When people think of tunnels, they mostly conjure a mountainous terrain where the road goes through a mountain or hill. Since Florida is mostly flat and at sea level, Florida is more known for its bridges over waterways. With advancements in technology, however, tunnel-digging has become more widespread, with the possibility of seeing more tunnel projects in the State of Florida. In this article, we will give a brief overview of tunnel construction and how experts build tunnels all over the world.
What is a Tunnel?
Tunnels are passages that allow access either through a surface or underneath it. A tunnel might exist to allow car passage, railway passage, or even boat passage. Subway systems are an example of passenger rail service that operates and connects through a series of tunnels.
Does Florida Have Any Tunnels?
Currently, Florida is known for three tunnels:
- The Walt Disney World Utility Tunnel System
- The Henry E. Kinney Tunnel, a.k.a. The New River Tunnel in Fort Lauderdale
- The Port of Miami Tunnel
What Are Tunnel Construction Methods?
There are multiple methods for tunnel construction. Depending on the geography and geology of the proposed area for the tunnel, some methods might be more suitable than others. The common methods for tunnel construction are as follows:
- Cut and cover method
- Bored tunnel method
- Clay kicking method
- Shaft method
- Pipe jacking method
- Box jacking method
Cut and Cover Method
Paving experts use the cut and cover method to build tunnels at a shallow depth. This is how workers build most subway systems. They start by making a trench into the ground. Then, they install support walls, which are strong enough to hold a bearing load. Finally, they install the roof, which allows for further excavation of the tunnel.
Bored Tunnel Method
The bored tunnel method is a modern method that is very expensive but one of the quickest methods in tunnel construction. The bored tunnel method was the method used to build the English Channel Tunnel between the United Kingdom and France. In the bored tunnel method, a huge machine called a tunnel boring machine (TBM) excavates and builds the tunnel. A TBM can be used at any depth and through multiple ground conditions. However, due to the size of a TBM, they are difficult to transport, thus making them impractical for many smaller projects.
Clay Kicking Method
The clay kicking method is one of the oldest methods in tunnel construction. As its name suggests, it is used in ground conditions that are mostly clay-like. The clay kicking method works for small tunnels, such as those used for sewage or plumbing pipes. In the clay kicking method, workers create a borehole, then place the clay kicker at a 45-degree angle to bore the tunnel.
Shaft Method
The shaft method usually works in conjunction with the bored tunnel method. The shaft method is generally at the entrance and exit of a bored tunnel. In the shaft method, workers build the tunnel at a great depth and build up a concrete shaft from that depth. These shafts help ventilate the tunnel.
Pipe Jacking Method
The pipe jacking method is when a tunnel needs to go under existing infrastructure, such as a road. In this method, a special pipe is driven into the ground using hydraulic machines.
Box Jacking Method
The box jacking method is the same as pipe jacking, but instead of pipes, workers use concrete boxes.
