Back Elham Alizadeh


Biomechanics & Mechanobiology, SIMBIOSys
Postdoctoral Researcher

I completed the B.Sc. in civil engineering [2007-2011] and the M.Sc. in structural engineering [2011-2013]. In my M.Sc., I performed static experimental tests to evaluate the behavior of composite decks. Using Ansys software, I numerically validated my finite element models with my experimental results in composite bridge decks to propose new composite decks with a high strength-to-weight ratio. The results of the master project conducted on bridge decks were published as my first journal paper (Alizadeh, E, Dehestani, 2015) in Structural Engineering and Mechanics (JCR 2023 - Impact factor: 2.2-Q2). Besides, the results of the master's thesis led to a patent (Alizadeh, E., Dehestani, M., Navayi Neya, B., Moslemi Vareki, A).

After my M. Sc., I wrote my first research proposal to apply for a research grant. The research proposal was successful, I received the funding and I became a research team member (2013-2018) in which we experimentally and numerically worked on hollow lightweight composite decks with different types of concrete slabs in compression zones and different shear connectors. The slippage and debonding between constituents of composite bridge deck are investigated in experimental tests and are employed in finite element analysis (FEA). The results of the project conducted on bridge decks led to two journal papers (Alizadeh et al., 2019) and (Alizadeh & Dehestani, 2019) which were both published in the Journal of Sandwich Structures & Materials (JCR 2023 - Impact factor: 3.9-Q1). 

In my PhD [2015-2020], I spent the doctoral fellowship in Prof. Zysset’s research group, who has more than 25 years of experience in bone research, at the University of Bern, Switzerland. I conducted a part of my PhD thesis at Bern University and I continued working on PhD project under the guidance of him until the end of the project. I numerically and theoretically studied the bone nano-composite mechanical properties in my PhD dissertation. In the PhD project, I worked on multi-scale modeling of bone material at nano and micro scales, and a representative volume element of bone at these scales is presented. Three finite elements (FE) unit cells with periodic boundary conditions are presented to model a two-scale microstructure of bone. The axial and transverse orthotropic elastic properties of the model were numerically calibrated with novel experimental results using the recent micro-tensile and micropillar compression tests in both axial and transverse directions performed in our research group in Bern University and Empa, Switzerland. The axial and transverse elastic modulus of the model are then systematically calculated using analytical methods. The predicted axial strain ratios between the two scales are compared with recent small-angle X-ray scattering and wide-angle X-ray diffraction studies. The study mentioned above (Alizadeh et al., 2020) has been published in Biomechanics and modeling in mechanobiology journal (JCR 2023 - Impact factor: 3.5-Q1).

As my second experience in writing a research proposal, I have designed and been the main author of a successful scientific multidisciplinary proposal and applied for a research grant [2017-2018].  I worked analytically and numerically on a research project using fracture mechanics theory and the extended finite element method (XFEM) in a pressure vessel containing a crack. In the project, the elastic and elastic-plastic fracture mechanics theories using the Irwin model are utilized to calculate the critical internal pressure of vessel including cracks. Besides, the loading capacity of the model containing an inclined crack is analytically calculated under modes I and II of fracture. The XFEM method is utilized for modeling the crack propagation and investigating the effects of multiple cracks along the vessel’s circumference, crack width, crack location on the internal or external edge of the vessel, and applying the FRP laminates to reinforce the vessel. The research project led to a paper (Alizadeh & Dehestani, 2018) in Thin-Walled Structures (JCR 2023 - Impact factor: 6.4- Q1).

I planned, organized, and wrote my third research proposal to apply for the competitive postdoctoral position supported by the Swiss Government. The proposal was successful and I held a Swiss Government Excellence Scholarship (FCS) for postdoc at Bern University in [2021-2022]. Besides, I collaborated remotely with researchers at Brunel Composites Centre (BCC), Brunel University London, UK.

I investigated the post-yield behavior of bone using 3D non-linear finite element analysis and I also worked on Rheological models. For the first time, the behavior of bone at the micro-scale is investigated in Prof. Zysset’s research group using micropillar compression and micro tensile tests at two longitudinal and transverse directions (Casari et al., 2021), (Schwiedrzik et al., 2014b). In the post-doc project, damage accumulation and strength of the calibrated FE models at the ECM scale are numerically studied in tension and compression in two axial and transverse directions concentrating on matrix-fiber interfaces. The plasticity of the material is defined with UMAT (Using Python code) and the cohesive interaction is utilized to model the sliding and debonding of constituents. For the first time at the micro scale, the numerical results fit excellent with experimental results and demonstrate the failure mechanism of bone at the micro level in two axial and transverse directions and under tensile and compressive loading. The results are published (Alizadeh et al., 2023) in the Journal of Mechanical Behavior of Biomedical Materials (JCR 2023 - Impact factor: 3.9- Q1).

I was a supervisor of several interdisciplinary M.Sc. Projects. One of our M.Sc. projects is related to the current research proposal entitled "Multi-Scale Modeling of Concrete Containing Recycled Aggregates" in which we used analytical and FE homogenization methods to investigate the multi-scale elastic properties of concrete containing recycled aggregates at meso and macro scales. The results are published (Hosseinzadeh et al., 2022) in Construction and Building Materials (JCR 2022 - Impact factor: 7.69-Q1).

I started teaching after graduating with my M.Sc. and I also was an assistant professor at Arak University, Iran [2022-2023]. I taught "Fracture Mechanics", "Mechanics of Composite Materials", "Statics", "Dynamics", "Strength of Materials", "Solid Mechanics", "Continuum Mechanics", "Advanced engineering mathematics", "Steel Structures" and "Concrete Structures" courses for almost 10 years.

All in all, I have teaching experiences, theoretical and numerical research experience in multi-scale modeling of biomaterials and composite materials, interdisciplinary research experience in musculoskeletal biomechanics and composite structures, nonlinear FE modeling skills as well as fracture mechanics knowledge, FE experience in evaluating the fiber-matrix interfaces, the analytical experience in homogenization methods, and experimental experience in thesis and research projects.  

Currently, I am working on a 3D FE model extracted from DXA scans to predict femur fracture. The research aims to develop a FEA module for 3D-Shaper that will enable QCT-equivalent bone strength estimations from DXA scans. The 3D-Shaper FEA module will be used to evaluate the effect of pharmacological treatments, enabling clinical trials with a reduced economic cost and without performing CT scans.