Optimal interval of tunnel with small spacing considering visco-elastic plasticity

Abstract

Based on different surrounding rock classifications, the numerical simulation of visco-elasto-plastic surrounding rock was studied for three roadway tunnels with small spacing, especially analyzing the visco-elasto-plastic effect in the process of rock mass excavation by the step. By the numerical imitation and comparing analysis, the damage characteristic and the deformation law of surrounding rock were given under the same construction method for different surrounding rock classifications of three driveway tunnels, and the deformation law of interval wall and the relationship between the surrounding rock classification and the interval were obtained under the particular construction method for tunnels with small spacing. The minimum interval was selected for engineering design reference under the same excavation way, and a set of reasonable value ranges was given. The reference data and the theoretical basis were provided for the development and construction design of roadway tunnels with small spacing.

Keywords

visco-elastic plasticity / tunnel with small spacing / optimal interval / numerical simulation