Publications

Acoustic emission (AE) is casually used for characterization of materials and structures. The damage mechanisms emit elastic signals with distinguishable characteristics allowing their identification as has been verified in all types of cementitious media, masonry, and polymer composites. Furthermore, the sensitivity of AE allows conclusions earlier than the moment of damage manifestation, providing therefore, early data in a structural health ...

Researchers are looking for new eco-friendly products to preserve non-renewable and non-biodegradable resources. Fibres obtained from natural sources offer indisputable advantages over synthetic reinforcement materials,
including low density, low cost, abundance, comparable strength, non-toxicity and minimum environmental impact. However, when using natural fibres in a pure Portland cement matrix, the mechanical strength is significantly ...

Carbon Fiber Reinforced Polymer (CFRP) composites are broadly used in engineering applications. Their inherent anisotropy due to different fiber orientations can be considered an advantage since the strength of the component can be designated in preferential loading directions. However, this anisotropy leads to multiaxial stress conditions, complicating their damage sequence and mechanical response. Identification of these multiaxial conditions ...

Acoustic emission (AE) is used for characterization of materials condition. Detection of cracks, localization, fracture mode determination is conducted in laboratory conditions, while certain features are applicable in-situ. It is established that the dominant damage mechanism emits signals with distinguishable characteristics allowing its identification. This has been verified in all types of cementitious media (mortar, concrete, steel fiber- ...

The inherent anisotropy of composites complicates their damage response. The influence of multiaxiality is not thoroughly understood due to obstacles related to damage monitoring during loading. In this study, the response of carbon/epoxy laminates under fatigue is examined through in-situ microscopic observations. [0o/θ]2s, [0o/θ/0ο/-θ]s and [0o/θ/-θ]2s laminates with two off-axis angles, namely 30 and 60 degrees, are tested under fatigue. By ...

In fracture tests, the sharpness of the pre-crack is highly important and can affect the test results considerably. Although lots of studies have been done regarding the investigation of the effects of different crack sharpening methods on the results of mode I fracture tests, to the best of the authors’ knowledge, not many experimental studies are available for the case of polymer materials under mode II loading. Accordingly, in this study, an ...

Designing a production process such as thermoforming for thermoplastic composites might be challenging as it requires material characteristics at high temperatures. Material characterization tests (e.g., bias extension) in the molten state can encounter several difficulties, one of the most important ones is maintaining a uniform temperature distribution on the sample. Accordingly, during this research, a set of thermal tests has been initially ...

As one of the primary load-carrying materials, adhesives play a crucial role in the structural integrity of composite-made wind turbine blades. A thorough understanding of the mechanical behavior of adhesives in terms of fracture behavior is mandatory in order to optimize the blade design. Fracture analysis of trailing edge failure revealed that mode III contributed the most to the strain energy release rate, with flapwise shear and torsion ...

The production of plastic has grown exponentially over the past few decades and with it the amount of plastic waste leaking in the environment, where it fragments into micro- and nanoplastics. This problematic situation stresses the need for increased plastic collection, recycling and reuse rates. Extrusion-based additive manufacturing (AM) and especially fused filament fabrication (FFF) offer an efficient and effective method to reuse and ...