Maria Teresa BARTOLI
(University of Florence, Dept. of Architectura, Italy)

Keywords: CAD and ancient building knowledge, nexus between the Abaco science and medieval architecture, making up immaterial aspects of ancient buildings shape

Palazzo Vecchio in Florence is not an archaeological monument but a well preserved Medieval building; yet, like other contemporary monuments, its plan and its volumes embarrass historians of architecture,  who consider  the features of its shape too distant from  their expectations.  They are not able to recognize the irregular form of its strange perimeter as the result of an intentional design, and ascribe it to external causes, like underground walls of pre-existent structures. A significant part of the monument logic (immaterial heritage in a material monument) has become an archaeological matter: we have lost the memory of intentions and meanings linked to its peculiar shape.
Methodology: CAD representation of the survey of the palace in two-dimensional drawings leads to different results and to the discovery of unknown aspects of the plan. CAD drawings can be converted so that we can read the building’s measures according to its metrical system and have a notion of the possible sense of its layout.
Result: If the length and square measures of a place are known, the peculiar shape of a plan can reveal an unforeseen sense. The whole metrical Florentine system of linear and surface measures enlightens the extraordinary design, where the areas of its three parts (easy to calculate with CAD, almost impossible before CAD, owing to the irregular form of the perimeter) stress the fact that the goal of each portion’s design was the rational expression of the area, by means of integers joined to specific square measure. The geometrical process of the drawing comes out as an original creation.
Innovation: Through this analysis unexpected results have been reached about Palazzo Vecchio. Cad drawings bring to light unknown relations, ignored by literary sources, between architecture and new scientific science in Tuscany at the end of thirteenth century (after Leonardo Pisano’s work), as a specific immaterial ratio of the monument, impossible to be found without the simple, but not trivial, instruments offered by CAD.