- The paper introduces a unified, tripartite 'Book' framework that harmonizes geotechnical data by separating factual data, model interpretation, and design synthesis.
- It demonstrates the effective use of the OGC SensorThings API and FROST Geotech Plugin to expose O&M-compliant geotechnical data via REST/JSON endpoints.
- The report emphasizes FAIR data principles and seamless BIM/GIS integration, paving the way for enhanced Digital Twin applications and risk assessment in infrastructure projects.
OGC Geotech Interoperability Experiment Engineering Report: A Technical Analysis
Overview and Context
The "OGC Geotech Interoperability Experiment Engineering Report" (2512.10678) documents a multi-institutional effort coordinated by the Open Geospatial Consortium (OGC) to harmonize the representation, exchange, and semantic interpretation of geotechnical investigation data. The report does not constitute an official standard; it is a deliverable from an interoperability initiative focused on aligning and federating domain models across major geotechnical, geological, and infrastructure modeling standards including OGC, buildingSMART International (bSI/IFC), AGS/AGSi, DIGGS, GeoSciML, and INSPIRE.
The core objective of this Interoperability Experiment (IE) is to establish a common conceptual model for geotechnical data that abstracts from serialization and application-specific concerns, enabling seamless integration and data federation across the geoscience, civil engineering, and infrastructure design domains. The report situates this work within broader efforts spanning Digital Twins, BIM/GIS integration, FAIR data sharing principles, and national/environmental spatial data infrastructures.
Conceptual Model and Standard Alignment
Model Structure and "Book" System
The conceptual schema underlying the IE is organized into a tripartite "Book" framework, derived from French tunneling best practices (AFTES recommendations):
- Book A: Factual Data—Capture of all “as-measured” observations, including borehole descriptions, in-situ tests, laboratory measurements, and environmental monitoring. Explicit adherence to the OGC Observations and Measurements (O&M, ISO 19156) meta-model ensures that all acts of observation, measurement, and sampling are rich in contextual metadata and adhere to a process-centric, temporally-aware data lifecycle.
- Book B: Models and Interpretation—Includes interpreted geoscientific/geotechnical models (geomodels, fault networks, hydrogeo-units, hazard models). These are formalized as composite features, each inheriting from base concepts in GeoSciML (for geology and structure), GroundWaterML2 (for hydrology), and extended for engineering-relevant units (e.g., geotechnical units as GeoSciML:GeologicUnit with
Type=GeotechnicalUnit).
- Book C: Design Synthesis and Risk Analysis—Connection of modeled conditions to engineering design elements, such as alignments, typical geotechnical sections, and risk zones. These are mapped into the OGC/IFC infrastructural schema (LandInfra, InfraGML, IFC Alignment), supporting linear referencing (ISO 19148) and explicit risk and hazard zoning (via INSPIRE Theme III).
Crosswalks and Realizations
Each geotechnical entity—borehole, trial pit, observation, material sample, model component—is explicitly mapped to (a) OGC Abstract Specification (e.g., O&M, Simple Features), (b) XML schemas and registries (GeoSciML, GroundWaterML2, AGS/DIGGS), and (c) JSON/REST-oriented implementations (OGC SensorThings API, STA).
Key technical features:
- Observation-centric metamodel: Observations are always contextualized acts, with traceable procedures, observed properties, features-of-interest, and reproducibility; direct linking to ISO 19156/OMS is mandatory.
- Linear Referencing: Integration of ISO 19148 permits unambiguous location referencing for 1D sampling features (e.g., along boreholes, trial pits), a recurring obstacle in cross-system data exchange.
- Multi-Standard Data Typing: Each concept (e.g., Borehole, FluidBody, Fault) is typed according to its realization in each reference standard, combined with property harmonization and semantic registry alignment.
- Soft-typing for Observations: While the conceptual model strictly distinguishes between observations and feature attributes, implementation mappings (notably AGS, DIGGS) are allowed flexibility (soft-typing) to accommodate domain practice.
Implementation, APIs, and Reference Architectures
OGC SensorThings API and the FROST Geotech Plugin
A central contribution of this IE is the demonstrated extensibility of the OGC SensorThings API (STA) for geotechnical borehole and field/lab test data. The FROST Geotech Plugin provides an implementation that directly exposes O&M-compliant geotech data over REST/JSON endpoints, enabling granular queries and automated federation of observations, sampling, trajectories, and associated metadata.
- Each borehole/collar and trajectory is represented as a "Thing" with associated linear referencing and geometry.
- Sampling activities, observations, sensors (i.e., test procedures), and observed properties are explicitly modeled as first-class entities.
- Advanced mapping supports in-situ and ex-situ acts, derived features (e.g., specimens, sub-samples), and relates observations to both their physical and procedural context.
