PSI - Issue 19

Anne Coulon et al. / Procedia Structural Integrity 19 (2019) 665–673 Coulon / Structural Integrity Procedia 00 (2019) 000–000

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As part of the sensitive area evaluation phase, loads are extracted from EN 12 663 standard. Loads applied to the car body are: o Vertical +/- 0.18g for CITADIS 0.15g for MPL75, o Lateral +/- 0.15g, o Longitudinal +/- 0.2g. To identify the sensitive areas, several computation configurations are studied for each excitation direction considering the most severe connection between bogies and car body. It is noted that EN 12 663 standard specifies a durability of 10 7 cycles for each load direction. Fatigue stress limits of sensitive areas such as weldings are defined according to Eurocode 3 (2014), Eurocode 9 (2014) and IIW (2016). According to the fatigue stress analyses for each load case (Fig. 3), the sensitive areas are determined considering the cumulated damage of each load case. Rivet and screw fatigue behavior are also studied regarding loads transiting in them. All sensitive areas are listed from FE fatigue analysis and then inspected by an expert, see §3.1.2. From these results, the initial design is also criticized comparing the maximal stress computed to the nominal strength limit. This analyze corresponds to the second correction factor of the remaining life evaluation, see §2.

Theoretical Fatigue stress limit

Fig. 3. Stress map on CITADIS for vertical load.

3.1.2. Inspection Inspection of sensitive areas is done by an expert from the Institut de Soudure. Visual and nondestructive examinations are done in each sensitive area indicated on 3D, see Fig. 4. Potential cracks are detected (see Fig. 5.) and their criticality is evaluated regarding their propagative status. The strength limits considered in the initial design are updated and criticized regarding the manufacturing quality of welds and their current status in the sensitive areas (C 3 coefficient).