Built to last in time, buildings have a lifecycle that may span over many centuries. During this period, they are restored, modified, expanded or demolished. Each of these interventions inevitably leaves traces, which are identified and arranged in a chronological sequence by building archaeologists in order to retrace the history of a building – or of its remains – from the moment in which it was built to present day. In the case of buildings stratification is mainly “vertical”, but its representation through GIS is “horizontal”. The study we propose was developed on the urban fabric of Pisa’s historical centre for the MAPPA project. The research started from a complete survey of the buildings, carried out using records that detailed the characteristics of the building through all the historical periods attested above ground, from Roman to Contemporary ages, allowing us to check the legibility and the transformations of the building structures. In order to collect the data, a database was created in which each record was defined on the basis of an Urban Architectural Unit (UAU) of belonging, i.e. an element that has its own identity and function in the present-day city. Every Unit is linked to the CAs (Architectural Building) and CFs (Construction) that eventually compose it. The former includes fields related to the name of the building, function, construction type, initial and final chronology and description of the building, the latter describes the function, construction type, and initial and final chronology. Both are linked to the Elevation Record and Building Phase Record. The former provides brief details and links to the drawn and photographic documents, whereas the latter describes each single construction phase in greater detail, through fields regarding construction materials, laying, building techniques, chronology, and description of brackets, putlog holes, supporting arches, portals and windows. A first novelty is the use of the webGIS to visualise the evidences: UAU, CA and CF feature classes are described with a polygonal graph, and phases with a linear graph. This allowed us not only to compare and crosscheck the data on a larger scale than traditional research, but also to obtain new elements on the way the city has grown, useful to define the archaeological potential of the various areas. The work carried out within the scope of the MAPPA project offers a second novelty which is currently at its start phase: building archaeology can provide data that are useful to determine buried artefacts. Specifically, they can reconstruct (at least from the late-medieval period) the original heights of the buildings and roads they overlooked, i.e. the height of the below ground level which has changed over the centuries due to the city’s increasing growth.

1. The representation of archaeological-
architectonical record of Pisa
Gabriele Gattiglia, MAPPA Lab – University of Pisa
Anichini Francesca, MAPPA Lab – University of Pisa
Mara Febbraro, Indipendent Researcher,
Fabiana Susini, University of Florence
Valerio Noti, TerreLogiche srl

2. MAPPA Lab is a research Lab of the University of Pisa,
which deals with:
• Predictive modeling
• Opendata
• Geo-archaeology
• Communication and storytelling
The representation of archaeological-architectonical record of Pisa

3. The representation of archaeological-architectonical record of Pisa
MAPPA Lab developed a predictive model based on
PageRank algorithm for the estimation of the
archaeological potential of an urban area.
Dubbini N., Gattiglia G, 2013
A PageRank based predictive model for the estimation of
the archaeological potential of an urban area
During this research project we used all the archaeological
data including building archaeology data, that we published
on an open access web map: the MAPPAgis
•Urban data
•Historical
cartography
data
•Geographical/
geomorpholog
ical data
•Archaeologic
al data
PRIMARY DATA
•obtained data
SECONDARY DATA

4. The representation of archaeological-architectonical record of Pisa
Anichini F., Gattiglia G. 2012 Some like it ‘webGIS’. Practical
indications for conscious archaeological use
Noti V. 2012 The MAPPA Project webGIS: system
architecture and future scenario

5. The representation of archaeological-architectonical record of Pisa
ground, from Roman
to Contemporary
ages, allowing us to
check the legibility
and the
transformations of
the building
structures.
The study was developed on the urban fabric of
Pisa’s historical centre for the MAPPA project.
The research started from a complete survey of
the buildings, carried out using records that
detailed the characteristics of the building
through all the historical periods attested above
Method

6. The representation of archaeological-architectonical record of Pisa
The building analysis was jointly carried out by
archaeologists and art historians allowing different methods
and skills to be shared
The building analysis was carried out on the basis of what
can be seen today, if a structure was attested at a certain
time in historical-literary sources, but traces of it could not be
seen in present day masonry, this “ghost” phase was not
taken into consideration in the GIS.
Information, however, was included in RDBMS.
A methodological choice such as this, which provides a
picture based solely on visible and objective evidence,
implies that, in the event of a search based on chronological
phases, empty spaces can be seen where we would expect
constructions on the basis of historical-archival-documentary
information.

