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SURFACE SPATIAL ANALYSIS IN ARCHITECTURAL AND ARCHAEOLOGICAL SURVEY:
DIGITAL AND ANALYTICAL PROCEDURES
Raffaella BOLOGNA, Maurizio MINCHILLI
Dipartimento di Architettura ed Urbanistica
Politecnico di Bari
Via E. Orabona 4, 70125 Bari (ITALY)
minchilli@dau02.poliba.it
raf@dau02.poliba.it
Commission VI, Working Group 3
KEYWORDS: Analytical and digital photogrammetry, Architecture, Archaeology, Cultural_Heritage
ABSTRACT
The paper reports on some spatial analysis of ribbed vaults in Salento: the cloisters of Olivetani Monastery in
Lecce and of townhall in Manduria (Taranto). The ribbed vaults typical of Salento province (at the Est end of
Italy) are of great interest for architects for their variety and diversity in forms and assembling techniques.
These are some of numerous examples of photogrammetric analytical and digital spatial analysis worked out
in the last years. The tecniques of automatic image matching has demonstrated his own ripeness in
precision spatial correlation in conjunction with high digital images resolution. The metric photographs,
acquired with a 1400 dpi flatbed scanner, have been used to digital restitution, automatic D.E.M. generation
and orthoprojection in 1:10 scale of representation.
The surface analysis of the archaeological excavation, in the three naves of the Crociati hospital in Molfetta
(Bari) was carried out in 1997 and 1998 during the restoration works of the whole historical building. The
photogrammetric survey was justified by the need of detailed recording of the stratigraphy bottom and to
preserve the future reading of the pillars and walls foundations. Graphical restitution and the construction of
Digital Elevation Model were made by an analytical stereoplotter; the digital photographs were ortho projected
onto the numeric grid and then assembled together. This kind of representation is well appreciated by the
architects, for the restoration design, and by the historians for the immediateness of architectural reading.
1. MASONRY VAULTS IN THE LECCE
PROVINCE
1.1 Typology and construction
The vault roofing, built of freestone, materialises the
architectural space through the correct shaping of
stone ashlars and the subsequent spatial collocation
in structurally determined positions .
Nowadays in the Lecce province ( Salent is the
eastern portion of Italian peninsula ) the diffusion of
this structural typology in the historical buildings is
very high, with unchanged typological and
constructive characters, a sensible quantity of
dwelling rooms are constructed by craftsmen with
natural stone. Considering how big is the incidence
of manpower, in these small building yards, it’s easy
to conclude that there is an enormous interest for
architectural spaces strongly characterised by the
construction material: even with a notable reduction
of usability and functionality of such dwellings.
Those who have built and, still build, such types of
roofing ignore the theoretical principles of
construction science and our craftsmen did not
investigate the causes that bring to vaults instability
but simply observed the effects of instability on the
same vaults.
The subsoil of Puglia is mostly made of calcarenite
with surface layers of marine sediments result of
orogenic cycles. Apulian tufa and the leccese stone
belong to this category and are easy to carve with
simple tools. Being easy to model, this material is
suitable for constructions with ashlars of complex
shape both for vaults and arches. In several cases
the extraction of ashlars occurred directly in the
building yard, allowing to avoid the costs of
basement excavation and building materials
transport.
1.2 Shape study
The analysis of an object with a complex shape, as
that of the described architectures, requires
measure methodologies of medium-high accuracy
and easy applicability to various spaces and
volumes. Photogrammetic methods are suitable for
this kind of application, for their rapidity in the
execution of in situ operations, high accuracy and,
for what concerns digital photogrammetry, the
possibility of automatic image matching in an
oriented stereoscopic model.
The aim, not only practical, of the present study was
mainly to provide:
