3-Dimensional Geometric Survey and Structural Modelling of the Dome of Pisa Cathedral

Abstract

ABSTRACT:This paper aims to illustrate the preliminary results of a research project on the dome of Pisa Cathedral (Italy). The final objective of the present research is to achieve a deep understanding of the structural behaviour of the dome, through a detailed knowledge of its geometry and constituent materials, and by taking into account historical and architectural aspects as well. A reliable survey of the dome is the essential starting point for any further investigation and adequate structural modelling. Examination of the status quo on the surveys of the Cathedral dome shows that a detailed survey suitable for structural analysis is in fact lacking. For this reason, high-density and high-precision surveys have been planned, by considering that a different survey output is needed, according both to the type of structural model chosen and purposes to be achieved. Thus, both range-based (laser scanning) and image-based (3D Photogrammetry) survey methodologies have been used. This contribution introduces the first results concerning the shape of the dome derived from surveys. Furthermore, a comparison is made between such survey outputs and those available in the literature.

A Methodology for Planar Representation of Frescoed Oval Domes: Formulation and Testing on Pisa Cathedral

“…Currently, 3D architectural surveys mainly rely on two modeling methodologies-range-based and image-based [14]. The former exploits TLS to provide 3D point cloud models made of millions of points framed in a common reference system, which can represent the survey object geometry with subcentimeter accuracy [15].…”

“…Therefore, the oval is not exactly inscribed; instead, its layout is obtained through a tangency relationship solely affecting points E, F, G, and H (belonging to the oblique sides of the irregular octagon). The tangency in E, F, G, and H is accurately achieved, taking into account the constructive difficulties and irregularities due to deformations induced by phenomena of deterioration and subsidence of the foundation and elevated structures occurring over nine centuries of life of the building [14].…”

Survey, Experimental Tests and Mechanical Modeling of the Dome of Pisa Cathedral: A Multidisciplinary Study

“…It should be observed that, to the purposes of the present paper, a detailed survey has been necessary because of the absence of dome surveys characterized by high-density and precision. Without being exhaustive, the status quo on the surveys of the Cathedral dome, from the most ancient ones up today is briefly reviewed in [5].…”

A Multidisciplinary Approach for Historic Buildings Diagnosis: The Case Study of the Kaisariani Monastery

“…Currently, the scientific community tends to utilize both surveys, especially in cultural heritage documentation where the building materials play a pivotal role in the documentation process. In this case, both survey methods are elaborated and integrated, providing a textured 3D model [12][13][14][15].…”