关键词: 玄武岩, 裸体斜井井筒, 原岩应力, 集中应力, 围岩稳定

Abstract: The digging of underground laneway will destroy the balanced state of the initial rock stress，making the stress field around laneway redistribute and concentrate.When the concentrated stress is higher than the rock mass strength around laneway，it will cause ground pressure behaviors，for example surrounding rock deformation，loosening，floor heave and so on in laneway.Evidently，the severe degree of ground pressure behaviors is not only relevant to the rock pressure，but also interrelated with the physical and mechanical properties of the rock around laneway.Aiming at the stability of basalt nude inclined shaft surrounding rock of a under-construction mine in Southwest China，based on the knowledge of elasticity and rock mechanics，the comprehensive analysis method of the theoretical analysis and numerical simulation is adopted to analyze the highest concentrated stress of surrounding rock and the relationship between the highest concentrated stress and the approved strength.It is concluded that the highest concentrated stress of surrounding rock is lower than the approved compressive strength of basalt rock mass in the worst condition，the inclined shaft can take the shape of nude laneway，and it provides a scientific theory basis for the field support design and construction.

Key words: Basalts, Nude inclined shaft, Initial rock pressure, Concentrated stress, Stability of surrounding rock