Full field imaging for damage evaluation in lightweight structures under impact type loading
Individual fellowship funded by European Commission
The research covers the development of understanding and accrual of knowledge on the behaviour of fibre reinforced polymer (FRP) composite materials, which are crucial to address current need to produce lighter, more fuel efficient and sustainable structures for transportation.
New full-field imaging approaches are increasingly used for the detection and analysis of damage in composites. The objective of the research program is to develop and verify a new methodology where integrated thermomechanical full-field high fidelity measures of stress and strain are provided experimentally. The research will for the first time provide quantitative inputs to models to inform designs and predict failure under high strain rate events through and experimentally derived damage index to determine structural performance.
The combined DIC-TSA approach offers significant advantages in studying the damage evolution in FRPs during high strain rate events. This hypothesis is based on the efficient and real-time nature of the full-field, non-contact measurement techniques and the fact that the two methods provide complementary information about the strain-state and stress-state of the composite and the potential to provide a damage index which can define structural performance.
This project will combine high-speed white light and IR imaging and obtain strains from DIC and stresses from TSA for the practically real-time assessment of damage in FRP composite structures subjected to high strain rate impact loading. This project will be conducted at the University of Bristol (UoB) and is complementary to the EPSRC funded CERTEST and Structures 2025. The vision of CERTEST is to revolutionise traditional approaches to structural testing, certification and validation by providing hi-fidelity measurements at a hitherto unachieved level of realism. FIDELITY supports this vision and adds significant benefit by investigating material and structural behaviour at elevated strain rates.
This project was funded by the European Union’s Horizon 2020 - MSCA - IF programme (FIDELITY project, grant agreement n◦ 846458).
Methods
The experimental methods used in the project include mechanical characterisation using Instron Electropuls, Split Hopkinson Pressure Bar and drop tower impact device. The thermal imaging is accomplished using Telops m3K high speed IR camera.
Key results
The results of the research will be compiled into three journal articles which will be submitted to high ranking journals, such as Composites Science and Technology, Composites Part B, and Composite Structures.
Partners
In addition to the academics in Bristol Composites Institute, the project will create collaborations with researchers in University of Oxford and University of Southampton.