Rising 630 feet above the Mississippi River, St. Louis’s Gateway Arch stands as a modern structure that memorializes the city’s place in American history. The arch symbolizes two important aspects of the American spirit: the adventurous bravery evident in the numerous travelers who headed West through St. Louis and the technical prowess of designers, builders, and welders who constructed the monument.
The iconic Gateway Arch is just one structure that would not exist without the invention and evolution of modern welding techniques. In this blog, we’ll examine five significant structures made possible by welding.
1. The Gateway Arch in St. Louis
Workers used numerous welding techniques to construct this geometric structure. The arch’s legs consist of small triangle-shaped sections that were assembled individually in Pennsylvania.
Each triangular section below 300 feet high has two walls: an outer stainless steel wall and an inner carbon steel wall. Welders used butt welding techniques on both walls. Builders also used MIG, or metal inert gas, welding to join the polished stainless steel that forms the arch’s exterior walls. These stainless steel plates also had long rows of studs welded to them.
To attach the inner and outer walls, welders chose spot welding. This nearly heatless welding method ensured that the steel would not warp and become misshapen. The assembled triangular sections were welded to train gondola cars so they would stay in place during the trip to St. Louis. Finally, the individual sections were welded together to form the historic arch.
2. Yankee Stadium
The new 2009 Yankee Stadium sits just one block north of the where the original Yankee Stadium was located. The updated version currently holds the top spot on the list of most expensive sports arenas ever built. More than 53,000 baseball fans can gather to watch games inside this huge structure.
To please Yankee fans, designers of the new stadium incorporated elements from its predecessor. One such element, the white frieze surrounding the roof, consists of zinc-coated steel sections. Welders joined these sections together. The frieze provides structural support for the upper decks and stadium lights. Consequently, steel beams do not block fans’ views of the field below.
3. Liberty Ships
During World War II, the United States needed to quickly build inexpensive ships for cargo transport. American military forces adapted a British design to create Liberty ships. These boats lack aesthetic beauty and earned insulting nicknames such as “Ugly Duckling,” but they served their purpose and helped move goods safely from the USA to Europe.
More than 2,700 Liberty ships were built during the war. A crew could assemble an entire Liberty ship in around 42 days once the process was streamlined. The secret to the quick construction was submerged arc welding. Earlier similar ship models mainly used rivets, which take longer to install.
Some Liberty ships experienced cracks in their hulls or decks. But those cracks occurred because of the brittle steel used to make them, not poor quality welding. In fact, the welded hulls actually allowed the cargo-loaded ships to travel farther than riveted ships could have.
4. The Grand Canyon Skywalk
Before 2007, visitors to the Grand Canyon had to observe its grandeur from observation decks on the edge of its rims or descend into the canyon itself. But today’s visitors can look down into the canyon if they dare to venture onto the Grand Canyon Skywalk. (The bridge is safe but might be scary for people with a fear of heights.) This horseshoe-shaped bridge has a transparent floor and extends 70 feet over the canyon’s rim.
To construct this wonder of modern engineering, crews welded together more than a million pounds of steel. The main technique used was an efficient submerged arc welding method that employed both alternating and direct currents. These welds make the structure extremely strong. It can withstand earthquakes up to an 8.0 magnitude and hold 70 million pounds of weight.
5. The Detroit-Windsor Tunnel
The last landmark on our list is also the oldest. Built in 1930, the Detroit-Windsor Tunnel runs below the Detroit River and into nearby Windsor, Ontario, Canada. Workers first attempted to build the tunnel in the 1870s, but obstacles such as sulfur gas and limestone made the project expensive and dangerous.
Luckily, by the 1920s, new techniques, including arc welding, made the tunnel possible. The Detroit- Windsor Tunnel is just under one mile in length (5,160 feet), but it contains around 65 miles of arc welding. Today, this tunnel serves as the second-busiest border crossing between the United States and Canada.
The five structures listed above show that welding has played a significant role in the creation of modern engineering feats. If you need to build structures that will stand the test of time, incorporate welding into your building process. Your designs may not become iconic like those listed here, but the final structure will be firmly fastened together and ready to withstand strong forces.