3D-STONE: A Workflow for Structured Light Scanning and Digital Twin Modeling of Stone Architectural Elements in Archaeology

3D-STONE: A WORKFLOW FOR STRUCTURED LIGHT SCANNING AND DIGITAL TWIN MODELING OF STONE ARCHITECTURAL ELEMENTS IN ARCHAEOLOGY Over the past decades, digital documentation has become a strategic priority in cultural heritage, offering enormous potential for archaeological research and conservation while mitigating physical degradation and expanding access to heritage. The rapid growth of 3D recording in archaeology has created an urgent need for standardized methods of data acquisition and management. Structured Light Scanning (SLS) has been successfully applied to various material classes to produce high-quality 3D models, yet it remains underutilized in the study of ancient architecture. To address this gap, the 3D-STONE workflow was developed within the CHANGES Project (CNR-ISPC) as a comprehensive methodology for applying SLS to stone architectural elements and processing their digital replicas. The workflow was tested using an Artec Eva scanner on marble blocks from the Basilica Iulia in the Roman Forum (Rome, Italy) and the Monumental Nymphaeum of Tripolis ad Maeandrum (Türkiye), addressing both archaeological challenges and technical-practical issues. This poster presents a summary of the workflow and its potential, as discussed in greater detail in BOZZA 2025. The complete step-by-step workflow is available on Zenodo.org (see QR code below). 1SARA BOZZA CNR - Istituto di Scienze del Patrimonio Culturale (Italy) [email protected] The 3D-STONE workflow encompasses all stages from field scanning to the final creation of 3D models. Tailored specifically for architectural blocks, it offers an efficient and reliable pipeline for digitization. It is divided into five main phases: The application of SLS to the stone architectural elements of the Basilica Iulia and the Monumental Nymphaeum allowed for the definition of optimal workflow procedures and 3D modeling parameters. Field Scanning Setup: Outdoor scanning required strategies to mitigate direct sunlight, which interferes with SLS tracking. A portable gazebo and black textile were used to create shade. Smaller blocks were scanned on a table to allow complete coverage, while larger ones were lifted using wooden supports. With this setup, a team of one operator and two assistants (for shading and block handling) could scan a block in 10-20 minutes, demonstrating the workflow’s efficiency. 3D Modeling with Artec Studio: The workflow uses Artec Eva’s HD mode,an AI-enhanced algorithm that produces noise-free, high-resolution models. From an archaeological perspective, HD mode was essential for capturing fine details –such as sharp edges and deep recesses –on complex elements like Ionic and Corinthian capitals, acanthus scroll friezes, and cornices. These included figured decorations, both “normal” acanthus and “fine-toothed” acanthus leaves, as well as unfinished pieces marked by drill holes outlining the decorative pattern. Compared to Standard mode, HD mode significantly reduced post-processing and accelerated the modeling pipeline. The final output is a high-resolution, accurate 3D model with realistic texture: a faithful digital twin that preserves the object’s geometry and surface features. Applying 3D-STONE to the marble blocks from both monuments demonstrated the effectiveness of SLS for documenting architectural heritage. SLS achieved exceptional accuracy in capturing geometry and surface texture –for both the well-preserved elements from the Nymphaeum and the heavily deteriorated ones from the Basilica. Moreover, the workflow greatly reduced fieldwork and processing time compared to photogrammetry-based approaches. This efficiency is particularly valuable when documenting hundreds of blocks, reinforcing the utility of SLS for large-scale architectural studies. Beyond their visual quality, the 3D models are powerful tools for research and dissemination. They can be used in virtual reconstructions to test hypotheses about the monument’s original layout. Researchers can conduct detailed morphological analyses and perform state-of-conservation mapping directly on the digital models. Additionally, these 3D replicas support public engagement via interactive visualizations and 3D-printed reproductions, helping diverse audiences to better understand the monument’s architecture. The potential of the 3D-STONE workflow within broader architectural research is exemplified by the ongoing Basilica Iulia Project (GALLI, ISMAELLI 2022; DEMETRESCU et al.2025). The standing remains were recorded using photogrammetry and laser scanning to produce a georeferenced digital replica, while detached architectural blocks were cataloged and digitized using 3D-STONE. Through the Extended Matrix approach (https://www.extendedmatrix.org), the Basilica’s digital twin serves as a3D repository for data archiving and interpretation. It ensures transparency in both the raw data and the reconstruction hypotheses. Each scanned block acts as a digital proxy of its physical counterpart, used in astone-by-stone virtual assembly of the monument. This approach is both a research tool and an innovative communication method: users can explore the reconstructed Basilica, isolate individual components, and access detailed information –ensuring transparency of the interpretive process. Basilica Iulia: general view (a) and cataloging work (b). Monumental Nymphaeum: scanning the blocks on a table in the depo (c) and under the gazebo on the field (d). INTRODUCTION 3D-STONE WORKFLOW IN BRIEF EXPERIMENTATION RESULTS: ARCHAEOLOGICAL / PRACTICAL QUESTIONS Monumental Nymphaeum, testing the potential of HD mode in Artec Studio: figured capital (a) in HD (b) and Standard (c) mode; a leaf of a Corinthian capital (d) in Standard mode, during cleaning of artifacts in the eyelets (e) and in HD mode (f); unfinished acanthus leaves of a pseudo-Corinthian capital (g) in Standard (h) and HD mode (i). Basilica Iulia, the digital replica of the monument as 3D repository of research data: Doric capital no. 211036 linked to the Extended Matrix through which the related documentation can be accessed: photograph from 1898, catalog record, 3D model from structured light scanning. APPLICATIONS OF 3D-STONE CASE STUDY: VIRTUAL RECONSTRUCTION OF THE BASILICA IULIA 1 Setting preparation and organization of the scanning team: Setting up the scanning environment (e.g., ensuring adequate shade) and coordinating tasks (e.g., positioning blocks). 2 Scanning with Artec Eva and tablet: Capturing each object with a handheld Artec Eva scanner connected to a tablet for maximum on-site mobility. 3 Modeling with Artec Studio: Processing scan data in Artec Studio on a high-performance workstation to produce detailed models. 4 Orientation of the digital replica: Aligning the model’s faces within the reference coordinate system to reflect the physical orientation of the object. 5 Export in OBJ format: Delivering a highresolution, textured model in OBJ format, suitable for analysis, visualization, and archiving. Bibliographical references BOZZA S. 2025 3D-Stone: A Comprehensive Workflow for Structured Light Scanning and Digital Twin Modeling of Stone Architectural Elements in Archaeology,in ACalc,in press. DEMETRESCU E. et al.2025 The collaborative Basilica Iulia Project: A Digital Knowledge Ecosystem for Integrated Archaeological Research, in Digital Heritage,in press. GALLI M., ISMAELLI T. 2022 Basilica Iulia I. Gli scavi di Laura Fabbrini (1960-1964): strutture, stratigrafie e materiali dalla prima età repubblicana alla costruzione Augustea, Istanbul. a b c d a b c d e f g hi