Submitted by Simone Castello on Wed, 02/09/2020 - 09:48
Built Environment Digital Twinning has been published and is available for download. The report, authored by Ioannis Brilakis, Yuandong Pan, André Borrmann and associates from Siemens is the outcome of the International Workshop on Built Environment Digital Twinning, which was held in Germany in December 2019, co-sponsored by the Institute for Advanced Study of Technical University of Munich (TUM-IAS) and Siemens AG. CDBB was represented at the event by Mark Enzer, Head of the National Digital Twin Programme.
The workshop brought together Digital Twin (DT) experts from academia and the private sector, from diverse fields such as civil and environmental engineering, computer science and architecture. The experts explored research and technology transfer challenges, including how to automate Digital Twins (DTs) across scales and built environment asset types; how to structure them so they are standardised, scalable and verifiable; how to exploit their capabilities and keep them up to date with the latest innovation and how to introduce and promote them so they are accessible to businesses of all sizes and levels of digital maturity. A summary of key themes from the report is below.
Digital twins and the construction sector
The report starts with a definition by El Saddik 2018: “A digital twin is a digital replica of a real-world physical entity”. Other definitions include one by the Centre for Digital Built Britain, which describes a digital twin as “a realistic digital representation of assets, processes or systems in the built or natural environment” (Bolton et al. 2018).
Digital twins are digital replicas of physical twins, which can be residential buildings, commercial buildings, industrial factories, hospitals, railways, subways, bridges, roads, etc. A system of assets can be an entire city, knitting together residential and commercial buildings with social infrastructure, energy networks and water systems. The societal impact of digitalization of the built environment was subsequently covered in Flourishing Systems - Re-envisioning infrastructure as a platform for human flourishing, a paper jointly published by the Centre for Digital Built Britain (CDBB) and the Cambridge Centre for Smart Infrastructure and Construction (CSIC).
The construction sector has not fully embraced digitization and is lagging behind other industries. DTs can bridge the digital gap and offer substantial value to all stakeholders. The benefits of their adoption are underlined by this definition: “A digital twin is a dynamic virtual representation of a physical object or system across its lifecycle, using real-time data to enable understanding, learning and reasoning” (Gallan et al. 2019).
Digital twins need to be updated regularly to represent the current condition of the physical asset. They should be standardised yet flexible, allowing owners and operators to address use cases with extensions, while being cloud and computationally friendly, scalable and verifiable.
Digital twins and smart infrastructure
Government policies, in the UK and internationally, are increasingly focusing on the creation of smart, innovative cities, which make better use of data and technology to deliver economic growth and a higher quality of life. These policies are also influenced by issues like demographic rises, globalisation, pollution, energy sustainability and climate change.
At the workshop, researchers from Siemens AG addressed the pressing challenges of urbanisation, comprising building technology, decentralised energy systems and electrical infrastructure – issues that can benefit from digitization, smart networks, and energy-saving technologies. They presented a ‘trinity’ of digital twins: the digital product twin – i.e. containing data that can be used in design and simulation; the digital construction twin – i.e. 3D CAD data, floor plans, asset locations and the digital performance twin – i.e. data to evaluate the use and maintain an asset.
In the UK, the Centre for Digital Built Britain (CDBB) has been working on a “National Digital Twin” (NDT), envisaged as an ecosystem of connected digital twins. This approach fosters connections between transport, energy, telecoms, water, waste, social infrastructure and residential/commercial/industrial buildings within the natural environment.
Mark Enzer’s presentation underlined the requirement within the NDT concept of secure and resilient data-sharing among all stakeholders, including data exchange between the digital twin and the physical twin, as well as the data connection between different digital twins. This links to CDBB’s focus on developing an Information Management Framework (IMF) to facilitate secure data sharing, which can bring benefits to society, the economy, businesses, and the environment. Enzer shared the Gemini Principles, which will guide the development of the NDT and the IMF. An important point was that future DT standards should be decentralised, open, heterogeneous and interlinked.
Overall, digital twins can be deployed in different built environments and for diverse purposes, not just for building an asset but also for monitoring its condition; this is particularly crucial for assets subject to structural wear and tear, such as road and rail transport. The example of a sewer system illustrated how a twin could be used to identify flow disruption and potential blockages. Even air quality in a big city can be measured and monitored in this way.
In small-scale building, such as offices and residential buildings, a digital twin could foster sustainability by optimising environment conditions, which will increase user satisfaction and improve living conditions. Factors such as natural light, artificial lighting, heating can be simulated and monitored.
The application of blockchain was also discussed, to improve the security of digital data. This point was mentioned several times during the workshop, particularly the challenge of safely storing the data, transmitting it in a secure way and making it easy to access when required. Using blockchain can also reduce costs, aside making data secure.
Digital twins: benefits for owners and operators
Digital twins are transforming building processes from design and construction to operation and maintenance for the whole lifecycle of an asset. They can reduce costs for owners and operators, while ensuring information is accessible and safe.
The challenge is how to make them attractive to SMEs. Perhaps we can learn from construction tech adoption, originating from academic research through implementation by a start-up to start-up acquisition by an established vendor. Market penetration of digital twins can follow this route, highlighting the value and benefits to businesses of any size. Benefits include savings in operations, maintenance and learning in residential/commercial buildings and infrastructure.
Digital twins and BIM
Building Information Modelling (BIM) is an important component of the digitization of the construction sector. BIM covers the design, construction and operation of a built asset. Using BIM streamlines the process by storing all the information in a secure place, standardising the tools and formats, and fostering collaboration. There is a constant information flow, which reduces data loss between the planning and construction phase.
A digital twin, however, often includes broader concepts focusing on large-scale facilities and integrates information from other sectors. It can be used in the construction sector and in other projects, such as water, waste and power systems, helping the information exchange across all networks.
BIM models provide a reliable basis for setting up a digital twin because they can integrate information ranging from geometric changes in the building layout over monitoring the condition of structural components (degradation) to the occupancy and use of rooms and spaces. Digital twins for buildings can be seen as BIM models extended to capture real-world data and feed it back into the model, thus neatly closing the information loop.