The Stabilization of The Leaning Tower of Pisa: A Feat and an Anomaly

In 1173, when the construction of the Tower of Pisa was underway, nothing was suspected. But after 3 stories were constructed, the ground began to unsettle.

When construction resumed, Giovanni di Simone (the engineer in charge of the project) attempted to make the new towers taller on the short side, but the extra weight worsened the lean. Efforts during the construction were continued, but the building eventually topped out in 1373.

Eventually, the lean became dangerous, and the building was approaching collapse during the 90s. So, a team was a assembled, and created a set of steps to solve this dangerous tilt.

First, counterweights were placed on the short side of the building, attempting to move the tower backwards and balance the two sides. The next step was to place harnesses on the building. Then, they dug wells under the foundation, and removed clay that softened the foundation. Also, they drained water from the base, which further stabilized the base. They then furthered the strengthening of the foundation by pouring concrete into the foundation. Finally, they straightened the building by pulling the aforementioned harnesses, and began to lessen the degree of tilt.

The stabilization of the Leaning Tower of Pisa did not fully straighten the building, but it was still a feat of engineering. This project is a testament to the work of geotechnical engineers, structural engineers, and physicists, and should be a lesson for aspiring civil engineers worldwide.