THE LEANING TOWER OF PISA : GEOTECHNICAL THEORY AND MODEL TESTS

Abstract

The leaning tower of Pisa is a famous historical structure, especially in the field of soil mechanics. In this paper, the historical development of the inclination is reconstructed considering that a ground failure took place after each of the three construction phases. Model tests (scale 1 : 130) were carried out in order to predict that the tower will fail definitely, i.e. without any further disturbances, at an angle of inclination of 5.7°, which is dramatically close to the actual value of 5.5°. The estimated probability of failure rises very quickly with an increase in the angle of inclination. Conservation of the tower should be done therefore with utmost caution.