Reducing Model-Discrepancy in High-Fidelity Structural Simulators Using Advanced Nonlinear Theories for Digital Twinning

The mechanical modelling of masonry systems is notoriously challenging due to the wide behaviour that such structures can exhibit when subjected to random external forcing. Several laws have been proposed in the past for this purpose, with the result, however, of being: (i) too accurate of a specific structural behaviour, with the risk of losing the physical meaning or overfitting the experimental data; or on the contrary (ii) too approximate, which, even if efficient, only able to capture some global characteristics of the mechanical behaviour. In the present work, the authors propose the use of a recent continuum theory, which instead of describing the structural problem in differential form, uses nonlinear integral-differential equations of motion having a limited number of mechanical parameters. This continuum theory, called Peridynamics, however, when used in a discrete sense must be corrected in order to reduce the discrepancy that arises in approximating the continuity of the body. In the present study, the authors propose a method to overcome this discrepancy that arises in using low resolution simulators instead of high-resolution ones.