Welding New York City Monuments

Welded wire reinforcement first appeared in the late 1800s, and in 1901 a machine that could weld wire in sheet form was invented. Although it was intended to build fences, five years later it was being advertised as concrete reinforcement. Instead of the previous slow and expensive method of using long rods of steel that had to be tied together, sheets of cold drawn steel were welded together in a crosshatch pattern at the factory and delivered to the job site, speeding construction while cutting labor expense.

New York City had lost many structures to fire by the early 1900s, and city hall was eager to somehow fireproof the many buildings. At about the same time welded wire reinforced pavement was first tried on the Long Island Parkway, which was soon copied by many cities.

Welded wire reinforced flooring made of scrap gathered from coal burning plants around the New York City area was used in the construction of Grand Central Station and the Empire State Building, this was called cinder arch concrete floor system, still in use in those landmarks today.

After the devastation suffered in Europe during World War II and the resulting labor shortage, a method was needed to quickly rebuild that was not labor intensive, and since then welded wire reinforced concrete has remained more popular in Europe than in the United States.

The more modern New York landmarks, such as the Pan Am terminal at Kennedy airport and the World Trade Center towers, were also built using welded wire reinforced construction, which provides a lot of strength to very thin concrete structures. Since it can be bent to customer specifications, any geometric design is possible while being coated with zinc and epoxy to prevent corrosion.