Analysis of a site's integrity by 3D models and Integrated database, case study : the pic-du-midi high-mountain observatory (France)

TL;DR

This paper presents a method combining historical data, 3D modeling, and an integrated database to analyze the integrity of the Pic-du-Midi Observatory, accounting for its structural evolution over 150 years.

Contribution

It introduces a novel approach to integrity analysis by creating a series of 3D models and a database to document the site's evolution and current state.

Findings

Successfully modeled multiple reference states of the observatory.

Enhanced accuracy in integrity assessment through integrated historical and structural data.

Provided a digital tool for site management and future development.

Abstract

The concept of "integrity", as currently used in the analysis of World Heritage sites or cultural landscapes mainly consists of 1) the composition of a given site, regarding its origins and its current state of conservation; 2) the visual and functional relationships between its components (attributes). One of the major questions is "what defines the origin period?". The integrity analysis has to clearly understand and evaluate which tangible components exist, in order to correctly identify their origin period, estimate how much of the original structure and function remain. An additional difficulty rises in case of scientific and/or technical heritage assessment: the very historical necessity of updating and implementing technical/scientific innovations. These follow advances in science and/or technique(s), and lead to frequent successive changes, impacting the site's structure. Hence, for living sites, one cannot see the origin of the project as the only reference state, as it could be for classical heritage; it is instead requisite to enlighten a chronological series of major reference states. The Pic-du-Midi Observatory (France) is a remarkable example as high-mountain scientific station (2860 m). Its various and successive scientific uses led to a series of reshaping and structural evolutions over around 150 years, till nowadays. We have there a series of reference states very conform to an active scientific station and observatory. The project aims to combine historical data and measurements on the current site's state, to build a succession of 3D models for a series of 5 or 6 'reference state' of the observatory within associated database, and to document the integrity analysis more accurately than usual. The final uses of the digital achievement will also serve for the management of the site and for further development of