In addition to the domestic ones, which is the most famous bridge do you know? Many people may think of Golden Gate Bridge in San Francisco, USA. Built in 1937, the bridge has maintained the longest and highest world suspension bridge record for decades, and has been destroyed again and again in movies, such as Godzilla, Pacific Rim, Terminator, X-Men, etc., but in reality it has always been as solid as a rock and almost became a symbol of the United States. However, in a large-scale event where many people participated, the Golden Gate Bridge was almost destroyed by humans themselves.
This is on May 24, 1987, the Golden Gate Bridge held a commemoration of its 50th anniversary. Residents of San Francisco and Malin County Lin County respectively rushed from both sides of the bridge to the bridge head. When they met in the middle, about 300,000 people had gathered on the bridge deck, sandwiched in the middle, and no one could move. At both ends of the bridge, there were still 500,000 people coming continuously.
At this moment, the people on the bridge were horrified to find that the bridge was like drunk and began to shake left and right. The two 227-meter-high bridge towers also began to tilt toward the middle, and the steel cables on the bridge also began to tighten. According to later calculations, the bridge deck in the center of the bridge had sagged more than 2.1 meters under the pressure of 300,000 people!
Luckily, the organizers soon discovered the abnormality and announced in time that the bridge was closed, but 300,000 people were still trapped on the bridge and were completely evacuated after a few hours. Gary Gary Giacomini, then chairman of the Bridge District Council, said in fear that if others continued to flock to the bridge, the bridge would likely collapse.
But Bridge engineer later checked and believed that although so many people were crowded on the bridge, the bridge was structurally safe at that time and did not exceed the design load of the bridge. When designed in the 1930s, the bridge was designed to be vertically deformed at 4.9 meters, and without permanent damage under the left and right deformation of 8.2 meters. The original design load was 1 foot and 4,000 pounds, but after the renovation in the mid-1980s, it increased to 5,700 pounds. At that time, the load on the bridge was about 5,400 pounds per foot, not to mention that there was 50% redundancy when the bridge was designed.
Whether there was a risk of collapse at the time of the Kinmen Bridge, such large-scale celebrations were considered unwise. Since then, the Kinmen Bridge has never experienced such a large load again. Later, the 75th anniversary commemoration no longer allows people to walk through the Kinmen Bridge. On the one hand, it may be a load problem, and on the other hand, it is worried that more people will cause stampedeship or terrorist attacks.
However, a celebration actually allowed 300,000 people to squeeze on a bridge, and 500,000 people tried to walk onto the bridge deck. It was an extremely terrifying thing in any case. Didn’t anyone expect it to exceed the load or cause trampling due to crowding? What's more, the abortions are still rushing from both sides to the middle. It's so scary to think about it now. There shouldn't be such a stupid thing in today's society.
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