From design to management and checking
The advancing digitalisation leads to ever more areas of application for the metrological, sensor-based monitoring of structures. By recording real actions and structural reactions, structural health monitoring (SHM) creates new possibilities for the assessment and maintenance of ageing infrastructure structures. Measurement technology can also support and complement structural inspections, thus facilitating predictive maintenance strategies.e Einsatzbereiche. So schafft das Bauwerksmonitoring durch die Erfassung realer Bauwerksreaktionen und Einwirkungen neue Möglichkeiten zur Bewertung und zum Erhalt gealterter Infrastrukturbauwerke. Auch die Bauwerksprüfung kann durch Messtechnik sinnvoll unterstützt und ergänzt werden, wodurch eine prädiktive Instandhaltungsstrategie greifbar wird.
GRASSL engineers possess extensive experience in structural health monitoring. In multiple projects, they have been able to integrate the specific challenges and possibilities of SHM in the consideration of various topics. These projects demonstrate, for example, how the remaining service life of steel bridges can be extended, how the tender for SHM for an inner-urban tunnel structure is carried out successfully or how the SHM of a complex new build is considered in the very first stages of design. Furthermore, SHM methods are used to support structural inspections via specific interfaces.
SHM as an aid to structural inspection
Structural inspection can be thought of as the original form of SHM, although with very low temporal resolution. Initially limited to analogous methods, the subjective impression of a structural inspector, augmented by the advancing digitalisation and supported by the use of measurement technology or imaging methods, can achieve reproducible results about the condition of a structure. Thus it becomes possible to apply a predictive maintenance strategy. We use leading-edge methods such as drone flights and 3D scans to support our structural inspections. Thanks to continuous SHM data acquisition and the resulting data history, the cause of damage and its effects on the structure in the context of a specific damage analysis can be determined more accurately and efficiently and assessed more reliably. SHM thus complements and extends the field of structural inspection by opening up new possibilities and offers the option to generate more detailed information about the current condition of a structure.
SHM as part of structural maintenance
Besides our extensive experience in the analytical structural assessment of structures, in the area of structure maintenance we go one step further. By carrying out measurements to observe damage, trying to understand the cause of damage during structural inspections and feeding the results back into the analytical assessment of the structural behaviour and damage state, results can be verified and the remaining service life determined and monitored. Our monitoring systems provide detailed information about the actual loads and actions, the structural behaviour and possible structural reserves within the safety concept of the structural verification. Continuous measurements can further be one type of compensation measure if the structure is determined to have insufficient structural capacity. They can also be used in a maintenance strategy if a damaged structure cannot be replaced or rehabilitated within a short time frame.
We offer the entire spectrum of services, from feasibility study, SHM concept, tendering and execution design to data processing and the presentation and interpretation of results.
SHM during construction
During construction, the continuous, metrological surveillance of the actual actions of structures under construction or under service loads can be beneficial. If necessary, we even develop SHM concepts in the preliminary design phase that can be integrated in the execution design or tender documents, for example. We consider SHM methods for large (semi-) integral structures and complex and unique construction methods, for example, where measurement data from the start of the structure’s service life can be used as a reference for the healthy structural state and to verify analytical assumptions. Deviations can be recognised and compensated for early on. Permanent damage occurring later on serves as damage indicators. With these SHM methods, we contribute to the predictive maintenance of new structures. The concepts for and management of measurements taken during construction (shoring of foundations and underpinning of existing structures, for example) complete our portfolio.
