Left here without comment.
A professor of structural engineering takes a look at the bridge collapse in Miami. FIU Bridge Collapse: Why Müller-Breslau Matters.
The mavens of engineering, who have been screaming for more social justice and less rigor in engineering have been strangely silent this week. And the media is run by a bunch of people who had trouble with high-school algebra, so they are not much help. It was nice to see an article by someone who takes the rigor seriously.
Dr Oliver McGee is a Professor and former Chair (2016-17) of the Department of Mechanical Engineering at Texas Tech University.
Like everything else in this world, bridges are bound by fundamental rules of science and engineering — things like transverse shear stresses, transverse bending moment stresses, bridge deadweight to live-load ratios and, not the least, simple gravity of Sir Issac Newton
The bridge in Miami collapsed for a reason. It was either not designed properly, or it was not constructed properly. (Bridges that are not maintained properly will also collapse – as they discovered in Minnesota several years ago – but this bridge was still under construction.) This article goes into some to the structural engineering principles and math (at the algebra level – no differential equations) that can shed light on why bridges collapse.
Heinrich Franz Bernhard Müller (born May 13, 1851 in Wroclaw, Portland and died April 24, 1925 in Grunewald, Germany, “known as Müller-Breslau from around 1875 to distinguish him from other people with similar names”) was a German civil engineer. He made early advances in the structural analysis of continuous beams and rigid frames used in modern pedestrian and highway bridges and tall buildings.
I won’t inflict the math on you, if you are interested, click through. (Hat tip)
Clearly engineers need to concentrate more on social justice issues, and less time on calculating the tensile and compressive strengths of various materials. Miami FIU pedestrian bridge collapses, people trapped beneath | Miami Herald
Which waste-of-space university professor was complaining that engineering was too concentrated on hard science stuff like differential equations?
The PR hacks are already in action, stating how the engineering firm, “mourns the loss of life.”
The bridge was making use of an “innovative” construction method so as not to disrupt traffic so much. My guess is that, even if that method is sound, the lawyers (who wouldn’t know a differential equation from a doughnut) will tear the firm apart for not using a method that has been done a 1000 times before. Unless of course they can blame the contractor, the concrete, or something else.
March 14th is Pi day. And it’s also Einstein’s birthday.
One of the simplest ways to estimate π is to use the Gregory-Leibniz series.
π = (4/1) – (4/3) + (4/5) – (4/7) + (4/9) – (4/11) + (4/13) – (4/15) …
It is simple to understand, not simple to do. It takes 500,000 iterations to get to 5 decimal places.
The Wiki can walk you through a couple of proofs, if you are so inclined.
And also, last year’s “Most inefficient way to estimate Pi.” Now go eat some pie.
March 11, 2011: The 2011 Tōhoku earthquake, sometimes called the Great East Japan Earthquake and Tsunami. And the resulting mess at The Fukushima Daiichi nuclear power plant. Fukushima nuclear disaster: did the evacuation raise the death toll?
People are scared to death of radiation, so it isn’t surprising that governments make boneheaded decisions about what to do in the aftermath of something like this. But the truth is that radiation from Fukushima Daiichi didn’t kill anyone. The fear, and the regulations imposed – in particular the evacuation – killed a lot of people. Mostly elderly people.
But first lets deal with what didn’t happen.
The result that did not materialise was sickness from radiation. “At present, there are no cases of cancer relating to radiation, and that includes workers at the plant,” says Dr Tanigawa. Among 173 workers exposed to radiation above occupational safety limits, there may eventually be a handful of incidents of cancer, he says. But the maximum dose to Fukushima residents was below those levels. “Statistically speaking, there should be no detectable increase in cancer in the general public.”
That hasn’t stopped the fear-mongers from doing what they do.
Say it again. NO DEATHS from radiation. And yet people keep trying to compare this incident to Chernobyl. Which is comparing jumping off a chair (no big deal) with jumping off a cliff (a very big deal). They both involve jumping, right.
But this paragraph caught my attention. One evacuee and his family were listening to rumors.
