Questions: Engineering Failures and Lessons Learned
3 questions to test your understanding
Score: 0 / 3
Question 1 Multiple Choice
The Tacoma Narrows Bridge collapsed in 1940 primarily due to:
AAn earthquake
BAerodynamic flutter caused by wind interacting with the bridge's flat, solid deck design
CExcessive vehicle traffic
DA manufacturing defect in the cables
The bridge's thin, flat deck caught the wind like a sail, causing it to oscillate with increasing amplitude (a phenomenon called aeroelastic flutter). This was poorly understood at the time. The failure led to fundamental advances in bridge aerodynamics, and modern suspension bridges are designed with aerodynamic decks and wind tunnel testing.
Question 2 True / False
Most major engineering failures are caused by a single, catastrophic mistake.
TTrue
FFalse
Answer: False
Major failures almost always result from a chain of contributing factors: design oversights, material variations, communication failures, schedule pressure, and missed warning signs. The Swiss Cheese Model describes how failures occur when multiple layers of protection each have small holes that happen to align.
Question 3 Short Answer
How did the Hyatt Regency walkway collapse in 1981 change engineering practice?
Think about your answer, then reveal below.
Model answer: A seemingly minor design change (switching from a single continuous rod supporting two walkways to two separate rods) doubled the load on the critical connection, causing collapse during a crowded event. This led to reforms requiring that design changes be reviewed by the original structural engineer and that connection details receive as much scrutiny as primary structural members.
The collapse killed 114 people and was caused by a change made during construction that was not properly analyzed. The lesson was that every design change, no matter how small it seems, must be evaluated for structural impact. It also reinforced the importance of clear communication between designers and builders.