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Towards a Decentralised Common Data Environment using Linked Building Data and the Solid Ecosystem

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With the emergence of Building Information Modelling (BIM), the construction industry is rapidly catching up with the digital revolution that has boosted productivity in virtually all economic sectors. In current practice, the focus of BIM lies on exchange of documents, often through proprietary formats exchanged using the Industry Foundation Classes (IFC). However, with web technologies such as RDF, OWL and SPARQL, a data-and web-based BIM paradigm becomes within reach. The decentralisation of data and decoupling of information and applications will enhance a more general adoption of Big Open BIM, and is expected to lower the BIM threshold for smaller companies that are active in different phases of the building life cycle. Since one of the promises of the Semantic Web and Linked Data is a highly improved interoperability between different disciplines, it is not necessary to reinvent the wheel for the setup of an infrastructure that supports such a network of decentralised tools and data. In this paper, we evaluate the specifications provided by the Solid project (Inrupt Inc.), a Linked Data-based ecosystem for Social Linked Data. Although the exemplary use case of the Solid ecosystem is decentralisation of data and applications for social network purposes, we notice a considerable overlap with recent ambitions and challenges for a web-based AECO industry (Architecture, Engineering, Construction and Operation). This includes standardised data representations, role-or actor-based authorisation and authentication and the need for modular and extensible applications, dedicated to a specific use case. After a brief introduction to Linked Data and its applications in the building industry, we discuss present solutions for building data management (Common Data Environments, multi-models, etc.). In order to translate these approaches towards a Linked Data context with minimal effort and maximal effect, we then review the Solid specifications for use in a construction-oriented web ecosystem. As a proof of concept, we discuss the setup of a web-service for creation and management of Linked Building Data, generated with the Solid-React generator. This application is envisaged as a bridge between the multiple data stores of different project stakeholders and the end user. It acts as an interface to a distributed Common Data Environment that also allows the generation of multi-models.
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1
Towards a Decentralised Common Data Environment using
Linked Building Data and the Solid Ecosystem
Jeroen Werbrouck*,
Ghent University, RWTH Aachen University
(jeroen.werbrouck@ugent.be)
Pieter Pauwels,
Ghent University
Jakob Beetz,
RWTH Aachen University
Léon van Berlo,
Netherlands organisation for applied scientific research TNO
Abstract
With the emergence of Building Information Modelling (BIM), the construction industry is rapidly
catching up with the digital revolution that has boosted productivity in virtually all economic sectors.
In current practice, the focus of BIM lies on exchange of documents, often through proprietary formats
exchanged using the Industry Foundation Classes (IFC). However, with web technologies such as RDF,
OWL and SPARQL, a data- and web-based BIM paradigm becomes within reach. The decentralisation
of data and decoupling of information and applications will enhance a more general adoption of Big
Open BIM, and is expected to lower the BIM threshold for smaller companies that are active in different
phases of the building life cycle. Since one of the promises of the Semantic Web and Linked Data is a
highly improved interoperability between different disciplines, it is not necessary to reinvent the wheel
for the setup of an infrastructure that supports such a network of decentralised tools and data. In this
paper, we evaluate the specifications provided by the Solid project (Inrupt Inc.), a Linked Data-based
ecosystem for Social Linked Data. Although the exemplary use case of the Solid ecosystem is
decentralisation of data and applications for social network purposes, we notice a considerable overlap
with recent ambitions and challenges for a web-based AECO industry (Architecture, Engineering,
Construction and Operation). This includes standardised data representations, role- or actor-based
authorisation and authentication and the need for modular and extensible applications, dedicated to a
specific use case. After a brief introduction to Linked Data and its applications in the building industry,
we discuss present solutions for building data management (Common Data Environments, multi-
models, etc.). In order to translate these approaches towards a Linked Data context with minimal effort
and maximal effect, we then review the Solid specifications for use in a construction-oriented web
ecosystem. As a proof of concept, we discuss the setup of a web-service for creation and management
of Linked Building Data, generated with the Solid-React generator. This application is envisaged as a
bridge between the multiple data stores of different project stakeholders and the end user. It acts as an
interface to a distributed Common Data Environment that also allows the generation of multi-models.