Strong implementation results: Complex test types, including Cone Penetration Test (CPT), Standard Penetration Test (SPT), Menard Pressuremeter Test, and laboratory analyses (Atterberg Limits), have been demonstrated in detailed object diagrams and API usage examples. The system supports sophisticated queries for multi-dimensional data constituents (depth, position, property), grouping/filtering by semantics, and mapping to domain-specific classifications.
Semantic Interoperability and Controlled Vocabularies
Central to the interoperability architecture is the reliance on semantically controlled registries for procedures (observing procedures), observed properties, and units of measurement. The IE references and aligns with registries such as BRGM GeoScience Linked Data, DIGGS test/property dictionaries, Energistics UOM, and national classification vocabularies.
The report highlights the absence of globally harmonized code lists for all concepts, emphasizing the need for continued registry development and JSON-LD compatibility. It supports “semantic transposition”—the systematic projection of full observational metadata into simplified, analyst-ready structures (e.g., tabular download, reduced GeoJSON features).
Mapping to Existing Domain Standards: AGS, DIGGS, GeoSciML, IFC
The Engineering Report is explicit in the mappings between the new conceptual model and principal legacy and contemporary domain standards:
- AGS/DIGGS: Detailed guidance is provided for the translation of hierarchical CSV (AGS) and XML/GML (DIGGS) data structures into the semantically rich STA/O&M model, covering both in-situ and laboratory workflows.
- GeoSciML/GroundWaterML2: Physical and interpreted geotechnical/geoscientific entities use direct mappings to these standards, inheriting their extensibility and alignment with ISO/OGC best practices.
- IFC (Infrastructure and Civil): Integration is bi-directional; geotechnical extensions to IFC for tunnel/bridge/road infrastructure are articulated, and the report’s model is designed for compatibility with emerging IFC 4.3/4.4 schema.
- LandInfra and INSPIRE: Linear referencing, risk/hazard, and surrounding construction concepts are embedded and formally linked to these key standards.
Theoretical and Practical Implications
Theoretical:
- The report demonstrates the feasibility of comprehensive, process-aware, multi-standard ontologies for geotechnical data, aligning environmental monitoring, geoscientific modeling, civil engineering, and infrastructure informatics.
- It significantly advances the operationalization of FAIR principles in the AEC/geoscience domain, with explicit attention to semantic clarity, data contextualization, and interoperability at the procedural/observational level.
- The integration of linear referencing and observation-centric data lifecycle management resolves long-standing ambiguities in the representation and mapping of 1D/2D/3D physical sampling activities.
Practical:
- The FROST Geotech Plugin validates that rich, composable, and highly granular geotechnical data can be exchanged, federated, and queried in real-time using modern web-native protocols, supporting both domain experts and computational/statistical users.
- The approach admits the immediate integration of legacy data and infrastructure projects (via AGS/DIGGS), while enabling forward compatibility for advanced analysis and Digital Twin applications.
- Notably, the system preserves the full relational and procedural structure of measurements, supporting robust data provenance, QA/QC, and lifecycle analysis for engineering design, risk assessment, and environmental compliance.
Contradictory and Strong Claims
- The report specifically rejects the feasibility of using feature attributes alone for the representation of observation-driven data in geotechnics, mandating the adoption of the observation meta-model (O&M, ISO 19156) to ensure scientific validity and cross-domain interoperability.
- It asserts that seamless federation of BIM, GIS, and geoscience data is only achievable by embracing a model-federation paradigm where semantics, not physical implementation, dictate integration.
Future Directions
Identified Gaps and Next Steps
- Revisiting core reference standards (GeoSciML, GroundWaterML2) to harmonize with latest ISO O&M revisions and RESTful encoding practices.
- Extension of JSON-LD and tabular interfaces to facilitate semantic transformation and non-expert data usage.
- Broader support for 3D/4D geometries (Geo3DML, volumetric representation, voxel/Raster-as-feature), cross-sections, and advanced geophysical workflows.
- Expansion of semantic registries and direct linkage of geotechnical data APIs with knowledge graphs to support automated reasoning, quality assessment, and AI-based data analytics.
- Advancing the representation of activity/event provenance, particularly for complex, multi-phase engineering projects.
Conclusion
The OGC Geotech Interoperability Experiment Engineering Report (2512.10678) presents a rigorous, process-centric, and extensible framework for harmonizing geotechnical data across major domain standards. Its adoption of a federated, observation-based semantic model—unifying direct measurements, interpretive models, and design integration—enables robust, standards-based geotechnical data interoperability. The demonstrated API implementations and explicit mappings provide a validated path toward multi-domain, FAIR-compliant, and semantically interoperable geotechnical and infratech ecosystems. The report’s approach and technical artefacts are likely to inform future developments in geoscience informatics, infrastructure digitalization, and AI-driven civil/environmental engineering.
