关键词: 流变, 西原模型, 中性点, 巷道变形, 锚杆应力分布

Abstract: In order to explore the stress distribution of bolt based on rheological conditions, at first, the visco-elastic plastic displacement solution of circular roadway under the condition of visco-elastoplastic model has been obtained, and then the expressions of bolt shear and axial stress of full-length anchoring bolt have been deduced by using “neutral point” theory. According to the site surrounding rock displacement data, four parameters value in visco-elastoplastic model has been derived reversely. The results show that the position of neutral point has nothing to do with time. When the rock is in the decelerating creep stage, the rate of increasing stress of bolt decreases and reduces to zero gradually. When the rock is in the steady creep stage, the rate of increasing stress of bolt decreases and reduces to a fixed value with the passage of time. This paper has provided a new way to verify whether the bolt is failure or not in roadway service life and to confirm secondary support time.

Key words: rheological, visco-elastoplastic model, neutral point, roadway deformation, stress distribution of bolt