Monitoring and compartmentalized structures

Abstract

The damage acting on a structure can lead to disproportionate consequences, i.e., the global collapse. This extreme situation has to be avoided and, thus, structural monitoring is requested in those structures where human losses are possible and large economic consequences are expected. Static measurement devices are the most economic instrumental set‐ups able to highlight the presence of progressive damages. However, this monitoring system suffers from the structural behaviour under the external loads. In many situations, alternate load paths shown the non‐effectiveness of the measurement system since the instrumentation are installed on elements not relevant for the response under the given loads. The same problems occur when the structure is compartmentalized, i.e. the structural responses of the single parts dependent on the loads acting almost only on the same single component. In order to measure the degree of compartmentalization, different novel metrics based on stiffness matrix properties are proposed and their effectiveness discussed. The new idea of this paper is to connect compartmentalization of structures with a sort of distance of the stiffness matrix from the set of diagonal matrices. Few examples are illustrated.

Generalized Bessel Functions in Terms of Generalized Hermite Polynomials

“…Still, there is room for further investigations this wide scenario offered by the nature of the Hermite polynomials. Furthermore, the generalized Hermite polynomials and the related special polynomials, cited above as Laguerre, Legendre and Chebyshev polynomials and different families of special functions, in particular the large class of functions recognized as belonging to the Bessel functions, can be efficiently employed to solve a large class of problems in field such as stochastic processes [21][22][23], particle physics [24,25], electromagnetisms [26][27][28], continuum mechanics [29,30], material sciences [31,32], transmission lines [33][34][35], building sciences [36][37][38] and applications in the field of special functions and orthogonal polynomials [39][40][41][42][43][44]. Further investigations will be carried out in the next future in other fields of interest.…”

Damage tolerance in parallel systems

“…A simple structure is the one that has a reduced number of effective load paths. On the contrary, when all the possible load paths are equally effective, the structure reaches its maximum complexity (Cennamo et al, 2014;De Biagi and Chiaia, 2013). As a matter of evidence, in statically determinate structures, like a cantilever, the load path is unique.…”

Implementation of Progressive Damage in Finite Element Codes for the Assessment of Robusntess

“…The robustness of concrete buildings subjected to element removal has been usually assessed through numerical, experimental and analytical strategies (see, for example, [16,17,18]). In addition, theoretical [19,20,21,22] and probabilistic approaches [23,24,25] as well as scenario analyses have been already formulated and proposed [26].…”