Стипендия за докторантура-Германия:спец. физика, прил.матем

[MariaD]

URGENT!
F.A. Finger Institute for building materials science
(Faculty of civil engineering)
Bauhaus-University Weimar, Germany
offers a:
Full position for PhD thesis funded by German Science foundation (DFG) within the
research training group 1462 on the topic:
“Model validation in structural engineering“
Subject:
Imaging of microstructure and texture in porous materials in constitutive
relation – quality requirements for partial models within a model chain
Supervisors: Dr. B. Möser / Prof. J. Stark, Prof. T. Schanz, Dr. M. Datcheva
The study intends to reveal the influence of texture on the material models of porous
materials (concrete). Texture will be measured and modelled in dependence of scale. The
project deals with the consequence of texture on quality of material models on different
scales (particle methods, DEM, discrete points at continuum mechanics view). Especially the
influence of texture on scale transition has to be analysed, i.e. on the view of numeric
homogenisation. It has to be checked how textures are already included in current models of
cement and concrete hardening. Criteria have to be defined that indicate if texture has to be
implemented in the mechanical model. The various approaches have to be calibrated and
verified against experimental data (imaging of texture).
Furthermore the treatment of texture with regard to initial-boundary value problems has to be
investigated. The question arises if their consideration is significant for the quality of the
model. Furthermore smeared models have to be compared to scale models.
Imaging methods like electron microscopy allow us to characterize and quantify the
microstructure of concrete from aggregate scale down to the meso gel pores, i.e. nanometre
scale. Micro mechanic experiments under cyclic tensional and compressional loading in the
environmental scanning electron microscope visualize the cracking behaviours of concrete.
Thus the crack propagation on the meso- and nanoscale can be imaged under close-tonative
conditions. Further micro mechanical parameters (elastic modulus) of concrete should
be measured by nanoindentor experiments.
Please submit your application including CV to:
Prof. Tom Schanz,
Bauhaus-University Weimar
Faculty of Civil Engineering
Coudraystr. 11
D-99421 Weimar, Germany
Tel. +49 (0) 3643 – 584558
e-mail to: tom.schanz@uni-weimar.de