PSI - Issue 17

Tamás Fekete / Procedia Structural Integrity 17 (2019) 464–471

469

Tamás Fekete / Structural Integrity Procedia 00 (2019) 000 – 000

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4. Structural Integrity as a scientific-engineering paradigm

Nowadays it is hard to give a concise, unambiguous definition to Structural Integrity. As formulated in the mission statement of ESIS (2019): ’ Structural Integrity … refers to the safe operation of engineering components, structures and materials, and addresses the science and technology that is used to assess the margin between safe operation and failure ’ . As it was explained earlier, the meaning of the phrase Structural Integrity for a functioning System is to achieve a more realistic assessment for its ‘ technically allowed lifetime ’. When it comes to choosing the more reliable method that should be used for Structural Integrity assessments of actual Systems, we reach the methodology issue of Structural Integrity. In this context, can we talk about Structural Integrity as a scientific-engineering paradigm . According to the explanation of OED (2019), the word paradigm has two different, but closely related meaning: • ‘ A typical example or pattern or model of something . ’ • ‘ A world view underlying the theories and methodology of a particular scientific subject ’ , … which ‘are more than theories; they are conceptual frameworks that define a field of study ,’ and guide ‘conception of reality ...’ If the phrase ‘ Structural Integrity as a scientific-engineering paradigm ’ is used in the sense of a ‘typical example or pattern’ of achieving correct values for the ‘ technically allowed lifetime ’ of a System, then the methodological questions can be interpreted as suggested by the use of standards or best practices guides. If the phrase ‘Structural Integrity as a scientific- engineering paradigm’ is interpreted in line with the second explanation above, then we arrive at the fundamental question of the subject: from which basic ideas, and how is it possible to find a physical theory that can serve as the future background-theory for Structural Integrity? As background-theory we mean a physical theory from which the methodologies of Structural Integrity assessments for a System can be coherently determined. Taking the aforementioned considerations into account, we have developed the General Conceptual Model of Structural Integrity , which was first published in more detail in Fekete (2018) and in the references therein. The General Conceptual Model of Structural Integrity integrates all fundamental aspects that nowadays play a major role in solving Structural Integrity problems of a System. The fundamental aspects are as follows (see Fekete (2018)): • Theoretical aspect that includes the theoretical, the methodological and the numerical matters, such as: ○ Physical theory (the general discipline of the subject); ○ Effective physical model (methodological matters); ○ The actual model of a particular structure/system. • Analysis aspect that describes the safety computations on the actual model of a particular system, with: ○ Description of the initial conditions of the structure/system; ○ Description of the time evolution of the working technology; ○ Description of the time evolution of the various external – loading and environmental – conditions. • Experimental aspect, which describes the data provided by the MSIT system, as follows: ○ Results of material testing programs; 4.1. The General Conceptual Model of Structural Integrity

○ Results of non-destructive examination programs; ○ Results of in-service measurement programs. • IT aspect, which assists the realization of the analyses by:

○ Realization of computations and their evaluations, as well as storing the calculation results; ○ Collecting the time- series of loads and environmental factors, and ‘memorizing’ them; ○ Supporting the measurements and their evaluation.

A hypergraph model was developed based on this description (see on Fig.1.). The model follows the concept of typed graph grammars that makes the relations between various aspects intuitively understandable, and additionally, it is a mathematically sound concept. More details can be found in Fekete (2018) and in the references therein.