Modern bridge building like an Egyptian
Using a method likely perfected by the builders of the Egyptian pyramids, workers at the Belleair Causeway bridge just reached a milestone in construction.
For the second time in the U.S. bridge-building history, construction workers employed a technique called “incremental launching” to drag 7,200 tons of concrete deck into place. It works in the way archeologists believe the pyramids were built, by dragging huge construction components into place and aligning them.
The bridge workers used heavy-duty hydraulic jacks and Teflon pads, plus an ingredient found in every kitchen - dishwashing detergent. Giant slabs of bridge deck were dragged across a series of piers to form the east and west approaches of the Belleair Causeway bridge. By the time the last slab on the west approach was cured, connected to the others and dragged into place, the bridge deck weighed about 7,200 tons.
Think of 2,200 Hummer vehicles, without wheels, dragged across the ground at the rate of about a quarter inch every seven seconds.
Engineers say the dragging method is cheap, safe and simple.
Excerpted from an article bt Mark Douglas for msnbc
Great Pyramid was on the verge of collapse during construction
Bob Brier, also known as Doctor Mummy, along with an architect and a team of software specialists, has determined that huge support beams inside the Great Pyramid at Giza cracked as final construction was under way 4,500 years ago.
The team used 3-D modeling software that measures stresses in buildings, cars and airliners and found that the pyramid cracked up when three things happened: One wall of King Khufu’s burial chamber settled, stone rafters in a room above the chamber slipped, and the height of the pyramid reached 392 feet.
The team found that the pyramid’s architect, Hemienu, cut a tunnel into a sealed space above the burial chamber to assess the damage and filled the cracks with plaster that would indicate if the cracks were widening. The ancient fix-it job worked, the beams held and the pyramid was complete.
Brier will present his findings at the Microsoft Innovation Management Forum in Redmond, Wash., on Tuesday.
