Imprecise random field analysis for non-linear concrete damage analysis. (March 2021)

• Record Type: Journal Article
• Authors: Dannert, Mona M.; Faes, Matthias G.R.; Fleury, Rodolfo M.N.; Fau, Amelie; Nackenhorst, Udo; Moens, David
• Is Part Of: Mechanical systems and signal processing. Volume 150(2021)
• Publication Date: 2021-03
• Subjects: Uncertainty quantification -- Imprecise random fields -- Interval valued correlation length -- Karhunen-Loève expansion -- Non-linear stochastic finite element method -- Probability box approach; Structural dynamics -- Periodicals; Vibration -- Periodicals; Constructions -- Dynamique -- Périodiques; Vibration -- Périodiques; Structural dynamics; Vibration; Periodicals; 621
• DOI: 10.1016/j.ymssp.2020.107343
• Languages: English
• ISSNs: 0888-3270

Abstract

Highlights: Input material parameters are modelled as fields with uncertain correlation kernel. The correlation length is considered as an interval. The quantity of interest is described by a probability box (p-box). Uncertainty propagation of imprecise random fields is studied for non-linear behavior. The importance of intermediate correlation values within the interval is investigated. Abstract: Imprecise random fields consider both, aleatory and epistemic uncertainties. In this paper, spatially varying material parameters representing the constitutive parameters of a damage model for concrete are defined as imprecise random fields by assuming an interval valued correlation length. For each correlation length value, the corresponding random field is discretized by Karhunen-Loève expansion. In a first study, the effect of the series truncation is discussed as well as the resulting variance error on the probability box (p-box) that represents uncertainty on the damage in a concrete beam as a result of the imprecise random field. It is shown that a certain awareness for the influence of the truncation order on the local field variance is needed when the series is truncated according to a fixed mean variance error. In the following case study, the main investigation is on the propagation of imprecise random fields in the context of non-linear finite element problems, i.e. quasi-brittle damage of a four-point bended concrete beam. The global and local damage as the quantities of interest are described by a p-box. The influence of several imprecise random field input parameters to the resulting p-boxes is studied. Furthermore, it is examined whether correlation length values located within the interval, so-called intermediate values, affect the p-box bounds. It is shown that, from the engineering point of view, a pure vertex analysis of the correlation length intervals is sufficient to determine the p-box in this context.