­Congratulations to Ms Alaleh Shehni on the successful defence of her doctorate

On September 30, 2020, Alaleh Shehni M. Sc. successfully defended her scientific work within the scope of her doctoral thesis on "Modeling of strain-hardening cement-based composites (SHCC): A finite element method using the strong discontinuity approach (SDA) with explicit representation of fibers".

Strain-hardening cement-based composites (SHCCs) is a particular class of fiber reinforced concretes (FRCC) that can develop controlled multiple cracks while subjected to incremental tensile loading conditions.

However, a proper composition design, especially concerning fiber and bond properties, still follows a trial and error approach.

Alaleh´s work presents a newly developed model to simulate SHCC at the messcale level. This model is based on Finite-Element-Method and allows for nonlinear behavior for cement matrix, fiber material, and bond laws. while it is considering three complexities of target FRCC, i.e., crack formation in the cement matrix, a large number of explicit fibers with arbitrary random distribution, and fibers' interaction with the cement matrix via the bond.

in the end, a series of numerical case studies were performed to assess the quality, credibility, and limitations of the numerical model. ​

In addition to the chairman of the PhD Commission, Prof. Dr.-Ing. Steffen Marx (DB Netz AG - Endowed Professorship for Civil Engineering, TU Dresden), Prof. Dr.-Ing. habil. Ulrich Häußler-Combe (Institute for Concrete Structures, TU Dresden), Dr.-Ing. Christina Scheffler (Leibniz Institute for Polymer Research e.V., Dresden), Prof. Dr.-Ing. Stefan Löhnert (Institute for Mechanics and Shell Structures, TU Dresden) and Prof. Marco Di Prisco from the Dipartimento di Ingegneria Civile e Ambientale at the Politecnico di Milano (via live video link) were present as members of the PhD Commission. The research work was carried out within the framework of DFG-GRK 2250 "Mineral-bonded composites for enhanced structural impact safety".

We congratulate Alaleh Shehni on her doctoral degree and wish her all the best and every success in her future career.