1. Introduction

The Open Geospatial Consortium (OGC) is releasing this Call for Participation (CFP) to solicit proposals for the _OGC Geotech Interoperability Experiment (IE). This IE will assess the integration of geotechnical engineering data encoded in different specifications within Geospatial Information Systems (GIS) and Building Information Modeling (BIM) environments.

The goal of this IE is to ensure that geotechnical engineering data can seamlessly move between GIS and BIM environments to support engineering and infrastructure projects that rely upon those technologies. The IE will leverage OGC and buildingSMART International (bSI) Standards.

IE participants will produce an OGC Engineering Report (ER) that summarizes the activities of the IE, describes the suitability of the experiments for more broad use, and provides a description of gaps and further necessary experimentation, if any.

The IE will be coordinated with the Geoscience Domain Working Group (DWG) to review the ER and other IE outputs.

1.1. OGC Innovation Program Initiative

This initiative is being conducted under the OGC Innovation Program. This program provides a collaborative agile process for solving geospatial challenges. Organizations (sponsors and technology implementers) come together to solve problems, produce prototypes, develop demonstrations, provide best practices, and advance the future of standards. Since 1999 more than 100 initiatives have taken place.

IEs are generally structured to support or extend the standardization work in the OGC and thus the IE participants will coordinate closely with the appropriate OGC Technical Committee Working Groups, such as the Geoscience DWG mentioned above.

1.2. Contact

Answers to this Call are collected with the OGC Innovation Program contact form. Alternatively they can be sent to innovation@ogc.org.

2. Participants and observer organizations

This IE will be open to the general public. Participants will be required to make a resource commitment. Technical experts from non-OGC organizations may be Participants in the IE. Other individuals from non-OGC organizations will be allowed in the IE as Observers. Any OGC member may register as an Observer.

Participants and Observers will join the founding organizations of the IE. Founding organizations are:

  • MINnD (Modélisation des informations interopérables pour les infrastructures durables) National Project, France

  • Bureau de Recherches Géologiques et Minières (BRGM), France

2.1. Observer caveats

Official IE Observers will be granted access to the IE project on the OGC Portal. Observer status allows the member or non-member to monitor progress of the given IE, have access to the IE e-mail reflector, access documents as they are posted to the IE folder on the portal, contribute software and/or data to the effort, and so forth. Observer status does not allow the Member or non-member to attend the IE Kickoff meeting, formally comment on documents, or otherwise disrupt the execution of the IE. Interoperability Engineering Reports from the IE will be made available to all OGC members at the end of the IE for review and comment.

3. Scope of the IE

3.1. Overview

The extension of Industry Foundation Classes (IFCs; also approved by ISO and CEN as ISO 16739-1:2020) to geotechnics allows the description of semantic objects commonly used to observe and describe the environment of an infrastructure. Thanks to this advance, drawing and describing these geotechnical objects from a BIM tool and then sharing the information becomes possible.

However, in geotechnical engineering, much of the data is usually already available and described in other formats, particularly in some GIS format or encoded based on an OGC Standard such as GML. Having to re-enter the same data "for BIM" is both an effort and offers risk of error. Being able to use and read the data provided as an OGC encoding would thus constitute a significant gain for the user and would make the processing chain more fluid.

This project aims to propose a solution in this area and thus contribute to improving GIS - BIM continuity. Among other things, the project organizers aim to exploit the standardization resources already available from the OGC and other organizations as an input for OpenBIM resources. This work is illustrated by geotechnical data.

A proof of concept of this approach was completed and presented at the buildingSmart International Summit in Beijing in November 2019. The project described aims to build on this work and make this practice more standardized.

3.2. Objectives

The objectives of the IE include:

  • Align OGC and bSI conceptual models for geotechnical engineering and define possible calls to approved and in-development OGC APIs from bSI IFCs;

  • Consider the IFC extensions for infrastructure, especially the work done by IFC Tunnel for the description of geotechnics;

  • Extend existing OGC Standards for geoscience accordingly;

  • Draft a Technical Paper for coordinated management between OGC and bSI for geotechnical data management;

  • Draft technical documentation on the use of OGC APIs for this application domain; and

  • Draft implementation guidance for software publishers.

Fig1
Figure 1. General principle of GIS-BIM coupling proposed for geotechnical engineering including the possibility for an IFC file to reference properties provided by OGC APIs.

