Building Materials and Process Engineering
Materials, Processes and Machines
The Building Materials and Process Engineering research field investigates and develops the scientific and technical bases for the extraction of raw materials and the production and pro-cessing of building materials. Its tasks and responsibilities essentially result from the close interaction between materials, processes and equipment. The only way to implement effecti-ve new solutions or improve existing processes is thus to adopt a holistic view and to engage in close collaboration between the fields of materials science, process engineering and me-chanical engineering.
Concrete and other mixes
In a multitude of projects, an exceedingly wide range of concrete and other mixes are being developed and improved with respect to their material characteristics and workability parame-ters. Materials include conventional ready-mixed and cast-in-place concrete, self-compacting and ultra-high-performance concrete (SCC and UHPC), fibre-reinforced concrete as well as textile, light-weight, aerated and foam concretes, mineral foams, compounds for dry mortar products, soil mortar and plastic-bound polymer concrete.
Polymer concrete
Conventional cement concrete is often not resistant in chemically aggressive environments. The result is high economic damage due to component failure. Polymer concretes are pro-duced using binders based on polymers. The concrete obtained is impermeable to liquids, highly resistant to chemicals and capable of withstanding high mechanical loads. Together with partners from industry, IAB develops novel polymer concrete formulations and products for demanding applications.
Ceramic raw materials and ce-ramic materials
As the oldest man-made building material, brick must respond to steadily increasing require-ments regarding its physical properties. We are working on innovations related to raw materi-als and the production process so as to keep brick competitive both in terms of its physical properties and its commercial viability. This research is also inextricably linked to reducing energy consumption and lowering CO2 emissions in production and processing. We conceive sustainability strategies, investigate potentials and develop approaches to the efficient use of resources and waste materials.
Clay building materials
Clay meets all the requirements for a modern, ecological or building biological binding agent. In the production of earthen building materials, almost little energy is used and almost no CO2 is emitted. Clay building products are not only used in residential construction, but also more and more frequently in the expansion and conversion of large commercial premises and public building complexes. Public authorities are increasingly opting for this building material for the renovation of schools and kindergartens in order to benefit from its outstanding clima-tic properties. Research work at the IAB is concerned with product developments around the building material clay. In addition to clay building boards and finish products for wall surfaces, the prefabrication of clay walls is the focus of research.
Regenerative raw materials
Furthermore, increasing efforts are being made to conserve primary resources and to promo-te building with regenerative raw materials. Related research activities pertain not only to wood, but also to the use of hemp, miscanthus and various types of grain.
It´s the Process that Matters Most
Material analysis
Most road pavements are still built with asphalt, even though the significance of concrete in road construction has continuously increased in the past few decades. Requirements for road infrastructure become more and more demanding due to constantly increasing payloads in truck traffic. This situation opens up a huge potential for an additional field of research. Con-ventional asphal grades are continuously being improved and optimised to reflect the ever-changing specifications and conditions for their use. For all material systems mentioned above, the IAB applies state-of-the-art methods of material analysis and standardised construction material tests. Machine measurements are conducted simultaneously to analyse and evaluate sequences of existing process steps.
Basic operations: mechanical and thermal process engi-neering
- Extraction and storage
- Conveying and batching
- Crushing and grinding
- Mixing and classifying
- Firing and calcining
- Agglomerating and moulding
- Reprocessing and recycling
The above list is non-exhaustive because the IAB’s resources enable research into almost all material-related processes. Furthermore, these processes determine the related equipment, which comprises a large number of devices, systems and control components. Our work primarily deals with processing machinery for granular and pasty materials. Crushing, mixing and compaction units must increasingly cope with highly complex material systems. The ran-ge of materials under study includes fluids, suspensions, foams and granular materials as well as complex, multi-phase systems that combine the characteristics of several individual pha-ses.
Control Accuracy Exactly to Specifications
Quality control systems
One of the main areas of activity of the IAB is the development of sophisticated quality con-trol systems. This work concentrates on measurement and analytical systems used for quan-tifying material behaviour. Data gathered by these systems is subsequently passed on to in-strumentation and control components and thus contributes to improving quality in production.
Optical measuring methods
Optical measuring methods used in process monitoring are of particular interest to IAB rese-archers. This is where image processing systems come into play because they are easy to use in quality control. They visualise important characteristics of the material, such as its tex-ture and colour stability. This approach is complemented by methods based on fibre optics that enable high-resolution temperature and strain measurements along the entire length of a light conductor.
Engineering
Devices or systems required for this purpose are developed from the ground up if existing equipment does not meet the agreed specifications. Prior to this development activity, the method best suited to the relevant basic operation is selected and dimensioned in process engineering terms. In the next step, the required machines are developed, designed and engi-neered, and various prototypes are tested.
Optimization
A range of numerical methods is applied in parallel with conventional development and design work in order to optimise existing systems and equipment under development. Numerical models of the overall system are derived from the analysed material characteristics and ma-chine geometry. These models reflect both the material system to be processed and the dy-namics of the machine.
Numerical simulations
Following reliable model validation, numerical simulations are applied to calculate various scenarios that create the basis on which to improve relevant components even further whilst also significantly enhancing process understanding.