Staff profile

After graduating in Structural Engineering from the Warsaw University of Technology, Stefan studied for an MSc in Simulation Techniques in Mechanical Engineering at RWTH-Aachen (Germany). Subsequently, he worked as a research engineer on rock-shed protective structures over highways in Kanazawa, Japan (2003-05). Szyniszewski then studied for PhD at the University of Florida (2009), where he developed an energy flow approach to the progressive collapse of framed structures. Stefan also described the propagation of column buckling waves in framed structures during the progressive collapse. He then spent two years in industry, working for Bechtel Power Corporation and Areva on the design of a new generation of nuclear power plants in the United States. Szyniszewski achieved a Professional Engineer (PE) status in California (2011), which is equivalent to Chartered Engineer (CEng) in the UK. Stefan returned to academia as a post-doctoral research fellow at the Johns Hopkins University, where he studied cellular metals and 3D woven lattice materials (DARPA funded project). Stefan developed homogenized models of cellular structures and derived analytical formulas for the ultimate buckling capacity of sandwich panels with metallic foam core. Szyniszewski also developed models of framed structures under dynamic and extreme loads for the Applied Physics Lab (APL). Subsequently, Stefan returned to Europe and joined the University of Surrey as a lecturer in Material and Structures in 2012. Stefan was appointed as an Assistant Professor at Durham University in 2019.

Research and Teaching

Stefan's primary interest is in hierarchical structures such as 3D woven technical composites, cellular metals with ceramic segments or multi-scale (fractal-like) lattices. He also develops materials models, novel simulation techniques and characterises these multi-scale structures experimentally. His work concentrates on dynamic features such as vibrational damping, wave propagation and shock dissipation, where evolution in time is critical. Stefan aims at increasing resource efficiency by light-weighting structures and incorporating multiple functionalities by designing hierarchical, multi-material structures at the material and component level.

Stefan's work is inspired by biological structures, which self-assemble across 8-11 length scales, where smaller elements are building blocks for the larger components, and so on. 3D woven composites are made of tens to hundreds of yarns, and each thread is made of 8-12,000 carbon fibres. Use of fibres is advantageous because material crystals are aligned in the loading direction, and it offers the best strength to weight ratio. Cellular metals with ceramic segments enable the interaction between the micro-porous cell wall (sized in microns), ceramic segments in mm, and the entire component (meters length scale). Even familiar steel-framed structures exhibit hierarchy ranging from metal grains to hot-rolled or cold-formed plates (making up structural components such as beams and columns) to the entire system such as a moment-resisting frame (4 levels of hierarchy).

Stefan's main research focus is on understanding and design of human-made, hierarchical structures to achieve novel, unique properties and to maximise their functional features. One example is the minimisation of vibrational damping and maximisation of stiffness through the use of 3D woven, hierarchical composite. Another example is a non-cuttable material made of cellular metal, ceramic segments and short metallic fibres. These architectures have been conceived through the use of LS-DYNA and ANSYS software packages, principles of physics in conjunction with experimental validation and subsequent improvements of simulation techniques.

The second thrust of Stefan's research is focused on the solutions required for the understanding and modelling of hierarchical structures such as:

• Development of homogenised models of porous materials,
• Identification of heterogonous material properties from digital image correlation (DIC) data obtained from physical tests,
• Stochastic material models relying on the generation of random fields of material properties,
• Analysis of energy flow during the progressive collapse of framed structures,
• The analytical equations for the compressive/buckling capacity of sandwich panel plates.

Stefan's current research aims at the creation of protean materials, which evolve and respond to a specific loading through the design of their internal material architecture to generate bespoke behaviours under these prescribed loads. The goal is to achieve functional materials through the use of hierarchical structures leveraging multi-physical phenomena such as vibrations, frictional heating, strain rate effects, phase changes of their base constituents, wave reflections, refractions, scattering and many other physical phenomena observed in nature.

In the School Stefan currently teaches structural design at L3 and MSC level. He is also developing a module on structural dynamics at L4. Stefan is a fellow of the Higher Education Academy in the United Kingdom and is licensed as a Professional Engineer (Chartered Engineering) in California, USA (License #79332).

