Abstract
The Haba Snow Mountain Tunnel experienced severe deformation caused by foliated metamorphic basalt. This rock has high metamorphism, easy weathering, and low strength. This study examines the rock's microscopic characteristics and mechanical properties to understand its impact on tunnel stability and offer guidance for similar engineering challenges. Through comprehensive analysis of the rock's composition and structure, combined with mechanical strength testing, the study establishes strong correlations among uniaxial compressive strength, rebound strength, and point load strength. Key findings reveal that the point load index correlates linearly with uniaxial compressive strength (y = 10.97x, R²=0.93). These results not only enhance the understanding of foliated metamorphic basalt's properties but also offer practical recommendations for optimizing strength testing methods. This study provides crucial technical references for tunnel design under similar geological conditions.