Impact and correlation of rockmass for tunnel excavation through tunnel boring machine - a geo-mechanical classification approach

摘要

Joints are among the most important causes of excessive over break and of trouble with water. They always deserve careful consideration (Karl Terzaghi, 1946). Physical properties of discontinuity generally control the engineering characteristics of a rockmass. Accurate and thorough geological mapping are conducted for design and construction of civil structure. The joint parameters greatly influence stability of an underground structure. This phenomenon has been observed in tunnel driven through tunnel boring machine (TBM). The present paper focuses on the influence on joints for wedge formation and instability of rockmass during excavation through TBM with special reference to the limitation of TBM.