Tired of the same old topics of conversation when you get together with family and friends? Next time, why not impress them with your newly acquired knowledge of how the vivaNext subway extensions will be constructed?

Surprisingly, few people know that there are many different elements to consider when building a subway, including which construction technique to use. As it turns out, that mostly depends on where one is digging.

Now for the boring stuff. Tunnel boring, that is. It’s one of the two main techniques used to build a subway. The second one is cut-and-cover.

The tunnel boring technique is generally used for deeper applications such as between stations. Because the tunnels are literally bored out below the surface, there is no disruption at the ground level except at the entry and exit points of the machinery.

Cut-and-cover, on the other hand, is the technique generally used for shallow applications such as station locations. In this case, there is some disruption at the ground level and temporary decking is installed when necessary to accommodate vehicular and pedestrian traffic.

In addition to tunnels and stations, the construction of a subway involves building a number of other special structures located above and below ground. These include crossovers, triple track structures, tail tracks, electrical substations, emergency exit buildings, vent shafts, bus and commuter rail terminals, parking lots, passenger pick-up and drop-off facilities, and pedestrian entrances.