Keywords: Linked Building Data, Common Data Environments, Decentralisation, Solid
1. Introduction
The building industry is one of the most fragmented industries around the world. At the same time, it is
also among the least digitised ones, only leaving Agriculture and Hunting behind (McKinsey &
Company, 2015). Although the recent upcoming of Building Information Modelling (BIM) has
2
somewhat closed the gap, multiple challenges still need to be overcome before the sector reaches the
full potential offered by digitisation. In other words, the use of integrated, interoperable data, exchanged
through connected web services, or the reaching of BIM Maturity Level 3as defined in the notorious
BIM wedge (Fig. 1). The main goal of web-based BIM is to provide an answer to data islands that
complicate lossless exchange and collaboration between disciplines that focus on the built environment.
These disciplines form the AECO industry (Architecture, Engineering, Construction and Operation).
Figure 1: The BIM levels of Maturity as defined by BSI Standards Limited, 2013
Linked Data technologies are considered very promising to reach such high level of interoperability.
These technologies rely on the Resource Description Framework (RDF)1, which is a data model that
has been standardised as part of the Semantic Web technology stack (Berners-Lee, Hendler, & Lassila,
2001). Using RDF, individual data concepts can be linked to one another in the form of triples. RDF
triples can be understood as very basic sentences, linking a subject to an object with help of a predicate
that states the exact relationship between the two. To ensure that each data item is uniquely identifiable
over the web, it is characterised by a Uniform Resource Identifier (URI). This strategy, which is the
main difference between RDF and other existing data models, allows to semantically enrich information
in an open-world way: anything can be said about anything, which opens up possibilities for
interdisciplinary collaboration. Furthermore, due to the structured representation of data in the form of
a web-wide graph, digital agents are capable of semantically interpreting this data and using it for
specific purposes with minimal human intervention. A distinction can be made between the terminology
that is used to describe data (e.g. a taxonomy, a type) and the actual data individuals that are semantically
connected using these structures (e.g. a specific object). The former is referred to as the TBOX
(‘Terminological’), the latter as the ABOX (‘Assertion’). Knowledge models for defining conceptual
domain schemas are mostly on a TBOX level. Such schemas are called ‘vocabularies’ or ‘ontologies’2
and give semantic meaning to certain data elements. The combination of multiple vocabularies allows
to set up complex models of real problems.
The application of Linked Data concepts for the AECO Industry has been documented multiple times
by now (Beetz, Van Leeuwen, & De Vries, 2005; Pauwels & Terkaj, 2016; Pauwels, Zhang, & Lee,
2017; Rasmussen et al., 2017), because it could seriously enhance interoperability between disciplines
and collaboration between stakeholders. Linked Data allows to construct vocabularies for each related
sub-discipline, connected with one another in a neutral format and distributed over multiple servers.
1 https://www.w3.org/TR/rdf11-concepts/, W3C
2 https://www.w3.org/standards/semanticweb/ontology.html, W3C
3
This allows applications that are concerned with different aspects of the built environment to connect
and exchange information without information loss. It also allows to link to open data on the web, such
as contextual information (e.g. geospatial, governmental, historical or weather data). Furthermore, since
vocabularies contain the information to interpret the data in a semantic way, automatic reasoning and
rule checking comes within reach (Pauwels et al., 2017). With this in mind, several researchers are
currently working on making Linked Data-based BIM more mature. First proposed in (Beetz et al.,
2005), the setup of a Linked Data-based version of IFC was officially approved as the ifcOWL ontology
(Pauwels & Terkaj, 2016). However, as ifcOWL covers the entire IFC schema, it is very large and
consequentially not really flexible to deal with topics that are not sufficiently covered in the IFC
standard, such as existing buildings, Geographic Information Systems (GIS), Facility Management
(FM) or circular economy. A new paradigm is therefore proposed by the W3C Linked Building Data
Working Group3, targeting the development of more modular vocabularies that each address a specific
building-related topic (Rasmussen et al., 2017). The main advantage of such modular Linked Data
vocabularies over traditional, monolithic, domain-specific information models such as the IFC schemas
is their modularity, which increases the flexibility to address specific challenges.
While much research and standardisation has been done regarding the Semantic Web, in general as well
as for construction, the number of applications that effectively use its potential remains limited: Linked
Data technologies have a steep learning curve and there is quite an implementation threshold for
developers to actively contribute to an interconnected network of online applications (Verborgh, 2018).
