Cable trays mounted in a tunnel typically use what type of mounting?

When cable trays are installed in a tunnel, the typical method of mounting is wall mounting. This approach allows for efficient use of space as the trays can be secured to the tunnel walls, enabling easy access to the cables and avoiding taking up floor space which could be critical for other installations or movement within the tunnel.

Wall mounting also helps in maintaining an organized layout, allowing for a more streamlined and safe installation while minimizing the risk of damage to the cables. Moreover, wall-mounted cable trays can facilitate proper ventilation and avoid potential hazards that could arise from routes that might interfere with vehicle or personnel passage in tunnels.

Other mounting types, such as floor mounting, are less optimal due to space constraints and operational needs in narrow tunnel environments. Ceiling mounting could also be limiting, particularly in tunnels where headroom is a concern. Underground mounting typically refers to installations below ground level, which wouldn't apply to the context of tunnels specifically. Hence, wall mounting is the most suitable choice for this application.