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Authenticity of Foundations for Heritage Structures
Authenticité des fondations pour les structures du patrimoine
Iwasaki Y.
Geo Research Institute, Osaka, Japan
Zhussupbekov A., Issina A.
Eurasian National University, Astana, Kazakhstan
ABSTRACT: Foundation system is a basic part to support structure of cultural heritage but has been considered only as a function to
keep authenticity of the heritage upper structure. Recent trend has changed the situation. Foundation becomes to be considered as an
important part of structure and sometimes to be evaluated as an element of authenticity of heritage based upon unique characteristic in
region as well as of the period that the heritage belongs. This paper describes a short history of authenticity of cultural heritage and
discuss several examples of the authenticity of foundation systems including leaning Pisa Tower, stone masonry in Angkor,
Cambodia, and wooden pile foundation of Great Gate at Itsukushima shrine, Hiroshima, Japan.
RÉSUMÉ : Le système de fondation est un élément fondamental pour soutenir la structure du patrimoine culturel mais il ne lui a été
longtemps considéré comme une fonction que de garder l'authenticité de la structure patrimoniale supérieure. La tendance récente a
changé la situation. La fondation devient un élément important de la structure elle-même et est parfois tenue comme un élément de
l'authenticité du patrimoine basé sur une caractéristique régionale unique ainsi que sur la période à laquelle appartient le patrimoine.
Cet document décrit un bref historique de l'authenticité du patrimoine culturel et discute de l'authenticité de plusieurs exemples de
systèmes de fondation, tels que la Tour Penchée de Pise, la maçonnerie en pierres à Angkor au Cambodge, et les fondations sur pieux
en bois de le Grande Porte à Itsukushima, Hiroshima, au Japon.
KEYWORDS: cultural heritage, authenticity, foundation, Pisa Tower, Angkor, Itsukushima shrine
1 INTRODUCTION
Geotechnical engineering plays one of the important role to
safeguarding cultural heritages and has made such key
contribution as in restoration work for the inclined Pisa Tower.
However, foundations are generally considered as simply
nothing but to support the heritage sturctures and not considered
as a part of the heritage.
However recent trend of conservation of heritage indicates
foundation system has become to be considered as one of the
basic components of the heritage structure. Recent renewal of
an international standard of ISO 13822 on assesment of
structural safety added an Annex “Heritage Structures” and
stressed the importance of the foundation.
In this paper, the new concept of “authenticity of
foundation” is discuused as well as the characteristic elements
of authenticity that should be evaluated and restored.
2 AUTHENTICITY
Authenticity was defined in the Venice Charter of 1964 as
heritage composed from original material, original position,
original design as well as original procedure. The comcept of
the Venice Chapter is called “anastylosis(Greek),” which means
“take column back to original position.” Anastylosis implies
that original stone columns spread over in a historical ruin shall
be rebuilt at the original positions. Anastylosis does not give
any values of heritage to such repaired materials as often seen in
wooden structures in Japan. The principle of the anastylosis was
developed along the base of conservation of stone structure in
Europe and resulted in the Venice Chapter.
Later in 1994, the concept of the authenticity was expanded
by the Nara Document on Authenticity to cover various
methods characterized by region to which the heritage belongs.
Region specific method that developed in some area is also
accepted as the characteristic of authenticity.
Character-defining elements are defined as historic materials,
forms, locations, spatial configurations, morphology, concept
and details, structural design, uses, and cultural associations that
contribute to the heritage value of a structure that shall be
retained in order to preserve its heritage value
3 AUTHENTICITY OF FOUNDATION
In 2005, ISO 13822(Bases for design of structures –
Assessment of existing structures) was reviewed for renewal.
ISCARSAH(International Scientific Committee on the Analysis
and Restoration of Structures of Architectural Heritage under
ICOMOS) had proposed to include heritage structures in the
standard and worked together for five years. The ISO 13822 has
been updated in 2010, and added an Annex-I (informative)
Heritage Structure, which has expanded the heritage structure to
include foundation as a part of the structures.
The Annex I clearly states as in a paragraph of I.5.3
Authenticity of foundation that “ From the point of view of
conservation, foundations are not different from the rest of the
structure and should be assessed and rehabilitated taking into
consideration their heritage value. This involves the requirement
to identify their authenticity and character-defining elements.”
3.1 Leaning Tower of Pisa
The inclined Pisa Tower was registered in 1987 as World
Heritage by UNESCO.
The construction of the tower started in 1173 and completed
in 1372 on a thick soft clayey ground in northern Italy as shown
in Figure 1. In 1970’, Italian government called for internaional
competetion of proposal to remedy and to restore the monument
but did not carry out due to finacial shortage. In 1990’,
international committee was organized to discuss the restoration
how to conserve the inclined state of the upper structure of of
the tower as it was. After heated discussions, a method to
