As shown in Fig. 7(a), it can be seen that, when accounting for the effect of tunnel face advancement in the Kelvin-Voigt rock, the initial slope of uN at t = 0 is not only proportional to the stiffness ratio Gm/Gk, but also relates to the term vαtd/RL. Additionally, the normalized displacements uN are temporarily affected by tunnel face advancement,while this effect will gradually disappear due to the radial stress releaseof the surrounding rock. Finally, regardless of consideration of the effect of tunnel face advancement or not, the ultimate uN of the KelvinVoigt rock will eventually converge to 1 + Gm/Gk.