Report on Minnesota I-35 Bridge Collapse

Two links to news stories about the pending NTSB report on the collapse of the I-35 bridge in Minneapolis, MN. Check back; I plan to update this article with additional links as they become available.

News articles from 12 and 13 November:

• AP: Safety Board to release report
• Duluth: State of Minnesota improves bridge inspection process
• AP: Extra load of construction material contribute to collapse
• AP: Design errors led to collapse

NTSB Presentation and related articles:

• NTSB Official Press Release
• Synopsis of NTSB conclusions
• Presentation by Jim Wildey on conclusions of investigation (11 Mb pdf)
• Links to other presentations and flash or wmv animations

Anyone who has seen my class lecture on the static equilibrium calculation for the gusset plate (based on the January 2008 NTSB Interim report (400 kb pdf) about gusset plate design flaw) will recognize many of the details in this presentation.

• WP: article on the report
• ASCE article about the report
• and collection of ASCE info on the investigation
• CNN: Design flaw led to collapse
• AP: Design errors led to collapse (includes photo of deformed gusset plate)

The final NTSB report does not seem to be in their publication archives yet. Based on the publication dates, it might not appear there for some time.

Fourier Analysis of the Beatles

I mentioned this in class late last week:

The mathematical technique of a Fourier Transform (see pg 230 of the Wolfson physics textbook we use, but also any number of math or physics textbooks) has been used to solve the mystery of the unique opening chord of the Beatles' "Hard Days Night". The mathematical software used to do this is capable of isolating the fundamental and all harmonics of a note played by a particular instrument, which made it possible to find the missing fourth instrument (George Martin on piano) responsible for the sound.

The article in Wired includes a sample of this chord, and a link to the pdf version of the report.

Computer aided bridge inspection

News story forwarded to me by my dad:

German scientists say they have developed an image-processing software program that automatically detects irregularities in bridge materials. (United Press International)

Quite interesting. This program would probably have warned of the defect in the Minnesota I-35 bridge that was in photographs taken several years before it collapsed, but not noticed at the time.

IMPT. ENGINEERING CLUB MEETING FRI. 10/31/08 @ 2:30 SM 260

In case you are not on Vernon’s email list… Here is a
MESSAGE FROM VERNON

I hope to see all club members at SMA 260 at 2:30 this Friday. In addition we will be going over our club roster for submission to the SOC. If any members would like to email me their name and student id number in advance to the meeting for convenience, feel free to do so. The Space Grant Consortium has received our W-9 form and we should be receiving funding for the rocket competition soon. All who are interested in continuing research for our rocket team should attend the meeting. Next month we begin building and planning for testing!!!
Vernon Babich
Engineering Club Chair
850-510-2473
________________________________________

Space Station Viewing

The International Space Station (ISS) can be seen in skies over Tallahassee tonight (Friday, October 10) between 7:47 pm (rising in the NW) and 7:52 pm (setting in the SE). It will be very high in the sky (68 degrees above the horizon, just 22 degrees from overhead) to the NE at about 7:49. It should be very bright (-2.4 magnitude).

You can use this link

• The Heavens Above web site (set up for Tallahassee)

to get detailed information for the ISS and other objects orbiting the earth.

Tour of Florida DOT Structures Research Center

Plan ahead! Friday, October 10, at 2:45 pm.

We have scheduled a tour of the Florida Department of Transportation's Structures Research Center, which is located in Innovation Park at 2007 East Paul Dirac Dr. (See map info below.) It is kitty-corner across the street (south east) from the Mag Lab. Plan to leave TCC right after your class gets out so we can meet at the building by 2:45.

This will be a real treat for any Civil Engineers, but my student (who works there) says it should also interest electrical and mechanical engineers because of the instrumentation and equipment used to do the tests. This facility is used to "test to failure" (engineer-speak for "break") bridges. Example: take a 60' concrete beam that would normally be part of a bridge, and measure everything that happens as they break it. We can't actually witness one being broken (that happens this week), but we should be able to see the results and how it is done.

• Example from their web site, showing I-75 bridge beam to be tested
• pdf of report about test of I-75 bridge beam

The easiest route from TCC zigzags from Pensacola to Mabry (turn at Goodwill) to Roberts Road (turn left immediately after crossing the railroad tracks) to the back entrance for Innovation Park (right at the top of the hill, just before TurboCor), then left around the circle to Pottsdamer Road. Parking is off of Pottsdamer and there is additional parking across the street and to the south.

• Follow this link to a Google Map of the area

TCC should be in the upper left corner of the page and the Research Center (marked with an A) in the lower right corner of the view if your browser display is similar to mine. I've also embedded the map below, but you can't see TCC in the smaller view of the embedded map.


View Larger Map

"REPORT" WRITING

OK, Vernon is going to write a summary of the ASME SLS @ ORLANDO.
Thanks, Vernon.

Now I need somebody to step-up and write a summary of the HOPKINS TOUR & COOKOUT.

--- DJ