Shear Properties of Internal Support System (Rock Bridges)

  • سال انتشار: 1388
  • محل انتشار: هشتمین کنگره بین المللی مهندسی عمران
  • کد COI اختصاصی: ICCE08_432
  • زبان مقاله: انگلیسی
  • تعداد مشاهده: 2011
دانلود فایل این مقاله

نویسندگان

A. Ghazvinian

Academic Member, Rock Mechanics Division, Tarbiat Modares University, Tehran, Iran

V. Sarfarazi

Research Scholar, Rock Mechanics Division, Tarbiat Modares University, Tehran, Iran

M. R. Nikudel

Academic Member, Geology Department, Tarbiat Modares University, Tehran, Iran

چکیده

Presence of rock bridges in rock masses would increase the bearing capacity of Non-persistent discontinuities. This increase is because of the cohesion and friction angle of the internal support system rendered by the rock bridges. In this article the effect of the area and configuration of the rock bridges on their shear properties are investigated. A total of 36 various models with dimensions of 30 cm× 30 cm× 30 cm of plaster specimens were fabricated simulating the open joints possessing 1 rock bridge. The introduced rock bridges have various continuities in shear surface. The area of the rock bridge was 300 cm2, 450 cm2, 600 cm2 out of the total fixed area of 900 cm2 respectively. The fabricated specimens were subjected to shear tests under 4 different normal loads (20, 30, 40 and 50 kg/cm2) in order to investigate the shear parameters. The results indicated that the failure pattern and the failure mechanism were affected by two parameters; i.e. the continuity of the rock bridge and the normal loads. So that increasing in the effective joint in front of the rock bridge changes the shear failure mode to tensile failure mode. Also shear failure occurs in the rock bridge at high normal loads. Furthermore, the cohesion strength decreases with the increasing of the effective joint in front of the rock bridges (in fixed area of rock bridges) while the friction angle was behaved constant all through the tests carried out for various models.

کلیدواژه ها

Rock bridges, cohesion, friction angle, shear and tensile failure mode.

مقالات مرتبط جدید

اطلاعات بیشتر در مورد COI

COI مخفف عبارت CIVILICA Object Identifier به معنی شناسه سیویلیکا برای اسناد است. COI کدی است که مطابق محل انتشار، به مقالات کنفرانسها و ژورنالهای داخل کشور به هنگام نمایه سازی بر روی پایگاه استنادی سیویلیکا اختصاص می یابد.

کد COI به مفهوم کد ملی اسناد نمایه شده در سیویلیکا است و کدی یکتا و ثابت است و به همین دلیل همواره قابلیت استناد و پیگیری دارد.