Periodic Reporting for period 1 - NEWFRAC (New strategies for multifield fracture problems across scales in heterogeneous systems for Energy, Health and Transport)
Reporting period: 2020-05-01 to 2022-04-30
The optimal exploitation of the capacities of such systems requires a deep knowledge of different fracture mechanisms affecting their integrity. The total losses due to fracture in the modern society can achieve a few percent of the gross economic product. These losses are at least partially evitable by a proper investment in research and application of new computational strategies for fracture prediction. However, the current modeling tools are insufficient for failure prediction in heterogeneous systems with high level of complexity, where cracks are interacting with bimaterial interfaces (initiating at/approaching/crossing/deflecting at/propagating along interfaces and kinking towards adjacent bulk) and in which multiple physical phenomena are coupled and occur at different length scales simultaneously.
NEWFRAC is the first coordinated initiative in EU aiming at the systematic progress in the failure prediction in heterogeneous systems through a novel computational framework by integrating two modern modelling strategies: the Coupled Criterion of Finite Fracture Mechanics and the Phase Field Models of Fracture, developed significantly in the last two decades.
The overarching objective of the NEWFRAC network is a high-level training of a new generation of creative, entrepreneurial, and innovative early-stage researchers (ESRs) through the development and engineering applications of these modelling strategies focusing on the prediction and analysis of multi-field fracture phenomena in specific heterogeneous engineering systems at different scales.
The main research objective of the NEWFRAC network is the development of a new modeling and simulation framework for the fracture mechanics optimization of high-level technological products involving heterogeneous systems (materials and structures), employed in engineering fields of strategic societal and scientific impact, ranging from renewable energy production systems to biological hard tissues.
The most relevant scientific results obtained so far in the network are the following ones: - Application of Finite Fracture Mechanics at the micro-scale to bending tests of micro cantilever beams, - A humidity dose-cohesive zone model formulation to simulate new end-of-life recycling methods for photovoltaic laminates, - Analytical modeling of debonding mechanism for long and short bond lengths in direct shear tests accounting for residual strength, - Development of a new dynamic formulation of the coupled criterion of Finite Fracture Mechanics, - Development of a new phase field model for cracks under compression, - Development of a new phase field model for cracks in heterogeneous materials, - Study of a size-effect on the apparent tensile strength of brittle materials with spherical cavities.
1. Fragmentation and dynamic crack propagation.
2. Toughening composites by micro and meso structural optimization.
3. Simultaneous crack initiation and propagation interacting with interfaces.
4. Fracture prediction in human long bones.
5. Failure mechanisms of ultra-thin ply laminates.
6. Innovative solutions to the fracture of injection molded short fiber reinforced polymer composites.
7. Reinforcement of externally strengthened curved beams by fiber reinforced polymer composites in civil engineering.
NewFrac network guarantees the attendance of ESRs to all network wide training activities, and favours their training through interdisciplinary and intersectoral research, mobility, and exposure to industry, aiming at their transfer to industry after the NewFrac. It is expected that these ESRs will become experts in fracture prediction in heterogeneous systems and will contribute to reduce the innovation gap by enhancing two ways academia industry transfer of knowledge.