%0 Journal Article %1 sriram_transient_2021 %A Nirupama Sriram, Siddharth %A Polukhov, Elten %A Keip, Marc-André %D 2021 %J International Journal of Solids and Structures %K EXC2075 PN3 PN3-5 curated %P 111080 %R https://doi.org/10.1016/j.ijsolstr.2021.111080 %T Transient stability analysis of composite hydrogel structures based on a minimization-type variational formulation %U https://www.sciencedirect.com/science/article/pii/S0020768321001700 %V 230-231 %X We employ a canonical variational framework for the predictive characterization of structural instabilities that develop during the diffusion-driven transient swelling of hydrogels under geometrical constraints. The variational formulation of finite elasticity coupled with Fickian diffusion has a two-field minimization structure, wherein the deformation map and the fluid-volume flux are obtained as minimizers of a time-discrete potential involving internal and external energetic contributions. To analyze the structural stability of a certain equilibrium state of the gel satisfying the minimization principle, we apply the local stability criterion on the incremental potential, which is based on the idea that a stable equilibrium state has the lowest potential energy among all possible states within an infinitesimal neighborhood. Using this criterion in a finite-element context, it is understood that bifurcation-type structural instabilities are activated when the coupled global finite-element stiffness matrix loses its positive definiteness. This concept is then applied to determine the onset and nature of wrinkling instabilities occurring in a pair of representative film-substrate hydrogel systems. In particular, we analyze the dependencies of the critical buckling load and mode shape on the system geometry and material parameters.

@article{sriram_transient_2021, abstract = {We employ a canonical variational framework for the predictive characterization of structural instabilities that develop during the diffusion-driven transient swelling of hydrogels under geometrical constraints. The variational formulation of finite elasticity coupled with Fickian diffusion has a two-field minimization structure, wherein the deformation map and the fluid-volume flux are obtained as minimizers of a time-discrete potential involving internal and external energetic contributions. To analyze the structural stability of a certain equilibrium state of the gel satisfying the minimization principle, we apply the local stability criterion on the incremental potential, which is based on the idea that a stable equilibrium state has the lowest potential energy among all possible states within an infinitesimal neighborhood. Using this criterion in a finite-element context, it is understood that bifurcation-type structural instabilities are activated when the coupled global finite-element stiffness matrix loses its positive definiteness. This concept is then applied to determine the onset and nature of wrinkling instabilities occurring in a pair of representative film-substrate hydrogel systems. In particular, we analyze the dependencies of the critical buckling load and mode shape on the system geometry and material parameters.}, added-at = {2024-07-15T19:01:06.000+0200}, author = {Nirupama Sriram, Siddharth and Polukhov, Elten and Keip, Marc-André}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2c27d1cef653f95e1dd5bf65a73339031/simtech}, description = {Transient stability analysis of composite hydrogel structures based on a minimization-type variational formulation}, doi = {https://doi.org/10.1016/j.ijsolstr.2021.111080}, interhash = {ce1d4bfc34163479887b569f985a3575}, intrahash = {c27d1cef653f95e1dd5bf65a73339031}, issn = {0020-7683}, journal = {International Journal of Solids and Structures}, keywords = {EXC2075 PN3 PN3-5 curated}, pages = 111080, timestamp = {2024-07-19T15:09:42.000+0200}, title = {Transient stability analysis of composite hydrogel structures based on a minimization-type variational formulation}, url = {https://www.sciencedirect.com/science/article/pii/S0020768321001700}, volume = {230-231}, year = 2021 }