3.3. Background

Through the Integrated Digital Built Environment (IDBE) subcommittee, a joint group operated by OGC and bSI, membership in both organizations have worked together to identify common or supporting elements to be considered in their respective standardization activities. In January 2019, the IDBE subcommittee held a geotechnical data standardization workshop in Paris, France. Many recommendations from the workshop have contributed to the scope of this IE. In particular, the workshop attendees identified a need to interoperate with existing geotechnical data specifications: the Association of Geotechnical & Geoenvironmental Specialists (AGS) Data Format and the Geo-Institute Data Interchange for Geotechnical and Geoenvironmental Specialists (DIGGS) schema.

The MINnD National Project contributed to the identification for standards for geotechnics. For geotechnics, the project participants highlighted: * The existence of relevant standards that meet certain geotechnical requirements, notably from the OGC; and * The need to expand the scope of these Standards to cover additional requirements.

Actions are also underway to enhance the IFC format to exchange geotechnical data. However, the question arises of whether existing geotechnical data already available in GIS or Open GIS formats, particularly those based on OGC Standards, can be used.

4. Technical Approach

4.1. Alignment of OGC - bSI conceptual models for geotechnics

Semantics play a crucial role in the ability to understand data relationships. The use of known data models and controlled semantics is therefore the most important Interoperability criterion of the FAIR principles (https://www.go-fair.org/fair-principles/).

Started in 2020, the IFC Tunnel work has the goal of extending the IFC model to provide the capabilities to describe "geotechnical objects." The combined efforts of the MINnD Geotech WG1-5 and the IFC Tunnel Geotechnical Subgroup have identified existing OGC data models such as GeoSciML and GroundWaterML2. They also identified missing geotechnical concepts to serve underground infrastructure projects and existing IFC 4.3 data models.

Fig2
Figure 2. Semantics for geotechnical information

This alignment effort aims to enable the desired convergence between the two worlds as expressed in the IFC Tunnel Requirement Analysis Report. Members of the MINnD groups WG1-5 and WG1-4 contributed to this analysis and to the identification of the missing concepts.

This task will inform both bSI and OGC or how to best handle geotechnical data in their respective Standards, respectively with: * the bSI side accepting that existing OGC concepts be incorporated the IFC geotechnical proposal and that possible calls to current OGC APIs be defined; and * the proposed additions to IFC be included in the OGC models and that relevant OGC APIs be further developed to be inclusive of IFC content.

The focus of the action is on geoscience data, including both "factual" data as defined by Association Française des Tunnels et de l’Espace (AFTES) Book A and “model” data as defined by AFTES Book B.

Deliverable: Consolidation of a common conceptual model between OGC and bSI for geotechnics.

4.2. Extension of OGC standards

The OGC and International Union of Geological Sciences - Commission for the Management and Application of Geoscience Information (IUGS-CGI) have contributed to the definition of Standard data models for the geosciences, in particular GeoSciML and GroundWaterML2.

Although GeoSciML is focused on geology, its primary philosophy is to serve as a key encoding format for the geosciences information (hence its name). GroundWaterML2 is an extension of GeoSciML to specifically address hydrogeology, a science that uses geology and hydrology to describe groundwater. The extension of GeoSciML for geotechnics is in line with the original design objectives for this Standard.

The proposed actions in this task are to draft an extension package for the OGC geosciences Standards including: * Enrichment of existing GeoSciML concepts with properties useful to geotechnical engineering, as identified in the IFC Tunnel and MINnD GT1-5 projects; and * The addition and definition of new concepts and their attachment to existing concepts (extension of existing data models).

In concrete terms, the implementation of such technical actions leads to the following organizational actions: * The constitution of a working group (e.g., a new Standards Working Group (SWG) or an additional task for an existing SWG) to carry out the actions; * Organizing, leading, and reporting on coordination and progress meetings; * Setting up a platform for sharing the group’s production (e.g., GitHub); and * Informing and listening to other Working Groups that may be performing work related to this initiative.

Figure 4 shows the expected OGC-based standards concepts to be considered in this effort. Different fill and border colors highlight where these concepts fit into the geotechnical context. * Colored box without border: a concept from an existing model has been identified as a suitable basis for inclusion. It is expected that additional properties will be introduced to that concept. * Colored box with a border: a more generic concept exists. The specialization of that concept is necessary with inclusion of associated properties. * White box with dashed lines: this concept does not exist yet in an existing data model. The concept should be created (with associated properties) and connected to the existing data models.

Note that the topic of observations, measurements, tests, analysis, and interpretations (including geophysics) are all expected to be covered as part of the OGC Observations and Measurements Standard (also ISO 19156).