Impact Analysis and Optimization of Key Material Parameters of Embedded Water-Stop in Tunnels

Abstract

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.

Keywords

• tunnel engineering
• water-stop
• tunnel joints
• epoxy−quartz sand coating
• adhesion