This is one of many steel structures that pepper the Esplanade. The walk-way/recreational area is home to a number of parks, hotels, tennis courts, sun bathing areas, etc. It's a very popular place for locals since it's out of the way and not very close to public transportation.
Each time my wife and I head to the Esplanade -- it's almost like a mini-getaway. It's peaceful and beautifully kept.
The Esplanade sits between West Street and Belford Harbor Way. If you are in the area on a warm sunny day swing by.