Geotechnics and Heritage – Historic Towers

Uploaded At: 01 May 2024

The preservation of monuments and historic sites is one of the most challenging problems facing modern civilization because of the inextricable mix of different factors: cultural, humanistic, social, technical, economical, administrative.

The awareness of the role of Geotechnical Engineering in such a context moved Arrigo Croce and Jean Kerisel to propose the institution of an international Technical Committee on these topics. The ISSMFE, now ISSMGE, did establish in 1981 the TC19 – Preservation of Historic Sites; since 2001 the Committee has been renamed TC301 – Preservation of Monuments and Historic Sites. Initially, the Committee was supported jointly by the French and Italian National Geotechnical Societies; since 1989, by the Italian Society. It has been chaired by Jean Kerisel, Arrigo Croce, Ruggiero Jappelli, Carlo Viggiani and Renato Lancellotta.

The Committee organized two International Symposia on Geotechnical Engineering for the Preservation of Monuments and Historic Sites, both held in Napoli in 1996 and 2012. They were attended by over two hundred people presenting over one hundred papers, now collected in two nice volumes of Proceedings each totalling almost one thousand pages. TC301 has also published a special volume on Geotechnics and Heritage (2013) and promoted the Kerisel Lecture, held for the first time by Giovanni Calabresi at the XVIII ICSMGE in Paris, 2013.

Experience gained over the years proves the vulnerability of cultural heritage to a variety of geotechnical risks. This poses the problem of conceiving and implementing remedial measures preserving that immaterial value represented by the integrity of the single monument or the “diffuse cultural heritage”, that is the goal of any conservation intervention. In addition, it must be kept in mind that each monument or historic site is a “unicum” in itself, neither repeatable nor reproducible. It is then evident how difficult, or even to some extent dangerous, providing guidelines or recommendations with the aim of developing some sort of code of practice could be.

What is actually needed is a conceptual framework, based on a shared culture between geotechnical engineers and professionals as art historians, archaeologists, restorers, architects. This need has inspired the idea of relying on well-documented case histories as the most effective means to build a consolidated and shared lexicon and to highlight the basic principles by learning through real cases.

Such an idea lay at the heart of the publication by TC301, in 2013, of the special volume “Geotechnics and Heritage”; the present volume, “Geotechnics and Heritage: Historic Towers”, moves along the same path. In this case, well documented case histories of towers (i.e. slender structures transmitting high loads to the subsoil) of historic relevance that had or have geotechnical problems have been collected. The outcome presents an interesting picture of the variety of geotechnical problems that an historic tower may have to face in its life, and of the lack of unicity of solutions for the preservation actions to be implemented. Different solutions have been adopted in the reported case histories, reflecting also the existence of different cultural approaches to the topic around the world.

We hope that this undertaking will contribute to encourage geotechnical engineers to devote all possible efforts to the conservation of historic towers. All over the world, they are not only a distinctive feature of old towns and sites; representing a part that stands for the whole, they generate a deep consciousness of belonging to a community. A good reason to care about them and take good care of them.

The lovely picture on the cover of this book illustrates at the best the concept of ground-monument system; it seems to suggest that a majestic tree must be based on a similarly majestic underground structure. It is hence evident that geotechnical engineers may play a significant role in conservation. We hope that this volume will contribute to such an undertaking.

Geotechnics and Heritage: Historic Towers