In order to stimulate the worldwide developer community, and to separate personal data from the
applications that use it, the recent Solid project (Social Linked Data) was founded (Mansour et al.,
2016). It aims at a decentralised ecosystem for social web applications, in which users own their data
themselves and allow external (micro)applications to use it for a certain (social media) purpose.
However, social media are just one use case picked by the Solid team to illustrate its concept. The same
set of specifications and tools can be used for other domains as well, especially for disciplines as
fragmented and decentral as the construction industry.
Multiple research projects are focusing on the development of knowledge models for describing the
built environment in a Semantic Web context. In order to implement these knowledge models and move
towards BIM Maturity Level 3, usable applications need to be developed. Modular web applications
for the building industry, able to communicate with each other and exchange disparate data with use of
HTTP and JSON, were recently re-introduced as ‘BIM bots’4, often built using the BIM bot compliant
BIMserver framework (Beetz, van Berlo, de Laat, & van den Helm, 2010), a well-known
implementation of Model Servers that is based on IFC. Going one step further, the idea of BIM bots
could be extended with Linked Data, broadening their range towards topics that are not typically
covered by IFC. As the Semantic Web technology stack offers the possibility to connect various
domains, there is no need to start a specific Linked Data ecosystem for construction. With this in mind,
this paper discusses the use of the specifications provided by the Solid project. As we consider a way
for collaborative project data management the first step for a network of Linked Building Data tools, a
prototypical management service is implemented within the Solid ecosystem as proof of concept, using
the Solid-React generator, which hides the complexity of authentication, authorisation, data storage etc.
2. Collaboration strategies for building projects
Different strategies exist by now to reach a more streamlined collaboration within building projects. A
Common Data Environment (CDE) is a virtual storage location for collecting and managing
documentation of building projects, mostly offered as a cloud service. Because all project information
is managed in this common environment, the chance of misunderstanding and information loss is
strongly reduced. Access to certain documents can be defined by the project’s Information Delivery
Manual (IDM), based on the international BuildingSMART standard for bundling and structuring
3 https://w3.org/community/lbd/, Linked Building Data Community Group
4 http://bimbots.org/, Van Berlo, L.
4
Information Requirements (IR). Examples of commercial CDEs are, for instance, Autodesk’s BIM 360
and Trimble Connect. CDEs can be optimised to work with certain data formats, either proprietary or
open. Standards such as IFC allow information to be exchanged between applications from different
software vendors, which, in most cases, use proprietary data formats natively. The BIMserver platform
(bimserver.org) implements IFC in a model server and allows developers to build web services or
plugins that can be connected to the shared IFC database and exchange data via a common API (e.g.
BIMSie (van Berlo, 2015)). Recent developments show that the main CDE suppliers are open to develop
a standardised open API for CDEs. This initiative just recently started as a follow up from the German
DIN SPEC (91391-1/2) initiative that defines the features and expectations from a CDE.
An approach related to CDEs, but more focused on the container structure in which project information
can be stored, are the so-called multi-models. The most recent development in this domain is the
Information Container for Data Drop (ICDD), which is in the final stage of standardisation as ISO
21597. It is the successor of the Dutch COINS standard and follows a tradition of ontology-based multi-
model management (Gürtler, Baumgärtel, & Scherer, 2015; Schapke, Katranuschkov, & Scherer, 2010;
Törmä, 2013). In its own words, ICDD has been developed in response to the need of the construction
industry to handle multiple documents as one information delivery or data drop’. Its internal structure
is based on two ontologies: a Container ontology and a Linkset ontology. As the former defines the
classes and properties used for description of metadata about the container, the latter provides the
definitions for the semantic links between documents. The standard allows to refer to identifiers on a
sub-document level, such as individual IFC GUIDs or pixel zones within an image. An ICDD container
can be considered a semantically connected ‘dump’ folder with the available project information, and
can, for example, be used when project data needs to be transferred from one project stakeholder to
another. A container in *.iccd format (using a ZIP compression) has a fixed structure, containing
subfolders with the main ontologies, the ‘payload documents’ (e.g. imagery and IFC files) and the
‘payload triples’ for the relationships between those documents. The main folder contains an index.rdf
file that contains the documents of the project and some metadata. The content.rdf file that is stored in
the ‘payload triples’ folder can also refer to external documents or URIs. An overview of the ICDD
structure is given in Fig. 2, depicting the folder structure and a subset of a linkset in Turtle format.
