• Title/Summary/Keyword: TBE (Tunnel Boring Extender)

Search Result 1, Processing Time 0.014 seconds

Application of Rotary Cutting Test for Performance Assessment of Tunnel Boring Extender (TBE의 굴착성능 평가를 위한 회전식 절삭시험의 적용)

  • Jeong, Hoyoung;Jeon, Seokwon;Cho, Jung-Woo
    • Tunnel and Underground Space
    • /
    • v.32 no.4
    • /
    • pp.243-253
    • /
    • 2022
  • In this study, the cutting efficiency of TBE (Tunnel Boring Extender) was evaluated by using rotary cutting tester. In the rotary cutting test, a specimen which has a drilled hollow hole at the center was made of rock-like material. The specimen was cut by UDC (undercutting disc cutter) with spiral cutting path to simulate the cutting process of TBE. The cutting forces and specific energy were evaluated under different cutting conditions. The results indicated that the cutter forces of UDC linearly increased with the vertical and radial penetration depths. Among the three directional cutter forces, the normal force is larger than other force components. While the specific energy decreased with the two penetration depths, in particular, it was presumed that the specific energy was minimized at a certain value of the ratio of radial to vertical penetration depth.