Effect of noise in the time-frequency estimate of the peridynamic bond elastic constant parameter

The Peridynamic (PD) theory is a modern nonlocal (nonlinear, elastic /inelastic, with-out/with me...mory) theory able to deal with long-range forces and discontinuity in materials. For this reason the theory is suitable for the monitoring of masonry structures. Starting from a special case of PD formulation, named Bond-Based Peridynamic (BBPD), a feature ob-tained by the idealization of real systems with BBPD is used for SHM purposes: the bond elastic constant parameter. To characterize the damage (i.e. permanent deterioration of ma-terial and/or geometric properties of the systems) occurring in systems idealized with PD models, a joint time-frequency direct estimate of the parameter values is performed using a Short Time Fourier Transform (STFF) of the systems response and the input acceleration at the base of the systems. The method is applied numerically and the effect of noise in the time-frequency evaluation of the parameter values is analyzed. The study concludes that PD can provides simply and strong information on the health of simulated systems, allowing at the same time an easy and scalable parametrization of civil, especially masonry, structures, while the bond elastic constant parameter can be used for the damage characterization, i.e. to detect, quantify and localize the damage in a generic system.