Figure 2: Structure of an ICDD container (source: ISO 21597-1)
In this section, a brief introduction was given to CDEs and the ICDD standard for multi-model
containers. While CDEs focus on a cloud environment for enhanced collaboration, Linked Data-based
multi-models allow to establish specific links between project documents and sub-document
information. A Linked Data-based CDE would need to combine the possibilities offered by CDEs, while
allowing to establish links between RDF data and documents, on a fine-grained data level. This way,
project sources such as imagery, point clouds, geometry etc. can be linked with RDF graphs about
topology, products and properties. In the next section, we review the specifications of the Solid
ecosystem for use in such a Linked Data-based CDE.
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3. Solid specifications
The initial use case of the Solid ecosystem is social media. Decoupling of applications and data lets
users stay the owner of their own data and allow the applications that suit their needs the most to access
that data. From a more general perspective, it embodies a movement that aims to realise the web ‘as
originally envisaged’ by Tim Berners Lee (Berners-Lee, Dimitroyannis, Mallinckrodt, & McKay, 1994;
Berners-Lee et al., 2001): personal data storage, standard communication between apps and the use of
a universaldata format in the form of RDF5. The decoupling of apps and data is as relevant for the
building sector as it is for social data. The BIMserver realises this within context of IFC; the Solid
framework could be a candidate for doing this in a Linked Data context. In the following section, we
review the main specifications for the Solid framework6, and suggest how they could be implemented
for projects dealing with the built environment.
3.1 Identification and authentication
In Solid, identification of actors happens through WebIDs7. In Section 1, it was stated that in Linked
Data, every ‘resource’ is identified through a unique identifier over the web, a URI. Applied to WebIDs,
this means that any actor can have their own URI, that can relate to other resources (e.g. personal data
or other people’s WebIDs) and be linked to by other resources as well. This generates a global ‘social
graph’ with fundamental relationships between a person, his data and other people’s data. Within Solid,
the WebID is used as a URL (Uniform Resource Locator), which is a specific type of URI that, apart
from identifying the resource, also allows to access it. An example of a WebID could be
https://jwerbrouck.solid.community/profile/card#me. It identifies both the resource that should be
included in triples that link to this person, and the web address that allows to access his personal data
card. This card is part of the ‘datapod’ of the actor: the server (personal or hosted by a providers) that
contains an inbox, a public folder and a private folder. According to the specifications, a 2019 update
will include a section where access rights for third-party applications can be managed: read, write,
append and control. At the time of writing, this is only managed by logging in to the application with
the personal webID. This system of datapods that allow specific apps to access the data is the main
difference with current social networks, that require users to upload their data. The WebID also serves
as the basis for authentication of actors, instead of usernames, by making use of the WebID-TLS
protocol8 and cryptographic certificates generated by the browser.
3.2 Authorisation
To determine whether a certain actor (person or application) has access to particular data, an RDF-based
authorisation mechanism called ‘Web Access Control’ (WAC) (Hollenbach, Presbrey, & Berners-Lee,
2009) is used. Actors can be identified by their WebIDs, which are stored in *.acl graphs that state
which webIDs should be allowed to read or update data. The specification also allows to refer to groups
of users instead of specific ones. An *.acl file can be linked to an entire folder (such as the basic folders
for public and private data), but can also be mapped in a more fine-grained way to subfolders or
individual files or RDF graphs. Currently, the specification does not allow for mapping on resource
level, which could be beneficial for Linked Data-based building projects (Oraskari & Törmä, 2016).
3.3 Content Representation
In general, datapods make a difference between Linked Data resources (e.g. in the form of Turtle,
JSON-LD, etc.) and non-Linked Data resources (e.g. imagery, PDF files, etc.). All the resources are
5 https://inrupt.com/, Inrupt
6 https://github.com/solid/solid-spec, Inrupt
7 https://www.w3.org/2005/Incubator/webid/spec/identity/, W3C
8 https://www.w3.org/2005/Incubator/webid/spec/tls/, W3C
6
grouped into subfolders of either the private or the public data folder. As indicated in section 3.2, access
rights can be regulated per graph or document, based on the .acl specification.
