Study on Longitudinal Deformation Analysis and Support Technology of Surrounding Rock in Roadway Excavation

Abstract

To study the influence of excavation space effect on roadway excavation, Hoek’s displacement coefficient equation is used to describe the longitudinal deformation law of roadway surrounding rock under the spatial effect, and the relationship between the radial displacement of the roadway and the virtual support force in the mechanical model is established. The mathematical model derives the relationship between the virtual support force and the distance from the excavation face under the spatial effect of the excavation face. Based on the Mohr-Coulomb strength criterion, the mathematical expressions of surrounding rock stress, plastic zone radius and excavation distance during roadway excavation are derived. According to the variation of the longitudinal displacement of the surrounding rock of the roadway and the radius of the plastic zone, the support design of the roadway can be better. The results show that taking roadway excavation face as an example, compared with the FLAC3D simulation analysis, the displacement of the surrounding rock at the excavation face is about 31%, and the space effect of the excavation face is used to support the roadway in time. Protection can effectively control the deformation of the roadway in the early stage and slow down the development of the surrounding plastic zone of the roadway.

Keywords

• excavation face
• spatial effect
• surrounding rock displacement
• vertical deformation
• support technology