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A framework for characterising the reflection intensity of a 3D-CP mortar
No full textThe growing interest of 3D Concrete Printing (3DCP) arises new challenges for quality control. A major challenge lies in evaluation of the interlayer bond strength. An optical approach is developed to monitor the surface properties of the printed layer. Commercial laser profile scanners are utilised to record the reflection intensity of the mortar’s surface. To be applicable in the printing process, the reflection intensity needs to be characterised for each material within the printable region and further effects, like geometry and environmental light, need to be considered. The presented work aims to provide a framework for implementing the laser reflection intensity to 3DCP monitoring
On potentials and challenges of physics-informed SHM for civil engineering structures
No full textPhysics-informed structural health monitoring, which integrates realistic physical models of material behavior, structural response, damage mechanisms, and aging processes, offers a promising approach to improve monitoring capabilities and inform operation and maintenance planning. However, the associated technical challenges and model requirements are context-specific and vary widely across applications. To illustrate the relevance and potential of the topic, two application examples are presented. The first focuses on monitoring the modal characteristics of a prestressed road bridge, where strong sensitivity to temperature variations limits the diagnostic capabilities of conventional vibration-based global monitoring. The discussion highlights how environmental influences can obscure structural changes, and emphasizes that purely data-based approaches are inherently limited to detecting anomalies and do not enable comprehensive condition diagnostics. The second example explores a physics-informed monitoring approach for prestressed concrete bridges affected by hydrogen-induced stress corrosion cracking
Ringversuche – Werkzeug für Referenzmaterialzertifizierung und Eignungsprüfung
No full textEs wird ein Überblick gegeben über Ringversuchsaktivitäten der BAM zur Eignungsprüfung und Referenzmaterial-Charakterisierung. Anhand verschiedener Beispiele werden mögliche Probleme und deren Überwindung aufgezeigt
A Modular Gaussian Process Regression Toolbox for Uncertainty Aware Geotechnical Site Characterization
No full textA modular Gaussian Process Regression toolbox for efficient large-scale geotechnical site characterization from sparse 1D data was presented at the Third Future of Machine Learning in Geotechnics (3FOMLIG), Florence, Italy, October 16, 2025. The PyTorch/GPyTorch-based framework enables multivariate modeling of correlated soil properties and joint regression-classification of continuous CPT parameters with categorical soil units through Dirichlet transformations. Stochastic Variational Inference reduces computational complexity from O(N³) to O(M³), enabling GPU-accelerated processing of 100,000+ measurements. Validated on a 33 km² North Sea offshore wind farm site with 100+ sparse investigation points, the toolbox generates uncertainty-aware 3D predictions, supporting univariate, multivariate (LMC), and sequential multi-group modeling strategies
The critical role of safety in hydrogen and energy projects across the continent
No full textSafety plays a critical role in the success and sustainability of hydrogen and energy projects across Africa, where the push for clean and renewable energy is rapidly gaining momentum. Given hydrogen’s flammability and the complex infrastructure required for its production, storage, and transport, strict safety protocols are essential to protect workers, communities, and the environment. In regions with developing regulatory frameworks, establishing robust safety standards and fostering a culture of safety is vital to attract investment, ensure public trust, and prevent accidents that could derail progress. Prioritizing safety not only safeguards lives but also supports the long-term viability and credibility of Africa’s emerging hydrogen economy
Influence of Internal Pressure Regulation During Filament Winding on Failure Mechnism in Type 4 Pressure Vessels: A Case Study