3.4 Solid SDK
As indicated in Section 1, the number of applications that use Linked Data remains limited. Since a
decentralised and distributed ecosystem such as Solid relies on third party developers for application
development, it needs to lower this development threshold. With this in mind, a dedicated Software
Developer Kit (SDK) for programming in React and Angular is provided. This includes a generator that
preconfigures the solid specifications (e.g. for security settings), so developers can focus on the
functionality they want to implement, instead of implementing the specifications themselves. It also
includes the Comunica framework (Taelman, Van Herwegen, Vander Sande, & Verborgh, 2018) for
querying Linked Data on the web, with SPARQL (SPARQL Protocol and RDF Query Language)9 or
its less verbose and more accessible variants GraphQL-LD (Taelman, Vander Sande, & Verborgh,
2018) and LDflex (Verborgh, 2018). The use of these more accessible query languages is also expected
to improve the development rate of Linked Data applications.
3.5 Solid for construction
The above mentioned specifications of Solid could easily be implemented for an AECO-oriented CDE,
possibly extended towards an ecosystem of Linked Data BIM bots. Future research should determine
the optimal configuration, although for this first paper we propose a preliminary approach, which will
also be used in the proof-of-concept application of Section 4.
In this workflow, the project manager creates a private project subfolder in his or her datapod. All
project stakeholders have their own datapod as well, and get the URI of the main project folder of the
manager. This does not mean that they have access to the contained files, as this can be managed
individually. This project folder should contain at least two graphs in the private data section. The first
one defines the minimal project information; the skeletonof the project in the form of its topology.
We suggest to use the modular Building Topology Ontology (BOT) (Rasmussen et al., 2017) as
recommended by the W3C Linked Building Data Community Group. BOT allows to identify different
zones within a building (site, building, storey, space) and define the relationships between them. The
second graph contains the WebIDs of different stakeholders and their function(s) in the project. This
stakeholders graph will be used to define access rights based on the role in the project. In case a
handover of the project data happens, or roles are switched within one project, access rights can
therefore immediately update.
Project stakeholders then create a project folder in their own pod as well, and upload the information
that is their responsibility, while linking it to the general project URI from the manager. They can
request access to project information from other stakeholders, to be able to link to this information as
well. Granting access to other project information might be done by the manager (who has access to the
entire project database by default) or by the responsible stakeholder. This way, an interlinked, virtual
environment starts to exist, which links the data and documents from the project stakeholders into a
web based graph; a Linked Data-based Common Data Environment. Ideally, only binary information
(imagery, point clouds) is stored as documents, while other information such as topology and product
data is stored in an RDF graph. However, the described workflow also supports a more traditional
document-based approach: a project management app that implements the ICDD ontologies could
easily generate an ICDD dump file of the project, mirroring the distributed online model.
Apart from this rough workflow, the Solid SDK and implementation of, for example, GraphQL-LD to
ease querying, could significantly stimulate development of Linked Building Data applications. A
general workflow for aligning such applications needs to be made in the future, so they can
9 https://www.w3.org/TR/rdf-sparql-query/, W3C
7
automatically communicate with one another and exchange information that is required for a certain
use case. This workflow could be based on the IDM and MVD specifications and include a method to
describe use cases in a modular way, where tools can be chained together, automatically validating their
inputs and outputs, for example with use of SHACL (Shapes Constraint Language)10. Such tools can
then use the RDF data in the distributed project pods for advanced reasoning, simulation, model
enrichment etc. At the moment, however, the first step is the setup of a prototype application for basic
management of building data.
4. Proof of concept: ConSolid
In this section, the workflow discussed in Section 3.5 will serve as a guideline for the development of
a rudimentary application for building data management, which is entitled ‘ConSolid’ (Construction
Solid)11. In the ideal case, the ConSolid app aids in the following building project management topics:
Configuration of the building project and its topology
Semantic enrichment of a building project with geometry, product data and properties
Configuration of the stakeholders and their role within the project
Uploading documents to building project folders
Linking document-based information to each other and to RDF graphs
Validating the distributed model with predefined validation shapes (e.g. SHACL)
Querying building project information
Generating ICDD project containers
The test application was generated with the Solid React generator12. As the development is work in
progress, not all functionality has been implemented at the time of writing: initial work has focused on
implementing project and topology creation, role assignment and uploading, linking and querying of
project information by the project manager. Semantic enrichment of the project with product data,
properties and geometric information has not been implemented yet. Strategies to integrate SHACL
validation in the ConSolid tool are discussed in (Werbrouck, Pauwels, Senthilvel, & Beetz, 2019).
