The John Hancock Tower Glass Failures (1970s)
* The John Hancock Tower Glass Failures occurred shortly after the completion of the 60-story John Hancock Tower (now 200 Clarendon Street) in Boston in 1976. The skyscraper featured a sleek, modern design with large, blue reflective glass panels covering its exterior. However, soon after construction, many of the massive window panels began cracking and, in some cases, falling from the building-especially during high winds.
* The failures were caused by a combination of design and engineering issues. The double-pane glass units were too rigid and could not adequately withstand wind loads and thermal expansion. Structural movement of the tall, narrow building placed additional stress on the glass. As a result over 10,000 windows had to be replaced, at a cost of millions of dollars.
* The incident became a major case study in architectural engineering, highlighting the importance of accounting for wind forces, material behavior, and structural flexibility in skyscraper design. Despite its troubled start, the John Hancock Tower is now considered an iconic and successful example of modern architecture.
NO COMMON SENSE
ANALYZE THE EXAMPLE
* Which supports and barriers were in play?
* What were the dynamics?
* Who, or what, won the Tug-of-War?
* Discuss the outcome with your friends and family.
* Use Post #4 as a reference for the relationships and dynamics between supports and barriers.
