Nicolas Gayton

• Sigma Clermont

In a context of uncertainty quantification, the probabilistic model of a random vector at the input of a computational code is not always known. An identification of the joint distribution on a restricted sample of experimental data can lead to a bad calibration of the model. The quantity of interest estimated at the output of the code is then subj...

Metrology is extensively used in the manufacturing industry to determine whether the dimensions of parts are within their tolerance interval. However, errors cannot be avoided. Metrology experts are of course aware of it, and able to identify the different sources that contribute to making errors. In this paper, the probability density function of...

The optimal design of complex engineering systems is a necessary task in a challenging industrial environment. Constrained optimization frameworks properly take charge of the engineering requirements by considering uncertainties in the constraint and identifying the optimal compound of design parameters among the admissible ones. However, this proc...

Metrology tools are applicable to check whether dimensions lay within their tolerance intervals. However, measurement errors cannot be avoided. This paper develops a method to partially correct the effect of such errors in case their probability density function is known. We assume that the probability density function associated with the measured...

Despite the computing power achieved with current technologies, computationally intensive analyses (e.g. optimization problems, reliability or sensitivity analyses) actually remain a time-consuming problem in modern engineering. Traditionally, a widely used approach to deal with this issue based on learning from data, relies on metamodels or surrog...

Rib-to-deck connections are one of the most critical fatigue-prone locations in orthotropic steel decks. Initiated cracks in the root of a fillet weld in this location can propagate towards the deck plate due to the existence of transversal tension within the deck plate near the cracking area. Such cracks can put the structure in a very critical si...

Metrology is extensively used in the manufacturing industry to determine whether the dimensions of parts are within their tolerance interval. However, errors cannot be avoided. If the metrology experts are actually aware of it, and currently able to identify the different sources that contribute to making errors, very few research has been made in...

This chapter considers a probabilistic framework for the input uncertainty modeling assuming sufficient information is available to construct a relevant input probabilistic model. It focuses on a specific class of reliability‐oriented sensitivity analysis (ROSA) methods and its extension to reliability problems involving two uncertainty levels in i...

This chapter provides a fairly brief overview of recent adaptive methods for calculating failure probabilities based on the use of Kriging with a focus on so‐called active learning and Kriging‐based method (AK) methods. The common feature of simulation methods is the need to classify points according to the sign of the performance function. These m...

Computing the cumulative failure probability for a given period of time is the main goal of a time-dependent reliability analysis. Estimating this probability is challenging for problems with nonmonotonic performance functions, especially when they are costly to evaluate and have high dimensionality. Discretizing the time interval is one main step...

Considérer le contexte incertain en ingénierie mécanique dans le but d’améliorer les performances des futurs produits ou systèmes apparaît désormais comme un avantage compétitif, voire une nécessité pour garantir une exigence de sûreté de plus en plus élevée. Ingénierie mécanique en contexte incertain traite de la modélisation, de la quantification...

Considérer le contexte incertain en ingénierie mécanique dans le but d’améliorer les performances des futurs produits ou systèmes apparaît désormais comme un avantage compétitif, voire une nécessité pour garantir une exigence de sûreté de plus en plus élevée. Ingénierie mécanique en contexte incertain traite de la modélisation, de la quantification...

During the design stage of product manufacturing, the designers try to specify only the necessary critical dimensions or what is called “Key Characteristics”. Knowing that dealing with Key Characteristics is time consuming and costly, it is preferable to reduce their number and exclude the non-contributing parameters. Different strategies that are...

Le vieillissement des conduites forcées d'amenée d'eau aux centrales hydroélectrique entraine une diminution de l'épaisseur de celles-ci par corrosion. Le scénario redouté correspond à la rupture entre deux années successives d'une conduite sachant que l'épreuve hydraulique lors de sa mise en service était réussie. Pour calculer cette probabilité a...

Lifetime damage estimation is a complex and demanding task that needs to be performed during the design of offshore wind turbine structures. A general damage analysis framework is proposed by the certification bodies. Therein the total lifetime of the structure is considered as a series of elementary situations combining structural and environmenta...

Reliability analyses still remain challenging today for many applications. First, assessing small failure probabilities is tedious because of the very large number of calculations required. Secondly, mechanical system models can require considerable numerical efforts. To deal with these problems, classical reliability analysis methods may be combin...

Variabilities in geometrical and material properties occur systematically after manufacturing and joining operations on different parts of an assembly. The behaviour and structural performance of composite/composite or composite/metal fastened joints are particularly sensitive to some of these variabilities. Controlling the effect of variabilities...

After a review of main tolerancing calculation methods, we defend several key concepts toward process tolerancing approach: 1) there is no interrest to produce green stackups with wrong process hypothesis: the right approch is to integrate the truth of the process early 2) The data may travel faster than the trucks. If the design office share its...

Offshore wind energy development has experienced a rapid development over the last few years encouraged by the of carbon reduction policy and the energy mix objectives of several countries worldwide. Nowadays, the offshore projects under investigation are composed of tens to hundreds of units reaching impressive dimensions with total rotor diameter...

The aim of this paper is to provide an overview of a developed statistical tolerance analysis technique for over-constrained mechanism. Statistical tolerance analysis is a more practical and economical way of looking at tolerances and works on setting the tolerances so as to assure a desired functionality; however, most of statistical tolerance ana...