Understanding and Conserving Fortified and Difficult to Access Architectures through Digital Survey: A Case History in Southern Sicily

Introduction

The study presented is part of the current debate within the international scientific community aimed at the identification of rigorous methods of investigation able to define a suitable and innovative methodological approach based on the exploitation of ICT.

In particular, starting from the consolidated investigation methods, the research explores the criticalities linked to entrenched and difficult to access sites, complex structures in a state of ruin.

Often, the difficulties of access and the danger of the places have been an obstacle to the knowledge and documentation of this cultural heritage that is not studied and documented in a systematic manner and not receives adequate emphasis in the scientific literature.

The survey methodology that was applied provides an interdisciplinary approach aimed at documenting the structure in all its complexity and making use of current digital technologies at all stages of the learning process, which focuses on the role played by 3D model obtained through digital survey.

The study presented addresses the issues related to the knowledge and conservation of an important architectural episode, that is Mongialino's Tower (Mineo, Sicily), now in a state of ruin (see figure 1). The tower is unique in the panorama of fortified structures in Sicily and, perhaps, the European ones as well, for its inner cylindrical core that holds a tank.

Figure 1.

The tower of Mongialino rises on a rock promontory that dominates the valley of Margi

In this context, the digital survey, using a 3D Laser Scanner, has been essential to the knowledge and understanding of the severe state of decay and danger of the dungeon, as well as of the typological and constructive features. It is the most appropriate method for its conditions and provided a 3D model able to fulfill the investigations of the involved scholars.

The study, in fact, takes advantage of the obtained three-dimensional model in its being a digital replica of reality, objectively accurate, through which it is possible to identify the geometric rules as well as the classification of the materials and of the building techniques – both local and imported – in order to validate the historical-documental theory.

This digital model provides an accurate evaluation of the state of conservation of the dungeon and, the components of the building being known, the guidelines for an intervention plan for its conservation, which will be more coherent since there is the opportunity to carefully analyze the result, understanding its principles and the criteria which document the data acquisition process.

The paper is structured as follows: after a background on the state of the art of studies on fortified or difficult to access structures through digital surveying, the main core of the chapter will deal with the fortified site of Mongialino through a brief historical and territorial overview, the description of surveying and representation phases, the geometrical and proportional study and the typological and technological analysis; then the Future research directions and Conclusion will follow.

Background

As part of the geometric and architectural surveying of the cultural heritage, the disciplines of surveying have over time honed the techniques of data acquisition in step with the technological development that has answered frequent new instances of the scientific community. In fact, the instruments at the service of information and communication of knowledge increasingly evolve trying to meet the demands posed by new methods of investigation, both within the context of representation and communication.

For the knowledge and preservation of architectural heritage we make use of increasingly modern digital technologies for the purpose of a rigorous description and geometrical/morphological documentation for diagnostic analysis and design, as well as for the purposes of support to the visualization techniques and exploration and in virtual reality for the development of products in the field of tourism or recreation (semi-immersive virtual accessibility, enhancement and promotion of the site; simulation and evaluation of hypotheses for the conservation of the property, etc.).