Of Live Load and “Love Load”, Bridges, Bats, and Locks

Parisian bridge collapses under the weight of love

A $24.4 million dollar traffic fine, an 80,000 pound live load that takes off (literally) for 30 minutes every evening, and a structure that stands up well in the face of war, but collapses in the face of love…what do they all have in common?   They all relate to bridges, and the unanticipated loads that they may have to endure.

We know that the job of the engineer is not only to design a structure that safely withstands its anticipated loads, but likewise to accurately anticipate those loads.  A good design may go for naught if it doesn’t suitably consider the possibility of every load that it may eventually experience. Continue reading

The Statue of Liberty: the World’s First Skyscraper?

The Statue of Liberty, once the tallest structure in New York City,
surrounded by its taller descendants

Happy July 4, everybody!  In the United States, this is a day to celebrate our nation’s independence, and give thanks for the centuries of freedom that we have enjoyed since our founding on July 4, 1776.  There is no greater symbol of that freedom, than the Statue of Liberty (official title: “Liberty Enlightening the World”) – the glorious structure that since 1886 has welcomed millions of immigrants, many of whom were fleeing repression in their native lands.

Growing up in New Jersey, I saw the Statue of Liberty often.  Catching that first glimpse of it while driving down the New Jersey Turnpike or while heading into New York to witness yet another Mets’ baseball loss was always an exciting moment, and today when I fly into New York it still is.  To me (and many others) the statue is both beautiful art and one of the greatest symbols of all that is right with this country.  But as a structural engineer I have another reason to get a lump in my throat when I see it — did you know that the Statue of Liberty may well have been the world’s first skyscraper? Continue reading