Towards a digital approach of preventive conservation: Evaluation of geometric deformations for antique funerary monuments in Algeria by digital twins (TLS) and remote sensing (Case study: Lambeze Mausoleum (Batna) and Bordj Choumissa Mausoleum (BBA)).

Abstract

The built Heritage structures of the antique period are increasingly threatened by natural, anthropogenic, and temporal factors. The traditional strategies of conservation and documentation remain insufficient to safeguard this legacy. This research aims to introduce a new approach to preventive conservation capable of documenting and evaluating the mechanical behavior and rigidity of this architecture under differing environmental conditions, using advanced remote sensing and digital modelling methods, we propose an analytical protocol combining terrestrial laser scanning (TLS), AI-assisted detection, and digital twin (DT) modelling all at once. The Dynamic model is constructed by integrating historical archival plans with high-resolution point clouds from TLS. We apply this protocol to two mausoleums of similar form: Bordj Choumissa (Bordj Bou Arreridj) and Lambeze (Batna). The mausoleums are exposed to very different weather conditions. Cross-sectional analysis measures internal deformations along main axes, while best-fit (BF) fitting is used to detect cracks and identify structurally vulnerable areas by assessing surface flatness and stability. The results, shown by scalar fields and deformation diagrams, show that structural changes can be measured and are linked to environmental factors. The differences between the two sites show how climatic variations can affect the stability of monuments. This methodology permits differentiated diagnosis, risk mapping, and simulation of restoration scenarios. The study contributes a scientific remote‐sensing‐based foundation for preventive conservation and informed planning of interventions on built heritage.

Keywords

• Diagnosis
• Remote sensing
• Digital twins
• Preventive conservation
• Funerary heritage

Ethical Statement

The authors declare that there is no conflict of interest.

Thanks

The authors would like to thank the laboratory of Mediterranean Architecture for providing the necessary equipment and technical support required for this research. The authors also express their sincere gratitude to the National Office for the Management and Exploitation of Protected Cultural Properties for authorizing and facilitating access to the studied archaeological sites and monuments.

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