Sunday, August 18, 2013

How Can a Flat Bridge Be "Extradosed"?

The bridge over the Quinnipiac River may be more expensive  and less efficient than necessary.

This is certainly not my opinion because I am not an engineer or bridge designer.  This is the stated stand of the Structural Engineering Forum of India.

Before we get into that, what exactly is an "extradosed" bridge? Just because the state Department of Transportation calls the structure that in press releases, does not excuse publications that print the press releases from explaining.

To summarize, extradose is the outside measure of an arch. The inside curve is called, what else, the "intradose." Architecture is filled with esoteric names for things. Know what "ogee" means?

Architecturally, a Gothic arch with a peak is made out of two ogees. (right)

 "Ogive" describes the  shape of the nose of a rocket or a bullet. (below)


 There are dozens of words for different curves. The Sears-Hack Body, for instance, is a an aerodynamic shape that produces the least drag.

If you're sitting around with nothing to do, search "names of curves" on Google. 

Now, the bridge over the Quinnipiac does not seem to have much extradose, or extrados.

Extradose and iontradose
 In fact, it is a cable-stayed extradosed design. This looks superficially like a suspension bridge, but is fundamentally and physically different.

Suspension bridges use much larger towers to carry a thick "caternary" of cable. Smaller cables connected to the large one are connected to the bridge deck, holding it up. 

A cable-stayed bridge uses cables from shorter towers to connect directly to the bridge deck.  The cables also perform different work. Since they meet the deck at a low angle, they tend to add to the longitudinal strength of the bridge. 

Cable-stayed extradosed bridges have a box-girder bridge deck, but are thinner than  plain box-girder construction as typified by the old  Q bridge that is now being torn down.

The idea of cable-staying a bridge dates to the 19th century. Now cable-stayed exterdosed bridges are used because they require shorter towers, have less of a footprint than box-girder bridges, and they look kind of cool.

Lots of cable-stayed extradosed bridges have been built in Europe and Asia. Which brings us back to the Structural Engineering Forum of India. India has many of its own cable-stayed extradosed bridges.

Writing in October of 2012, Dr. Narayanan said:

Extradosed bridges are relatively expensive and material inefficient. Almost any span that could be bridged by an extradosed bridge could be spanned more inexpensively with a continuous girder, or more efficiently (but at even greater cost) with a cable-stayed. In most cases the spans are short enough that the use of cables at all is an aesthetic rather than engineering-necessitated choice. This does not imply that is a "bad" choice, since in some cases the difference in cost and efficiency is small, and the extradosed type is a very elegant form. 

This is one person's views, although Subramanian is the author of several books on the subjects of concrete, bridge design, and related topics. He probably knows as much as the people who designed and are carrying out the Quinnipiac project at glacial speed. 

So, there you have it.  Seems like whoever runs bridge construction in Connecticut could have saved money and perhaps decades, by building a new,  bigger  box-girder bridge than by selecting a nonsensically named "extradosed" design. 

Just food for thought as you negotiate the ever-changing lanes and soaring ramps of the Pearl Harbor Memorial Bridge.

 Let's hope it is finished while veterans of Pearl Harbor are still alive. 

Extrados(e) and intrados(e) turn up all over the place, including the design of airplane wings. 

Wednesday, August 14, 2013

You Get What You Pay For, Especially In News

The sad sack who nominally runs America on Line, apologized recently for firing someone during a conference call, which is a pretty unpleasant way to act.

Tim Armstrong, AOL chief of something or other, was informing other AOL middle managers that he was considering pulling the plug on Patch. Patch is a service provided mostly by would-be writers and masochistic "editors," who search for the "hyper-local" and post stories on the Patch web site, wherever that is.

Something like that. My impression is that editors break their backs re-writing everything, posting everything, and whatever else constitutes everything. Some media outlets call Patch AOL's "media and information platform." Please.

You could have seen the story in the Wednesday, Aug. 14 New York Times, which to its diminishing credit, still pays reporters, professional reporters, some of the best, to cover stories and then edit and print the stories on newsprint.

To digress for a moment,  the Times wants to be a newspaper and a Web presence simultaneously. The problem is that short of making people pay for what's free on Google news and other places on the Internet, the Times has no good way to make money on the Web. 

People will pay to watch baseball, football, or basketball -- or to watch pornography -- but otherwise, who wants to shell out cash for some intangible electrons? Even well written intangible electrons. That's why the Times loses tons of money on its Web edition, which comes out of the newspaper's newspaper division.

The newspaper on paper version sells at least okay. Many people are willing to pay along $700 a year to have the Times delivered every day. Now the Times is restricting un-paying Web readers to three stories a day. After reading three stories, you'll need to come up with some electronic dollars.

 This applies even to the people who pay almost a grand a year, sadly.

There is an alternative. What you do as publisher is invite people who think of themselves as reporters and/or writers to replace the real reporters, who frequently use to have advanced degrees in journalism. They also had experience, and more importantly, experience in newspaper writing.

Trust me, teaching people to write like seasoned reporters is not easy. Not in the least. Might be easier to teach them Mandarin or linear algebra. 
Following that formula, you the published, get something along the lines of Patch. Or, worse yet, "the Examiner," which pays its "freelance writers" one tenth of a cent per Web hit. Kind of hair-raising.

Ultimately, it made sense for Armstrong to downplay Patch by firing and humiliating an otherwise loyal employee.

 Better to be seen as a lout than the money-hungry purveyor of maybe-news by amateurs. 

To Heck With Cancer in Google Land

Last night I had occasion to purchase online two T-shirts that read "Fuck Cancer."

I'm entitled to buy them because I have/had/am having head and neck cancer.  Part of my throat was removed in April and then I underwent  six weeks of radiation therapy and infusions of cisplatin.

Aside from the pain and discomfort, which there is plenty of, I lost my sense of taste,  the desire to eat, some facial hair, some hair on the back of my head, and concluded with a strangely weak right arm, because surgery to remove a few dozen lymph nodes impinged on a nerve.

Also, the x-rays and chemotherapy were not beneficial to my salivary glands.

My taste and appetite returned, for the most part, my facial hair is trying to return, my arm is improving, and the back of my head may even be growing hair.  Saliva is back, most of the time.

(That is among the reasons I have not been blogging much lately).

So, I felt entitled to buy a Fuck Cancer T-shirt. 

I was not sure where I had seen them online, so I searched Google for "fuck cancer T-shirt."  But Google would not cooperate because the search is permanently set on "safe." Consequently, I turned up many anti-cancer T-shirts, but no fuck cancer.

If anyone has figured out how to turn off Google's safe search, please drop me a line. If one tries to turns if off, one is directed to "settings," which do not contain a way to turn off "safe" mode. The exercise has an infuriating circular character. 

My sense is that I could probably find all manners of hate, prejudice, violence, killing, crime. and other unsavory things on Google, no problem. Fuck cancer? Nope.

Google, for mysterious reasons, eventually "asked" me if I wanted to search for "fuck cancer T-shirts" and I responded positively. 

To sum up: I was not searching for pornography. Not every instance of a word such as "fuck" is necessarily immoral. Google's safety program cannot easily distinguish between the two.

Google eventually relented. I'm not sure why. 

But trust me. "Fuck cancer" is one of the milder feelings one has after a malignant chunk of throat is removed and then exposed to death rays and poison.