No full textHydrogen storage is a crucial part of the hydrogen value chain, particularly in terms of safety and social acceptance of hydrogen technologies. For on-board and transportation applications, hydrogen is commonly stored as a compressed gas in pressure vessels. Full composite wrapped Type 4 pressure vessels are especially beneficial due to their high weight-saving potential and their capability to withstand high working pressures. To maintain an appropriate safety level, the mechanical behavior of the composite structure has been the subject of investigation in numerous studies. In this study, the failure mechanisms of two designs of Type 4 cylinders are investigated. The two designs differ solely in the manufacturing process parameters, particularly the internal pressure applied during the filament winding process. Variations in internal pressure result in different residual stress states and changes in the quality of the composite structure. The stacking sequence, materials used, and other manufacturing parameters remain unchanged. The cylinders show different failure mechanisms in slow burst tests: one design fails in hoop windings, while the other one fails in helical windings, despite no stress exaggeration in the fiber direction being observed with embedded optical fibers or in numerical simulations. To explain the failure mechanisms, the quality of the cylinders is investigated. The results of X-ray computed tomography and pulse-echo investigation, highlight the complexity of the interactions between manufacturing process parameters, residual stresses, manufacturing quality, and the mechanical behavior of composite pressure vessels. Resin-rich areas in the composite material are identified as a possible cause of the differing failure mechanisms
Experimental Determination of CCT Diagrams and Simulated HAZ Microstructures in Low-Alloy Pipeline Steel for H2 Transportation
No full textThis study investigates the suitability of low-alloy pipeline steels for hydrogen transportation, focusing on the development of weld microstructures. Previous research has been limited by a deficiency in the understanding of how different microstructural components respond to trapped hydrogen. By developing Continuous Cooling Transformation (CCT) diagrams through dilatometry analysis, this study explores the impact of t8/5-cooling times (the time between 800 °C and 500 °C) on the microstructure and mechanical properties of the HAZ compared to the base material. The findings provide valuable insights into how cooling times influence transformation temperatures and microstructure development, which, in turn, affect hydrogen diffusion and absorption. These findings establish a foundation for future investigations into hydrogen's impact on weld microstructures, including experimental studies, with the aim of optimizing welding practices and enhancing resistance to hydrogen-assisted cracking. Ultimately, this research contributes to improving the safety and reliability of hydrogen transportation systems in commonly used industrial pipeline steels
Thermographic Reference Dataset: Experimentally simulated Gaussian-shaped internal defects in GFRP
No full textWe introduce a thermographic reference dataset consisting of 100 experimentally recorded temperature fields that replicate defect-like heat signatures in glass fiber reinforced polymer (GFRP) composites. Instead of relying on the fabrication of numerous damaged specimens, the dataset was generated by directly imprinting defect signatures onto an intact laminate using a near-infrared laser projector with spatial light modulation. The projected patterns are derived from parameterized Gaussian distributions, enabling systematic variation in defect size, shape, and orientation. The resulting steady-state thermal responses were captured with infrared thermography, providing high-resolution temperature distribution measurements for each case. This novel approach ensures that the heat transfer physics are preserved experimentally, while no special samples with different defects need to be manufactured to acquire datasets for different defect parameters. The dataset is ultimately designed as a resource for the benchmarking of thermographic non-destructive testing techniques, the validation of numerical heat transfer simulations, and the training of data-driven algorithms for defect detection in composite materials
Digital LabHub - Gemeinsam die digitale Transformation der Laborbranche vorantreiben
No full textAls zentrale Drehscheibe für Information und Vernetzung begleitet der Digital LabHub Labore auf dem Weg der digitalen Transformation: praxisnah, kollaborativ und zukunftsorientiert. Die Drehscheibe bietet Orientierung, fördert den Austausch und macht bestehende Initiativen sichtbar. Der Digital LabHub bringt Akteure aus der und um die Laborbranche zusammen, um Wissen zu teilen, Synergien zu schaffen und Innovationen voranzutreiben
Wasserstoffinduzierte Spannungsrisskorrosion Beispiel: Spannblockverfahren
No full textBei der wissenschaftsjournalistischen Veranstaltung WISSENSWERTE 2025 in Berlin stellte die BAM die Aktivitäten zu den Themen Brückensicherheit und Bauwerks-Monitoring vor. Der Beitrag zur wasserstoffinduzierten Spannungsrisskorrosion wurde am Beispiel des Spannblockverfahrens erläutert, einem Spannverfahren für Brücken. Die Schadinitiierung im gezeigten Beispiel ereignete sich in der Bauphase zwischen dem Vorspannen der Drähte und dem Verpressen mit Mörtel. In dieser Phase wirken drei wesentliche Einflüsse zusammen und lösen Spannungsrisskorrosion aus, welche irreversible Schädigungen in Spannbetonbrücken induzieren können