 To study the stress distribution characteristics of surrounding rock and the spalling mechanism of deep hard rock tunnels with different arch heights, the complex variable function and angle-preserving transformation method in elasticity theory was applied to the analytical solution of tangential stress distribution of arch tunnels during stress adjustment. Additionally, true triaxial tests were conducted on granite cube specimens, 100 mm x 100 mm x 100 mm, containing holes with three arch heights, including the 25 mm semicircular arch, 16.7 mm 3-centered arch, and 12.5 mm 3-centered arch, to simulate the spalling process under different initial ground stresses. The stress distribution solution and experimental results showed that the initial failure stress of arch holes is 0.39 to 0.48 times the uniaxial compressive strength, UCS, of the rock. The initial failure location occurs at the arch foot, where tangential stress maximizes. When the lateral pressure coefficient is in the range of 0.38 to 0.50, the tangential stress is 3.2 to 3.5 times the u. This article is authored by ComPang, GuaQing Yi, Song Luo, and others. We are article.tv, links in the description below.