Suspension bridges are beautiful. Situated in the biggest cities in the world, a thriving city’s mass traffic often depends on them. This is a huge responsibility, considering you’d expect them to have low stability. The Pearl Bridge, in Japan, has the longest span of any suspension bridge, at 6529 feet.
They fascinate me because of their simplicity and the little support they rely on. The first suspension bridges were simpler, without vertical suspenders. This type of bridge is still considered the most efficient and sustainable design in developing countries. They are common in mountainous areas, and to cross shorter spanned rivers. It has an arc shape, due to the simpler concept, which gives it many limitations. One of the main things is that it restricts the capacity of load that can be carried.
A suspension bridge today in developed countries over longer spans and with more challenging requirements, has two tall towers, through which cables are strung. A deck is suspended from these cables, so the towers are therefore supporting the majority of the roadway's weight. The main forces are the tension in the cables and compression in the pillars. A supporting truss system beneath the bridge deck helps to stiffen the deck and reduce the tendency of the roadway to sway and ripple. A suspension bridge allows longer spans to be achieved than with any other type of bridge, requiring less material.
New York is one of my favourite cities in the world, and amongst many of its engineering defeats, is the Brooklyn Bridge. The bridge carries an average of 145,000 vehicles per day. The construction of the Brooklyn Bridge started in 1869 and took 14 years to complete.
