Leakage diseases frequently occur in mountain tunnels, and the lining joints are weak waterproof links. In order to solve the problems such as insufficient waterproof technology for existing tunnel joints, this paper relies on the scientific and technological project of the Hubei Provincial Department of Transportation to optimize the key parameters of the tunnel water-stop material and uses numerical simulation methods to analyze the impact of the hardness of the water-stop and the bond strength between the water-stop and concrete on its deformation and waterproof ability. Through the adhesion test, the optimization method of the bond strength between the water-stop and concrete is explored. The results show that: (1) the deformation stress of the water-stop will increase with the increase in hardness and reducing the hardness of the water-stop can improve its stress deformation state. Considering that low hardness increases the risk of damage and reduces the quality, it is recommended that the hardness be 55–60 (HA). (2) The adhesion between the water-stop and the concrete lining is the key to waterproofing the water-stop. Increasing the adhesion between the water-stop and the concrete is an effective optimization method. However, to prevent excessive deformation stress, it is necessary to optimize the geometric structure of the water-stop simultaneously. (3) Placing an epoxy–quartz sand coating on the surface of the water-stop can increase the adhesive force between the water-stop and the concrete. When the thickness of the epoxy layer is 2 mm, and the particle size of quartz sand is 26–40 mesh, the effect is best.

Foot steel pipe was the main arch foot supporting structure to control large deformation of loess tunnels, but the supporting effect was not ideal. Taking Yulinzi Tunnel in Qingyang, Gansu Province, as the engineering background, the design concept and implementation scheme of a foot steel pipe active bearing was put forward. The purpose was to solve the problem that it was difficult to control the surrounding rock settlement with the foot steel pipe. Numerical simulation and field experiments were used to verify the effect of the active bearing technology of the foot steel pipe. The main conclusions were as follows: (1) The effect of increasing the diameter of the foot steel pipe is better than that of increasing the number of foot steel pipes. (2) The active bearing mode of exerting its bearing capacity in advance by prepressing the foot steel pipe can effectively reduce the settlement of the vault. The settlement rate of the vault can be reduced by about 70% in 1–2 days and more than 50% in 1–3 days. (3) At the initial stage of surrounding rock deformation, this technology can provide a large bearing capacity, thereby reducing the overall deformation of the surrounding rock, slowing down the release of the surrounding rock pressure, and playing a positive role in the settlement control of the vault.