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A catastrophic failure is a sudden and total failure of some system from which recovery is impossible. Catastrophic failures often lead to cascading systems failure.

The term is most commonly used for structural failures, but has often been extended to many other disciplines where total and irrecoverable loss occurs. Such failures are investigated using the methods of forensic engineering, which aims to isolate the cause or causes of failure.

Structural failure

Examples of catastrophic failure of engineered structures include:

• The Tay Rail Bridge disaster of 1879, where the center half mile of the bridge was completely destroyed while a train was crossing in a storm. The bridge was badly designed and its replacement was built as a separate structure upstream of the old.
• The failure of the South Fork Dam in 1889 released 4.8 billion US gallons of water and killed over 2,200 people (popularly known as the Johnstown Flood).
• The failure of the St. Francis Dam in 1928 released 12 billion US gallons of water, resulting in an official death toll of 385 people.
• The collapse of the first Tacoma Narrows Bridge of 1940, where the main deck of the road bridge was totally destroyed by dynamic oscillations in a 40 mph wind.
• The De Havilland Comet disasters of 1954, later determined to be structural failures due to unanticipated metal fatigue at the corners of square windows used by the Comet 1.
• The 62 Banqiao Dams failure event in China, result of Typhoon Nina. Approximately 86,000 people died from flooding and another 145,000 died during subsequent disease, total of 231,000 deaths.
• The Hyatt Regency walkway collapse of 1981, where a suspended walkway in a hotel lobby collapsed completely, killing many people on the structure and those below.
• The Space Shuttle Challenger of 1986, in which an O-ring of the rocket booster failed, and the entire vehicle was lost.
• The collapse of the Warsaw radio mast of 1991, which had up to that point held the title of world's tallest structure.
• The Space Shuttle Columbia of 2003, where damage to a wing caused at take-off resulted in total loss on re-entry.
• The total collapse of the multi-span I-35W Mississippi River Bridge on August 1, 2007

Catastrophic failure in centrifugal pumps

A catastrophic failure of a centrifugal pump can occur if the liquid within the pump casing is allowed to vaporize. To prevent flashing due to overheating of the fluid, a flow must be maintained through the pump to keep the liquid below saturation temperature.

If a temperature rise of 15°F is accepted in the casing - minimum flow through a centrifugal pump can be calculated as

q = PBHP / 2.95 • cp • SG (1)

where

• q = minimum flow rate (gpm)
• PBHP = power input (BHP)
• cp = specific heat capacity (Btu/lb °F)
• SG = specific gravity of the fluid

Computer failure

The term catastrophic failure is occasionally used in computer software to indicate an unexpected error from which the system cannot meaningfully recover. This usually results in a screen of death.

See also

• List of bridge disasters
• Seismic performance
• Structural collapse
• Structural failure
• Resonance disaster
• Risks to civilization, humans and planet Earth

References

• Richard Feynman, Ralph Leighton (contributor), W. W. Norton, What Do You Care What Other People Think?, 1988, ISBN 0-553-17334-0
• Peter R. Lewis, Beautiful Railway Bridge of the Silvery Tay: Reinvestigating the Tay Bridge Disaster of 1879, Tempus, 2004, ISBN 0-7524-3160-9

• Construction terminology
• Civil engineering
• Failure