A methodology for interpreting instrumented sharp indentation with dual sharp indenters with different tip apex angles is presented by recourse to computational modeling within the context of finite element analysis. The forward problem predicts an indentation response from a given set of elasto-plastic properties, whereas the reverse analysis seeks to extract elasto-plastic properties from dep...

The presliding displacement and stiction properties of friction models are investigated. It is found that existing single-state-variable friction models possess either stiction or presliding displacement. Next, those models with continuous states are interpreted as examples of Prandlt’s elasto-plastic material model. A class of general one-state models is derived that is stable, dissipative and...

This note presents an extension of the absolute stability problem and of the Lagrange–Dirichlet theorem, when the nonlinearities entering the model are considered within the class of monotone multivalued mappings (consequently including operators with piecewise-linear graphs that may represent physical e3ects like Coulomb friction, dead-zones, saturations, elasto-plasticity, and unilateral cons...

— Under some reasonable smoothness assumpfions on the displacements, we are able to dérive an error estimate of the form ||a — <7h||L2{fl)^ Ch, for the approximation of the stress field a in some problems in elasto-plasticity. Using the same ideas, we als o find a piecewise line ar approximation of Mosolov's problem, for which we still get an 0 (h) error estimate.

In this work, we present a deep neural network architecture that can efficiently surrogate classical elasto-plastic constitutive relations. The is enriched with crucial physics aspects of elasto-plasticity, including additive decomposition strains into elastic and plastic parts, nonlinear incremental elasticity. This leads to Physics-Informed Neural Network (PINN) model named here as Elasto-Pla...

The manipulation of microscopic objects is challenging because of high adhesion forces, which render macroscopic gripping strategies unsuitable. Adhesive footpads of climbing insects could reveal principles relevant for micro-grippers, as they are able to attach and detach rapidly during locomotion. However, the underlying mechanisms are still not fully understood. In this work, we characterize...

Abstract: The optimal control problems and a weight minimization problem are considered for elastic three-layered plate with inner obstacle and friction condition on a part of the boundary. The state problem is represented by a variational inequality and the design variables influence both the coefficients and the set of admissible state functions. We prove the existence of a solution to the ab...

Macroscopically heterogeneous materials, characterised mostly by comparable heterogeneity lengthscale and structural sizes, can no longer be modelled by deterministic approach instead. It is convenient to introduce stochastic approach with uncertain material parameters quantified as random fields and/or random variables. The present contribution is devoted to propagation of these uncertainties ...

Biomembranes shown to behave like elastic sheets, can also suffer plastic deformations. Neutron scattering experiments on partially polymerised wrinkled membranes revealed that when a critical degree of polymerisation is crossed, the wrinkled membranes do not resume their spherical shapes. Instead they remain wrinkled and rigid while their non-polymerised counterparts resume their spherical flo...