Abstract: Ground loss is an important factor in the calculation of soil deformation caused by shield tunnel excavation. In line with the limit equilibrium principle, the distribution of ground loss in Loganathan’s formula was revised using a uniform ground movement model. A refined analytic solution was derived and expanded to three-dimensional space. As shown by case analysis, the present solution obtains smaller width of surface settlement troughs and horizontal displacements of soil compared with Loganathan’s formula. The results of the refined solution are more consistent with field observations.

Key words: shield tunnel, soil deformation, ground loss, refined analytic solution, Loganathan’s formula