4.1 Basic functionality
The generated application includes login functionality with one’s WebID. After logging in, the WebID
is stored, which allows the application to perform actions with the data stored in the user’s pod. In the
current implementation, we distinguish 3 main tabs, apart from the general ‘Home’ and ‘Profile’ tab:
‘Topology’, ‘Roles’ and ‘Connect’, respectively for managing the basic information of the building,
stakeholders and their roles and the connection of distributed project data.
Figure 3: Loading a building project from a user’s datapod in the ‘Topology’ tab
10 https://www.w3.org/TR/shacl/, W3C
11 The project code is available at https://github.ugent.be/jmauwerb/solid-cde
12 https://solid.inrupt.com/docs/writing-solid-apps-with-react
8
4.2 Project Topology
If the user is the owner of any project, it can be selected in the navigation bar and loaded from the
distributed pods of the stakeholders (Fig. 3). The basic building topology is then displayed in the
‘Topology’ tab, where it can be updated. Documents may be uploaded to the pod and linked to particular
zones in the building, as an alternative to the more advanced linking in the ‘Connect’ tab. If no projects
have been created yet, a new project can be created from scratch, stating the basic topology and setting
the creator of the pod as the project manager. As mentioned earlier, the ontology that is used for
topology description is BOT, although other ontologies such as ifcOWL could be used as well.
4.3 Role management
The ‘Roles’ tab allows the project manager to assign certain roles to certain WebIDs. These roles are
stored in a graph in the main project pod (using FOAF) and can be used for managing access rights. A
schema may be developed with some standard access rights that are mapped to certain roles, to
automatically set the rights that occur the most. Role groups can be configured from this data, which
means a more flexible approach than person-based access rights.
4.4 Data connection and container generation
In the ‘Connect’ tab, the user can upload files to their project pod. A stakeholder that is logged in may
upload files to her pod. Project files to which the user has access rights can be linked to one another, as
documents as well as on sub-document level. As indicated in Section 3.3, these project documents can
be Linked Data as well as non-Linked Data.
In order to allow optimal linking of documents and triples, different strategies may be used for different
file formats. Since the ICDD specification does not state how sub-document identifiers for certain
document formats are to be defined, there is no agreed upon system to refer to IFC GUIDS, pixel zones
etc. As this is a separate issue that is not considered part of this work, this prototype is currently limited
to linking and displaying RDF graphs and imagery. In future versions, 3D model viewers, text editors,
etc. could be implemented as well to support a broader variety of documents.
Figure 4: uploading and linking documents in the ‘Connect’ tab. Linked Data files may be queried
with non-specialist languages such as GraphQL-LD or LDflex.
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To simplify the querying of the Linked Data files, a test engine for GraphQL-LD has been implemented
(Fig. 4). This means that an end-user does not need to know the details of Linked Data to query the
available information. The query results can then be individually selected to link to other RDF
resources, documents or sub-document identifiers. As Solid pods also follow a container-like structure,
the implementation of functionality for generating an ICDD container should be quite straightforward.
4.5 Testing
Full testing of the tool’s functionality has not happened at the moment of writing, although the different
modules (project creation, topology, querying) have been tested separately and iteratively during the
development process. It lies within the ambitions to simulate a more complete project when the above
mentioned modules are more tightly integrated with one another.
5. Conclusion and Future Work
5.1 Conclusion
In this paper, we suggested the use of Linked Data for semantically connected Common Data
Environments. Because of the universality of RDF, such CDE could play a central role in a network of
modular applications that each envisage a certain activity in the Building Life Cycle. The scope of such
applications is therefore not limited to ‘typical’ construction activities, but could also include adjacent
domains such as historical or geographical data, Facility Management, circular economy etc. Modular
domain models, as proposed by the LBD Community Group, enable a more flexible approach to projects
that work with disparate data. It was shown that the idea behind the Solid ecosystem is similar to the
concept of BIM bots, but then in a Linked Data environment. A brief overview of the basic
specifications offered by this ecosystem for social linked data was given, and the potential for managing
Building Projects was illustrated. To finish, a prototype application ‘ConSolid’ was discussed, using
the SDK that preconfigures the specifications for the application. This service is still in a very early
development phase and thus highly experimental. Nevertheless, some basic functionality shows that a
decentralised management of building information is achievable with the available technology stack.