“My children were saying: ‘We don’t want to die from radiation. Let’s go to Tokyo. Let’s go to Tokyo.’”
So the family moved to the Japanese capital, 200km away, which is where their troubles really began.
Now the Japanese government and The Tokyo Electric Power Company did an incredibly bad job of providing information after the tsunami. But rumors and children’s fears shouldn’t be the basis for how you live your life. But those childhood fears – multiplied across the region – basically became government policy. Incredibly stupid government policy.
2,202 died as a result of the evacuation. This is from stress, lack of medical care, and suicide. Of those 1,984 were people over the age of 65.
The question is rather whether people should have been kept away for weeks, not years. “With hindsight, we can say the evacuation was a mistake,” says Philip Thomas, a professor of risk management at the University of Bristol and leader of a recent research project on nuclear accidents. “We would have recommended that nobody be evacuated.”
The excess radiation that would have accrued to people living in the MOST affected villages was a dose that was allowed in the industry as little as 30 years ago. You could have educated those people and given them a choice of what to do. (Free choice? Individual liberty and individual responsibility? We can’t have that!)
This all goes back to a general ignorance about radiation and risk. And the persistence of the Linear No-Threshold Theory of radiation exposure. Which wasn’t even state-of-the-art in 1946 when it was proposed.
For some radiation info, consider The Banana Equivalent Dose, or Your Food is (always has been) Radioactive and xkcd’s great Radiation Chart, which points out a few things. Like people who mostly sleep next to another person get a higher yearly radiation exposure than people who mostly sleep alone.
Where would we be without peer-reviewed scientific journals? (I love it when stuff like this happens.) Predatory Journals Hit By ‘Star Wars’ Sting | Watts Up With That?
A number of so-called scientific journals have accepted a Star Wars-themed spoof paper. The manuscript is an absurd mess of factual errors, plagiarism and movie quotes. I know because I wrote it.
This is a masterwork of snark, and the original spoof paper is beautiful, even if you aren’t a Star Wars fan. (The last movie I like was, “The Empire Strikes Back.”)
I have family in Illinois that are dependent on pensions, so I can’t even think rationally when it comes to the insanity. I’m just incensed. The Silicon Graybeard: The One Factoid About the Illinois Mess You Can’t Miss
I will highlight one thing that he “isn’t saying” and say it plain. There is a LOT of corruption in Illinois politics.
I’m not saying it’s related to the fact that as soon as I started to type “Illinois politicians pension promises” into my search bar, before I finished the second word it offered to autocomplete with “Illinois politicians in jail”. As the saying goes, I’m not not saying it either.
4 of the last 7 Illinois governors did time in jail. Mostly for federal corruption, and some for stuff they did after they left public office. (You remember Rod Blagojevich, I’m sure.)
Then there is Tony Rezko, who should have been a millstone around Obama’s neck, but the media wouldn’t report on it. Rezko – who did favors for Illinois politicians on both sides of the divide, helped Obama buy a house in Chicago. The deal was shady, and a lot of people thought it amounted to a “gift” of some size, but by the time anyone cared, Obama was in Washington, and Rezko was in prison.
Rezko’s behind-the-scenes connection in the Obama house deal became public as Rezko revealed personal financial details as he sought to post bail.
While Rezko’s wife paid the full asking price for the land, Obama paid $300,000 under the asking price for the house. The house sold for $1,650,000 and the price Rezko’s wife paid for the land was $625,000.
That “piece of land” was adjacent to the Obama house, and Rezko later sold some of it to the Obama family. Water under the bridge at this point.
For a rundown of the History of Illinois Political Shenanigans see the post I wrote in 2009. Pay particular attention to the part about Paul Powell. His story tells you everything you need to know about politics in The Land of Lincoln.
“There’s only one thing worse than a defeated politician, and that’s a broke one.” – Paul Powell, one-time Illinois Secretary of State.
When Powell died, in 1970, $800,000 in cash was found in his lodging. In suitcases, and shoe-boxes.