Kemper Arena Roof
Collapse
Introduction
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Background
Structure Design
Failure Scenario
Technical Explanation
Engineering Failures
Summary
Background
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Built in Kansas City, 1973
Used for Basketball and other events
Contemporary Design
Received an honour from the American
Institute of Architects
Structure Design
The Bolt
Failure Scenario
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June 4th 1979
One in ten year storm
73mph Winds
4 inches of rain per hour
Roof used as temporary reservoir
Inadequate drainage – ponding
1 acre of roof collapsed
Increase of pressure blew out walls
Technical Aspects of Failure
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Steel trusses supporting RC roof
For 6 years, hanger assembly connections
subjected to at least 24,000 oscillations
Introduced oscillating variations in the
tension of the bolts (4 x A490)
Particular bolts not resilient to variable loads
Caused fatigue in metal
Failed at 1/3 design capacity
Technical Aspects of Failure
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Roof used as temporary reservoir during
storms
Inadequate drainage caused ponding effect
Roof began to sag and more water
accumulated
Bolts eventually failed under load
Domino effect caused whole roof to collapse
Engineering Failures
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Steel codes warned against using the type of
bolt under variable loads
Drainage from roof inadequate, eight 5’’
diameter drains used, 55 needed for one in
ten year storm.
Variable loads probably not taken into
account in design
Summary
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Causes of Failure
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Wrong bolt selection
Inadequate drainage
Bad design
What is there to be learned?
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Dynamic loading taken into account
Building regulations and standards