A new study shows groundbreaking advancements in damage detection technology for concrete infrastructure, utilizing a "virtual laboratory" to simulate and identify early-stage damage long before visible signs emerge. This innovative research highlights the potential of advanced computer modelling and Coda Wave Interferometry (CWI), a non-destructive testing technique, to detect micro-cracking in concrete and offer a new approach to infrastructure maintenance and asset management.
Scientists from Germany have been testing the highly sensitive Coda Wave Interferometry (CWI), originally developed for seismology, to track tiny changes in materials by analyzing the tail end of ultrasonic wave signals. The research team created a digital 'virtual lab' to simulate how ultrasonic waves propagate through concrete specimens under increasing compressive loads. The modelling included both aggregate and micro-crack levels, simulating mechanical degradation and generating synthetic ultrasonic signals to track changes over time.
The results of the research were promising: during early loading, the relative velocity of ultrasonic waves increased by up to 1.23 percent due to micro-crack closure. As loading continued, and micro-cracks began to form and coalesce, the wave velocity dropped significantly by around 3 percent. These changes were strongly correlated with reductions in the concrete’s stiffness, confirming the method's sensitivity to material degradation.
Importantly, the research also introduced statistical models that link ultrasonic signal changes to stress levels and failure probability, helping to improve structural health monitoring decisions.
"For infrastructure asset owners, the implications are significant. Traditional inspection methods often miss micro-cracking – especially when it occurs inside the material. The virtual lab approach allows us to simulate these early damage stages in a controlled environment, validate them against experimental data, and eventually apply the findings in the field," the research team noted.
While the study focused on compressive damage, the authors emphasized that tensile damage – a critical factor for structural performance – remains a key area for future exploration. The study also recommended future improvements, including modelling interfacial transition zones and testing under various environmental conditions like moisture and temperature.
This research points to a future where concrete infrastructure can be monitored more precisely, efficiently, and cost-effectively. The integration of CWI into structural health monitoring systems, especially when combined with machine learning or digital twin technologies, could help operators detect degradation at early stages, improving safety and extending asset life.
Reference: https://infrastructuremagazine.com.au/virtual-laboratory-concrete/
