John Hancock Building glass cracking failure

Originally specified plate glass that cracked and fell to the street under wind loading. Required three years of total U.S. chemically-tempered-glass production (lithium-for-sodium/potassium ion exchange) to re-glaze. The classic structural-glass failure case.

Tom uses the building both as a structural-glass failure case (wind-induced suction popping windows out) and as a tuned-mass-damper case (whole floor with rotating weight to damp sway). Chemically tempered glass was the fix.

The John Hancock building over here — when I was a student they were building it, and after they first built it, the winds came along, creating a suction force, and the windows were popping out of the building and falling to the ground.

Student: The Plywood Palace?