7. The representation of archaeological-architectonical record of Pisa
Built to last in time, buildings have a lifecycle
that may span over many centuries.
Restorations, modifications, expansions or
demolitions leave traces, which are identifiable
in a “vertical”
stratigraphy, while
their GIS
representation is
“horizontal”.

8. The representation of archaeological-architectonical record of Pisa
In order to collect the data, the data model was defined on
the basis of an Urban Architectural Unit (UAU) of
belonging, i.e. an element that has its own identity and
function in the present-day city.
The buildings were identified using their name (if they had
one, for instance, historical buildings), their functional use (for
example, “hospital”, “court”, “school” etc.) or simply their
address.

9. The representation of archaeological-architectonical record of Pisa
Every Urban Architectural Unit (UAU) is linked
to
• Architectural Building (CA) (red)
• Construction (CF) (blue)
that eventually compose it.

10. The representation of archaeological-architectonical record of Pisa
In GIS:
• Urban Architectural Unit (UAU), Architectural Building
(CA) and Construction(CF) were described with a
polygonal graph,
• phases with a linear graph.
Identification of the primitives was based on the actual
consistency of the buildings: consequently, only the
polygonal graph was suitable for this description, given also
the project’s general coherence.
Instead, phases are represented by a linear graph for two
reasons: the masonry phase represents the result of an
interpretative process, whilst from a physical viewpoint it
represents the readable interface of the masonry stratification
to which a thickness cannot be assigned because in the
majority of cases the reading only refers to an external
interface and also because there may not necessarily be
exact correspondence between the interfaces placed on the
two sides of a masonry structure.

11. The representation of archaeological-architectonical record of Pisa

12. The representation of archaeological-architectonical record of Pisa
The photographic data are
suitable for recording the status of
conservation of buildings and their
decline (if any). It is a further tool
that helps gain knowledge of and
safeguard architectural heritage.

13. The representation of archaeological-architectonical record of Pisa
The data collected, which may be viewed on the
MappaGIS, are a starting point for defining the
transformation of Pisa’s urban fabric from the Late Middle
Ages to present day, in terms of construction systems,
types of buildings and urban planning.

14. The representation of archaeological-architectonical record of Pisa
The data produced by building analysis
permitted a better algorithmic representation of
archaeological potential of the various areas.

15. The representation of archaeological-architectonical record of Pisa
The next step will be to make the “ghost”
phases graphically visible. The aim is to make
information about Pisa’s buildings easily
accessible, distinguishing between what has
been preserved, even only minimally, and what
has been attested by written or iconographic
sources.

16. The representation of archaeological-architectonical record of Pisa
We tried to elaborate a language that could be understood
by whoever does not have experience of historical
reconstruction carried out from the viewpoint of building
stratigraphy.
There are no privileged recipients for this work; it is
directed to everyone: from novices to experts
(archaeologists, restorers, architects, engineers…),
including “technicians” who must take decisions regarding
urban planning and heritage protection.
Users can decide whether to stop at the initial information,
examine a single building in greater detail or view the
diachronic development of the city.
The webGIS platform produces new information (starting
from new data) about the characteristics of a specific urban
context with regard to construction systems, building
aggregations and stylistic features; in the future, it could be
useful for a 3D reconstruction of the historical centre during
its various building phases.
Conclusion

17. Thank you
Mappa Lab
info@mappaproject.org
Gabriele Gattiglia
gabriele.gattiglia@for.unipi.it
@g_gattiglia
http://pisa.academia.edu/GabrieleGattiglia
More info
@MappaProject
http://www.mappaproject.org
The representation of archaeological-architectonical record of Pisa