The section on London Bridge is about how the bridge was first built, and how it has changed over the past thousand years. It was first built in AD43. At the time, they built it in wood. Around 950 years later, the Danes raided London. They sailed up the river, and managed to pull the bridge down. The bridge later were repaired, but was replaced by a stone bridge only some decades later. This bridge lasted for almost six hundred years. The next bridge made, lasted for a shorter period, until 1967, when a new bridge was built to make it wider due to the increased traffic. This is the London Bridge which stands today.
The text I liked best was the one about how the last bridge to be replaced was sold to America. An Oil Company bought it for 2.5 million dollars, and the reactions was divided. Most of British people thought it was not right that a big British landmark like this should end up in America. The Americans, on their side, thought it was great. The man who sold the bridge, Ivan Luckin, had a nephew named Terry Bedford. That’s the man you want to speak with if you’d like to know more. He wrote a very interesting account of sale. He tells stories about the bridge which his uncle told him as a teenager.
I worked with the section on “about bridges.” This was a good choice, because it was not too hard, and I learnt a bit from it too. It started with an article about the last piece of Tacoma Narrows Bridge, and continued with small texts and articles about Aquaducts in Rome and The Roseman Covered Bridge.
I worked with this section in various ways. I skim read a part of it, wrote some small notes, and the article about Aquaducts, I read carefully and precisely.
A bridge to remember
There are many different bridges in the world. Many of them is very famous, like the London Bridge. Reasons for fame amongst bridges is the size, the history behind it, or simply how it looks. But some bridges becomes famous for its tragic end. The Mississippi River Bridge is one of them.
Construction began in 1964, and the structure was completed in 1967. The bridge was built in steel, and was built over the Mississippi River. It was an eight-lane bridge, and about 200.000 cars drove across it every day.
The disaster happened on august 1st at 06.05 pm. It was rush our on the bridge, and around 100 cars was crossing at the time it collapsed. It was the central point of the bridge which had been constructed badly. A security camera captured it, and it’s amazing and terrible pictures.
Thirteen people died in this accident, and 145 injured. That is shocking numbers. A school bus with 60 pupils inside was lucky to not fall into the river.
The president of the U.S.A., George W. Bush came to the scene 3 days after, and met two of the families which had lost a family member.
How it happened? This was the answers from chairman of National Transportation Safety Board, Mark Rosenker:
Why did the bridge collapse? The bridge collapsed because there was under-sizing of the gusset plates. And there were approximately eight positions where that occurred.
What is a gusset plate? What is it there to do underneath the bridge? Well, simply stated, it is a component of the bridge which ties the beams together. It is normally considered a stronger part of the bridge, even stronger than the beams that it ties together.
Now, when you released this information, the results of the investigation, you stepped back from calling this the cause of the collapse. Why, if you're so sure that these plates failed, are you not ready yet to say, "This is why the bridge fell down"? Well, it is why the bridge fell down. It broke. It could not support the weights. The question is what was different on that day, on August 1st at around 6 o’clock that was different than the day before, the weeks before, the years before? That's what we're trying to understand.
Chairman Rosenker, thanks for joining us. It's a pleasure. ( Source )