青云翻译

Hi mouth pool tunnel split tunnel, in the design of Portal using the side wall Portal, in order to achieve the stability requirements

Pool tunnel separate tunnels, in the design of this portal end-wall cave in order to meet the requirements of the stability

The happy mouth pond tunnel is the separation formula tunnel, the portal uses the end wall type portal in this design, meets the stable requirements

Hi port pool tunnels for split tunnel, in this design-in-a-wall-to-door, reach the requirements of stability

Pool tunnel separate tunnels, in the design of this portal end-wall cave in order to meet the requirements of the stability