5.2 Future Work
As this work is only an introduction, future work might focus on multiple aspects. One aspect is further
develop the ConSolid application towards a more mature tool that can be used in practical situations.
Apart from the basic implementation discussed in Section 4, vocabularies for describing product
information and properties need to be implemented to be able to create realistic projects. This is a
prerequisite for testing the overall capabilities of the use case in a later development stage. Another
focus should lie on how multiple tools can access the building project data and communicate with one
another. For example, establishing a link with (existing) modelling packages will make the creation of
a basic Linked Building Data model more intuitive. Due to the decentralisation principle, other web
applications that are authorised to fetch the project data may further enrich or analyse the project, e.g.
by performing building performance simulations. When many tools are each dedicated to one small
task, they could be used as atomic building blocks in a tool chain that addresses larger use cases.
Semantic Web technologies such as SHACL allow validation of the information that is exchanged in
such chain. Having a way to configure and connect multiple, modular tools should also allow building
disciplines that lie beyond construction to collaborate and use the same data. However, such scenarios
require a more thorough interlinking of information on data level: rather than being stored in files, the
available information needs to be represented in RDF format as much as possible.
With this in mind, we hope this work can contribute to the advancements of the BIM community
towards an open BIM practice that is characterised by integrated web services and interoperable data.
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6. Acknowledgements
The authors would like to acknowledge the support by both the Special Research Fund (BOF) of Ghent
University and the BIM4REN project, which has received funding from the European Union’s
Horizon2020 Research and Innovation Program under grant agreement No 820773.
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... Linked Building Data (LBD) allows for vendor-neutral, decoupled, and softwareindependent information modeling using Semantic Web technologies. The modeled information is made available on the web, e.g., via Linked Data platforms or Distributed Common Data Environments (DCDE) [28], [26]. However, in the Architecture, Engineering, Construction, and Operation (AECO) industry, the information created in the life cycle of a building is always coupled with projectspecific tasks for creating, exchanging, or using certain information. ...
... Based on the usage of distributed heterogeneous data sources in a linked network, Werbrouck et al. [28] provided a concept for the utilization of LBD to develop a DCDE. Research and industry seized the term and concept of a DCDE to develop new interoperable solutions for the AECO industry, especially for collaboration. ...
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... Recently, the development of these systems has made possible the extraction and processing of information stored directly in the cloud environment, as well as the cross-linking and comparison of different models [103,104]. However, these approaches, which have prioritized finding solutions for data retrieval, have paid little attention to the modelling, structuring, and horizontal computation of information, whether it is present in the BIM model or added to an external database [105]. ...
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... Different data concepts can be linked as triples, a concept derived from basic sentence structures where a subject is linked to an object with a predicate, stating their relationship. This way, data can be semantically enriched, independent of the data type (Werbrouck et al., 2019). Despite its potential and research interest, the number of applications remains limited due to a steep learning curve and a high implementation threshold (Verborgh, 2018). ...
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Chapter
Das Kapitel fasst den aktuellen Stand der Umsetzung von Building Information Modeling zusammen und geht auf noch zu lösende Fragestellungen ein. Zudem gibt es einen Ausblick auf die zu erwartenden Entwicklungen in der nahen und fernen Zukunft. Dabei werden Konzepte wie Digitale Zwillinge, Künstliche Intelligenz und Robotergestütztes Bauen beleuchtet.
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BIMserver. org-An open source IFC model server
  • J Beetz
  • L Van Berlo
  • R De Laat
  • Van Den
  • P Helm
Beetz, J., van Berlo, L., de Laat, R., & van den Helm, P. (2010). BIMserver. org-An open source IFC model server. Proceedings of the 27th CIB W78 Conference on Information Technology in Construction, 8.
Using RDF Metadata to enable Access Control on the Social Semantic Web
  • J Hollenbach
  • J Presbrey
  • T Berners-Lee
Hollenbach, J., Presbrey, J., & Berners-Lee, T. (2009). Using RDF Metadata to enable Access Control on the Social Semantic Web. Proceedings of the Workshop on Collaborative Construction, Management and Linking of Structured Knowledge (CK2009), 514, 167.
Imagining Construction's Digital Future
McKinsey & Company. (2015). Imagining Construction's Digital Future. Retrieved from https://www.mckinsey.com/industries/capital-projects-and-infrastructure/ourinsights/imagining-constructions-digital-future