Relationship between Specifications and Cutting Forces of TBM
Currently, a tunnel boring machine (TBM) is widely used in tunneling. TBM is a full-face machine, therefore the face cannot be observed. This is disadvantageous especially in rapidly changing conditions, as is commonly the case for rock mass in Japan. In previous paper, equations (1) and (2) for estimating rock strength of face with TBM cutting force are proposed based on experimental findings.
σｃ : rock strength p: cutting depth FＮ: thrust force TＲ: torque.
Constants ｃ１ andｃ２ in equations (1) and (2) should be the function of the design parameters of TBM(tunnel diameter, cutter diameter, cutter distance etc.). In this study, the relationship between constants(ｃ１ and ｃ２) and design parameters of TBM was examined for ten tunnels.
It was found that constants ｃ１ was strongly influenced by a cutter diameter d.
n is number of cutter. With increase of a cutter diameter, not only contact area with rock ,but also apparent strength of rock increased.
Constants ｃ２ was also influenced by tunnel diameter and cutter diameter.
By equation (1)〜(4), thrust force and torque of TBM can be estimated if necessary information is available.
Key word： Tunnel Boring Machine，Cutting Force，Rock Strength，Thrust，Torque，Cutter