The Digital Construction Site Construction Industry 4.0: TU Braunschweig researches digital technologies with new large-scale equipment

Houses, roads, bridges – construction is always in progress. But mostly using traditional construction techniques that have remained unchanged for decades. While digitalisation and automation are being integrated into industrial production in other industries, the construction sector suffers from costly, unproductive and environmentally damaging site processes. Digital solutions are rarely used in construction and have been limited to selected applications and pilot projects. However, the construction industry is facing the challenge of meeting the growing demand for construction with fewer resources and emissions in the future. With the project “Die Digitale Baustelle – Bauindustrie 4.0 als Schlüssel für eine digitale und nachhaltige Bauwirtschaft“ (The Digital Construction Site – Construction Industry 4.0 as the Key to a Digital and Sustainable Construction Industry), Technische Universität Braunschweig aims to research digital production technologies and their impact on planning and production processes under real construction site conditions and to provide impetus for construction practice.

To this end, a unique research infrastructure is being built in Beethovenstraße on the East Campus of TU Braunschweig, consisting of a variety of digitally controlled large-scale equipment – including robotic units, mobile robots, an automated concrete mixing plant, object tracking and immersive systems (including an LED wall with virtual reality technology). The centrepiece of the facility is the approximately six-metre-high 3D printing unit, which will be used to produce large, individualised, resource- and CO₂-efficient components additively, i.e. in several superimposed layers.

“Additive manufacturing technologies and 3D concrete printing in particular are key technologies for the transformation of the construction industry, as they combine economic, ecological and social aspects of construction production,” says Professor Patrick Schwerdtner from the Institute for Construction Engineering and Management (IBB), one of the initiators of the digital construction site and project manager for the planning and procurement phase. Not only does the elimination of formwork eliminate a costly step in the process, but the additive manufacturing process also saves material because the concrete is only used where it is actually needed. Work safety is also improved as the components are produced automatically rather than by hand in sometimes difficult local and weather conditions.

Innovative integration of digital technologies

TU Braunschweig is already researching 3D concrete printing and other additive manufacturing technologies together with TU Munich in the Collaborative Research Centre TRR 277 “Additive Manufacturing in Construction” (AMC). Professor Harald Kloft, spokesperson for the Collaborative Research Centre, sees enormous potential in the digital construction site for applying the results of basic research. Here, the scientists want to test the results of the AMC on a 1:1 building scale and under real conditions. They want to bring together various digital technologies on site and network them in the spirit of Industry 4.0. Norman Hack, Professor of Digital Construction at the Institute of Structural Design (ITE), explains that in the future it will be possible to work with data on the construction site – from planning to production and assembly. Ideally, this will create a digital process chain that increases the level of automation. The advantage: construction can be more resource-efficient, long transport routes are eliminated and construction time is reduced thanks to interlinked processes. In addition, the data-based exchange of information avoids communication errors.

Visual collaboration model

The interface for all parties involved in the production process is the “Digital Engineering Centre”: this control centre will bundle all information from the “digital construction site” – stored and managed in a three-dimensional “BIM model” (also for “conventional” construction processes outside of additive manufacturing). The researchers also want to use the Building Information Modelling (BIM) as a visual collaboration tool. “Here we can link three-dimensional representations with schedules, for example, to look at processes in a time frame and to collect and analyse data,” explains Professor Schwerdtner. The Digital Engineering Centre will also act as a virtual reality laboratory, where digital components can be projected into real space.

New ways of quality control

The digitally controlled concrete mixing plant for 3D printing (Mobile Digital Concrete Plant) also combines previously separate processes into a digitally integrated process. In this way, the production of the material can be controlled by mixing the raw materials, pumping the concrete and determining the properties of the fresh concrete and its flowability to ensure the printed geometry of the structure and the bonding of the individual layers”, explains Dirk Lowke, Professor of Building Materials.

The researchers, led by Professor Markus Gerke from the Institute of Geodesy and Photogrammetry (IGP), also want to use automatic 3D surveying sensors and methods for accompanying and final quality assurance. Among other things, this will enable them to check the actual and target geometry and to detect damage. It is also planned to use special tracking systems to record the entire structure for comparison with the design data. At the same time, the scientists will measure weather and wind conditions to analyse the effects of real construction site conditions.

Construction industry involvement

In the future, a construction site similar to the one at TU Braunschweig could become reality. “With our project, we want to demonstrate the possibilities of a future construction site infrastructure,” says Professor Schwerdtner. “Given the diversity of construction projects and construction methods, there will certainly be a multitude of possible concepts. With our research, we want to provide important impulses that can be built upon.“

Regional and national industry will be involved in the project and in subsequent research projects. Professor Schwerdtner also sees this as a clear offer: “In the ‘Digital Construction Site’ we are combining basic and application-oriented research. Planning offices and construction companies should familiarise themselves with possible future technologies at an early stage and integrate these considerations into their corporate strategy, as the transformation process will take some time”.

Project data

The project “The Digital Construction Site – Construction Industry 4.0 as the Key to a Digital and Sustainable Construction Industry” was initiated by five professors at TU Braunschweig. In addition to the Institute for Construction Engineering and Management (Professor Patrick Schwerdtner), the Institute of Structural Design (Professor Harald Kloft, Professor Norman Hack), the Institute of Building Materials, Concrete Construction and Fire Safety (Professor Dirk Lowke) and the Institute of Geodesy and Photogrammetry (Professor Markus Gerke) are also involved in the project. The research infrastructure is being funded with around 3.8 million euros from the European Regional Development Fund (ERDF), including an own contribution of ten per cent. The Lower Saxony Ministry of Science and Culture (MWK) is implementing the funding as part of the guideline “Innovation durch Hochschulen und Forschungseinrichtungen“ (Innovation through Universities and Research Institutions).