Tunnel excavation method

The invention relates to the technical field of tunnel construction, in particular to a tunnel excavation method. The tunnel excavation method comprises the steps that the rock mass strength of a tunnel face is detected; value and direction of ground stress in front of the tunnel face are monitored, so that an occurrence condition and an occurrence position of rockburst are pre-judged; drilling iscarried out on the tunnel face to form pre-drilled holes, and the pre-drilled holes are located at an excavation contour line of the tunnel face; the pre-drilled holes are filled with explosives, andlocal blasting is carried out on the pre-drilled holes, so that a plurality of cracks extending out of the excavation contour line are formed around the pre-drilled holes; water is injected into thepre-drilled holes, and the water injection pressure is adjusted according to the surrounding rock strength of the tunnel face, so that water enters the cracks and the cracks are enlarged; and a section of tunnel is excavated fo