Asymmetric Deformation Mechanism and Control of Roadway in Structural Complex Area

Abstract

In view of asymmetric deformation of a roadway in structural complex area, in situ investigation, theoretical analysis, numerical simulation and industrial test were carried out to deeply research the mechanism of asymmetric deformation and control method. Results show that large and unsymmetrical deformation with differential distribution along the axial direction of the roadway is the deformation characteristic of its surrounding rock. Also, complex ground stress, easily weakened rock properties, asymmetric rock structure and uniform supporting structure are primary reasons that the roadway is asymmetrically deformed, whose key regions are upper sidewall corner and lower sidewall shoulder of the roadway. On this basis, an asymmetrically-control strategy is proposed, which includes homogenizing the surrounding rock, strengthening rock masses and coupled supporting of key regions, along with the control method. Industrial test result shows that the roadway has been in a stable deformation stage after repairation within about 20 days, with the deformation of surrounding rock well controlled within 100 mm, and asymmetric deformation has also been effectively controlled. This study can be used as a reference for the control of asymmetric and large deformation of roadway in other similar complex conditions.