حصول، برای اولین بار در ایران انجام پذیرفته است مرور می کند. نتایج یک مطالعه بر رفتار مخلوط بنتونیت- ماسه به عنوان مانع مهندسی مرکز دفن، که با این دستگاه انجام شده ارائه گردیده است.

کلیدواژه‌ها


عنوان مقاله [English]

The Improvement of Triaxial Apparatus for Thermo-Hydro-Mechanical Behavior of Soils at Elevated Temperatures

نویسندگان [English]

  • Saed Saeidijam 1
  • Nader Shariatmadari 2
1 Assistant Professor, Hamadan Branch, Islamic Azad University, Hamedan, Iran
2 Associate professor, Department of Civil Engineering Iran University of Science and Technology, Tehran, Iran
چکیده [English]

The need for thermo-hydro-mechanical studies of soils at high temperatures has increased in environmental geomechanics these years. An important case is the behavior of engineering clay barrier or natural host rock in deep nuclear waste repositories that undergo high temperatures up to 120C. Only an apparatus designed for high temperatures can do this kind of studies. This research reviews design, assemble and calibration of a triaxial set that has been made for the first time in Iran. Triaxial tests at high temperatures indicated that sand-bentonite with unit weight in the range of density for engineering barrier of nuclear waste repositories, has contractive behavior. When this mixture was heat up to 110C, both peak and critical state shearing strength reduced about 20 percent and critical state friction angle decreased too. These results were similar to other authors’ results that show the apparatus has worked conveniently

کلیدواژه‌ها [English]

  • Thermo-Hydro-Mechanical Behavior of Soils
  • Triaxial Test Apparatus
  • Elevated Temperature
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