bridges

Name: Sheikh Rashid bin Saeed Crossing
Where: Dubai, United Arab Emirates
Cost: $817 million
Estimated Completion: 2012
The Challenge: Construct the world's tallest arch bridge on a bed of sand

As a child growing up in northern China, Yan Xiao loved flying kites. A born engineer, he made them himself out of paper sails and plain bamboo frames. The kites were durable and cheap. Xiao left China at age 22 to study civil engineering in Japan and the U.S. but returned as a visiting professor at Hunan University in 2002. On a trip to the region’s vast bamboo forests, the memory of those kites gave the 47-year-old Xiao a flash of inspiration: Bamboo was strong enough for kites, but he suspected that it could be fortified to make even sturdier things, like bridges and houses.

Just a few weeks ago, the new St. Anthony bridge in Minneapolis opened, to a heavy stream of commuter traffic. On August 1, 2007, the original bridge collapsed, killing 13 people and injuring more than 100. The National Transportation Safety Board will issue an official report on the bridge collapse next month, but the likely cause has to do with gusset plates that were poorly designed in the 1960s. There are still 12,600 similar "steel deck truss" bridges in use in the U.S.