Heritage is a consortium of whatever you can recount of in a place and what adds to a major fraction is what that stood tall defying the centuries. We owe it to preserving such creations and as it advances to ashes it is only 'rehabilitation' that creates a Phoenix out of it. This article explains how the Leaning Tower of St. Moritz (not Pisa!) challenged gravity and stood the test of time by embracing rehabilitation.
Having a tilt of about five times than that of the leaning tower of Pisa, The Leaning Tower of St. Moritz, Switzerland was constructed in the year 1570. The masonry tower was located alongside a hill with highly unstable soil conditions and therefore it was immensely affected by earth pressure resulting in a deviation angle of 20 degrees. The slope caused creeping constantly and even with continuous renovation, it proved to be ineffective.
It was only then hydraulic jacks came to the rescue. We have known the long standing applications of hydraulic jacks in the construction of high rise buildings, railways, highways, bridges, tunnels etc. Hydraulic jacks are incorporated in activities such as material handling and lifting, sliding, alignment and lining. However, post-construction benefits of Hydraulic jacks are immense and can work wonders. Hydraulic Jacks have thus made an advent in Civil Engineering.
So in the current case, the tilt of the tower was to be reduced so as to avoid further damage and collapse. It was decided to lower the hill side by 40 mm thereby modifying the Azimuth at that location. This was equivalent to reducing the deviation of the tower at the top up to about 160mm. This required a lot of external resistance to oppose the horizontal forces so as to partially correct the inclination. Therefore four Hydraulic Jacks were used with a total capacity of 8000 kN and placed on a guided sliding equipment to provide the necessary hindrance so that the inclination of the tower could be reduced and also to place the structure on a new foundation. Additional vertically installed jacks enabled the tower's position to be adjusted during the lowering works.
This made the Leaning Tower of St. Moritz not to be remembered through remnants but to be witnessed the way it ought to be.