Divya Varkey successfully defended her PhD thesis!

Divya Varkey, postdoctoral researcher in the section of Geo-Engineering, successfully defended her PhD thesis entitled “Geotechnical uncertainties and reliability-based assessments of dykes”, on 24 September 2020.

 

The thesis uses the random finite element method (RFEM) to provide practical guidance and tools for geotechnical engineers to account for the influence of soil spatial variability. This has mainly involved: practical insight and guidance on the choice of characteristic soil property values and scales of fluctuation; a robust approach to reliability-based assessment and design of dykes that obviates the need for explicit calculation of characteristic values; and the benchmarking and improving of simpler analysis tools.

In particular, this thesis demonstrates the advantages of accounting for spatial variability of shear strength parameters in the 2D reliability-based assessment and re-designing of an existing dyke in the Netherlands. The thesis further extends the research by investigating the relative influence of uncertainties in geometry and spatial variability of shear strength properties in the third dimension on the responses of an idealised 3D embankment slope, demonstrating the significant influence of the latter and thereby proposes a worst-case correlation length. Furthermore, considering the large computational requirements for RFEM, the thesis benchmarks and updates a semi-analytical method to get results comparable with RFEM for idealised 3D embankment slopes.

Divya is originally from India. She did her BSc at the College of Engineering Trivandrum in India and MSc at the Indian Institute of Technology Roorkee in India. Before moving to the Netherlands in 2015, she spent few months at the University of Stuttgart in Germany to carry out her master thesis under the DAAD-IIT master sandwich programme. She is currently working as a postdoctoral researcher in the Section of Geo-Engineering, continuing the research from her PhD and extending the application to various problems. 

Divya's thesis can be found here.