Abstract:The experiment is based on the Qinghuabian Tunnel which is a newly-built coal transportation railway from Mengxi to central China. The deformation of strata and the stress test elements of surrounding rock are embedded, and the variation of mechanical properties of strata and surrounding rocks of long-span shallow tunnels in loess area during excavation is studied. The results show that the dome settlement deformation and horizontal convergence deformation caused by construction are composed of two parts: uniform deformation stage and stable stage, The vertical settlement of strata increases at first and then decreases with the increase of buried depth; when the working surface is stable, the advance influence distance of the horizontal displacement of the tunnel cross section is about 8m, and the advance influence distance of the horizontal displacement of the axial direction is about 15m. When observing the lag of the section and advance excavation surface, the cross section direction and axial direction horizontal displacements of the soil around the tunnel develop toward the inside of the tunnel and away from the tunnel respectively; After the initial branch is completed, the lining stress is readjusted, the pressure on the left and right arches is not increasing, and the pressure on the invert is continuing to increase. The conclusions can provide reference for the design and construction of shallow-buried subsurface-excavating long-span tunnels in the loess area.