Will leaning tower of Pisa fall down? If so, when ?
Perhaps engineer Bonanno Pisano failed to consider the consequences of designing a 185-foot-tall tower with a stone foundation only about ten feet thick. And this thin base rests on soft sand, rubble, and clay -- not firm underpinnings for an almost 16,000-ton tower. The structure continued to settle unevenly.
Nonetheless, construction continued. To make up for the tilt, builders made each new tier a little taller on the short side -- but the additional stone only made the tower sink more. Upon completion in 1350, the tower was leaning a full 4 feet, 7 inches from vertical.
Up in the belfry, the weight of the bells caused the structure to tilt even further. By the late 20th century the tower was leaning more t ...more