Wonderful Engineering

This is How Modern Bridges Are Constructed In The US

Considering the advances that have been made in the technology and science department, it doesn’t come as a big surprise when you see construction industry achieving the miracles that it currently is. With the advances came more cost-effective methods and more approaches to constructing some really amazing structures. Without getting into the detail about that, let’s talk about how bridges are made in the USA. 

Wait, what? Bridges? Isn’t that a simple way of construction? Bridges are being constructed since like forever, right? But have you ever stopped to wonder that just exactly how far the construction techniques have evolved? Let’s talk about the construction of a bridge over the Saint Croix River. A time-lapse video has been released by the Minnesota’s Department of Transportation that shows the bridge’s construction and it is nothing short of a marvel to stare at.

We’ll briefly talk about the construction process before we let you watch the video. So, the construction begins with a work platform that is made to float on the surface of the water. Caissons are then drilled 150ft below the water and a box-shaped dam is constructed. Once the dam’s construction is complete, the platform is sunk to the riverbed. This platform will now serve as the base for concrete footing of the structure. A Column is erected upon this footing and once the column clears the water surface, the dam is removed. Crane are used for raising precast bridge segments into place followed by attaching them to the bridge by using tensioned cables. The St. Croix Crossing is slated to be completed by fall 2016.

Check out the time lapse video below and let us know what you think of it.