Design Issues

Faulty Design Led to Minnesota Bridge Collapse, Inquiry Finds

Investigators said Monday that the Interstate 35W bridge in Minneapolis, which collapsed into the Mississippi River on Aug. 1, killing 13, came down because of a flaw in its design.  The designers had specified a metal plate that was too thin to serve as a junction of several girders, investigators say.  ...  The I-35W bridge was of a type called “fracture critical,” meaning that the failure of any major member would cause a collapse, because it had no redundancy. The design is lighter and less expensive to build, but has gradually fallen out of favor with highway departments.

Controversy Dogs Inquiry on Bridge Collapse

The design of the bridge that failed was no good from the day the span opened, the board said: an engineer in the mid-1960s had specified gusset plates, the big sheets of steel that tie girders together, of half-inch thickness when they should have been an inch thick.

Three Chinese Engineers Arrested Over India Chimney Collapse
BBC News (1/13/2010)

"Three Chinese engineers have been arrested in connection" with a chimney collapse last year in India. "A chimney caved in on workers during construction at a thermal power plant in Korba district, killing 41 people last September" in the state of Chhattisgarh. "It is not yet clear what caused the accident, but officials from all companies involved have been detained. Police have already arrested four officials from two Indian firms in connection with the incident."

How much does a house weigh?

 

Problem Solving
from How Breakthroughs Happen, by Andrew Hargadon

If your thoughts are always precisely ordered, you are probably a fairly limited problem-solver.

...your mind is not going to allow widely disparate thoughts to coexist long enough to combine.

The ability to tolerate chaos is a must.

 

The solution of a complex problem is a messy process.

Rigorous and logical techniques are often necessary, but not sufficient.

You must usually deal with:

 

Is is poor planning to not allow adequate time for incubation in the solution of an important problem.

 

Want to Engineer Real Change? Don't Ask a Scientist.

 

Product Life Cycle

 

Construction / Manufacturing


Photo from trussnet.com.
Photo from trussnet.com.

Photo by Jeff Thomas near Rolla, Missouri on February 10, 1999.
Photo by Jeff Thomas in Saint Louis, Missouri on February 1, 1999.

 

Environment, Age


Photo by Jeff Thomas near Springfield, Missouri on March 24, 2000.
Photo by Jeff Thomas near Rolla, Missouri on February 13, 2002.

Photo from trussnet.com.
From advertisement in Desktop Engineering, March 2001, p. 47 for Noran Engineering.

 

Material Properties

metal wood

 

Lowe's, the Original Home Improvement Warehouse of How-To Information, web site. http://www.lowes.com/lowes/HOWTO/LIBRARY/miscell/woodstrt.asp