Research Positions

Currently, the following funded positions are available:

• PhD studentship | Maximizing damping of wind energy structures through the use of locally resonating yarns embedded in 3D woven composites. See detailed description here,
• PhD studentship | Durham University also offers competitive studentships for UK, EU and overseas students. Funding for these PhDs is competitive but do not let that stop you from considering it. Apply online here,
• If you are interested in any of the topics you see above, please send me an email so we can discuss those in detail …

• Computational mechanics
• Architected materials and structures
• Material characterization (including digital image correlation and computer tomography)
• Structural dynamics
• Wave propagation
• Finite elements
• Stochastic material models

• 2019: Editor of Cellular Metals, which is part of SpringerMaterials:
• 2019: Member of Technical Committee on Architected Materials at Engineering Mechanics Institute (EMI) of American Society of Civil Engineers (ASCE):
• 2019: Organizer of a mini-symposium on Architected Materials as part of ASCE Engineering Mechanics Institute (EMI) International Conference in Durham (here!) from 5 to 8 April 2020:
• 2018: Third Prize Winner from Institute of Materials, Mineral and Mining (IOM3) during Materials Research Exchange forum for the work on metallic foam ceramic composite with extreme cutting resistance:
• 2017: University of Surrey Vice-Chancellor Award in Red Tape Challenge:
• 2008: Best Paper Award for 'Progressive Collapse Simulation of Steel Frame Structures - Accomplishments and Validation Challenges.' IABSE Conference. Helsinki, Finland:

Journal Article

• Guerra, N. B., Pires, A. V., Matthews, S., Szyniszewski, S., & Vieira Jr., L. (2023). An optimization method for stochastic reconstruction from empirical data - A limestone rock strain fields study-case using digital image correlation data. MethodsX, 10, Article 102141. https://doi.org/10.1016/j.mex.2023.102141
• Carstensen, J. V., Lotfi, R., Chen, W., Szyniszewski, S., Gaitanaros, S., Schroers, J., & Guest, J. K. (2022). Topology-optimized bulk metallic glass cellular materials for energy absorption. Scripta Materialia, 208, 114361. https://doi.org/10.1016/j.scriptamat.2021.114361
• Tavares, M., Weigand, J., Vieira, L. C., Almeida, S., & Szyniszewski, S. (2020). Mechanical Behavior of Steel and Aluminum Foams at Elevated Temperatures. Local buckling based approach toward understanding of the material system behavior. International Journal of Mechanical Sciences, 181, Article 105754. https://doi.org/10.1016/j.ijmecsci.2020.105754
• Szyniszewski, S., Vogel, R., Bittner, F., Jakubczyk, E., Anderson, M., Pelacci, M., …Hipke, T. (2020). Non-cuttable material created through local resonance and strain rate effects. Scientific Reports, 10, Article 11539. https://doi.org/10.1038/s41598-020-65976-0
• Salari-Sharif, L., Ryan, S. M., Pelacci, M., Guest, J. K., Valdevit, L., & Szyniszewski, S. (2018). Damping of selectively bonded 3D woven lattice materials. Scientific Reports, 8(1), Article 14572. https://doi.org/10.1038/s41598-018-32625-6
• Liu, Z., Jacques, C., Szyniszewski, S., Guest, J., Schafer, B., Igusa, T., & Mitrani-Reiser, J. (2016). Agent-Based Simulation of Building Evacuation after an Earthquake: Coupling Human Behavior with Structural Response. Natural Hazards Review, 17(1), https://doi.org/10.1061/%28asce%29nh.1527-6996.0000199
• Ryan, S. M., Szyniszewski, S., Ha, S., Xiao, R., Nguyen, T. D., Sharp, K. W., …Hemker, K. J. (2015). Damping behavior of 3D woven metallic lattice materials. Scripta Materialia, 106, https://doi.org/10.1016/j.scriptamat.2015.03.010
• Szyniszewski, S., Smith, B., Hajjar, J., Schafer, B., & Arwade, S. (2014). The mechanical properties and modeling of a sintered hollow sphere steel foam. Materials & Design, 54, https://doi.org/10.1016/j.matdes.2013.08.045
• Smith, B., Szyniszewski, S., Hajjar, J., Schafer, B., & Arwade, S. (2012). Steel foam for structures: A review of applications, manufacturing and material properties. Journal of Constructional Steel Research, 71, https://doi.org/10.1016/j.jcsr.2011.10.028
• Smith, B., Szyniszewski, S., Hajjar, J., Schafer, B., & Arwade, S. (2012). Characterization of Steel Foams for Structural Components. Metals, 2(4), https://doi.org/10.3390/met2040399
• Szyniszewski, S., & Krauthammer, T. (2012). Energy flow in progressive collapse of steel framed buildings. Engineering Structures, 42, https://doi.org/10.1016/j.engstruct.2012.04.014
• Szyniszewski, S., Smith, B., Hajjar, J., Arwade, S., & Schafer, B. (2012). Local buckling strength of steel foam sandwich panels. Thin-Walled Structures, 59, https://doi.org/10.1016/j.tws.2012.04.014
• Szyniszewski, S., Akada, T., Masuya, H., & Kajikawa, Y. (2004). Numerical Simulation of a Concrete Plate subjected to Impact Load. Ouyou rikigaku rombunshuu, 7, https://doi.org/10.2208/journalam.7.635