Digital image correlation in analysis of stiffness in local zones of welded joints

Ponašanje zavarenih spojeva u lokalnim zonama, kao i njihov uzajamni utjecaj, jedan je od glavnih problema u projektu zavarene konstrukcije. Naime, osnovni je problem u određivanju mehaničkih svojstava materijala u zavarenom spoju. Ta su svojstva neophodna za točan proračun zavarenih konstrukcija. Mogućnost dobivanja vrijednosti lokalne deformacije/pomaka čini tehniku "Digital Image Correlation" (DIC) pogodnom za ispitivanje zavarenog spoja i određivanje mehaničkih svojstava. Tijekom ovih ispitivanja za opterećenje je korišten uređaj za vlačnu provjeru, a dvije kamere su korištene za 3D analizu deformacije. Upotrijebljen je uzorak s paralelnim stranama dobiven zavarivanjem V spoja. Prije ispitivanja izvršeno je kalibriranje kako bi se dobili što točniji rezultati. U radu je predstavljena primjena DIC tehnike korištenjem Aramis softvera za mjerenje lokalnog pomaka/deformacije u zavarenom spoju. Dobiveni rezultati pokazuju da je zavareni spoj bio nejednako deformiran s prednje i zadnje strane korijena, u području elastične deformacije, tijekom vlačnog opterećenja. Zbog vlaka u uzorku s V-zavarom (osnovni materijal S235JRG2, žica elektrode - VAC 60), postoji uzajamni utjecaj mehaničkih svojstava lokalnih zona, gdje je krutost korijena zavara najviša.The behaviour of welded joints in local zones, as well as their mutual influence, represents one of the main challenges in welded structure design. Namely, the main issue lies in determining the mechanical properties of materials in a welded joint. These properties are necessary for an accurate calculation of welded structure integrity. The possibility of obtaining local strain/displacement values makes the "Digital Image Correlation" (DIC) technique suitable for welded joint testing and determining of mechanical properties. In this paper a tensile testing machine was used for loading and a two camera system was used for 3D strain analysis. A specimen with parallel sides, obtained by welding of a V joint was used. Calibration was performed prior to testing, in order to ensure dimensional consistency of the system. Application of DIC technique using Aramis software for measuring local displacement/strain in a welded joint is presented in this paper. Due to tension in the V-weld specimen (Base material - S235JRG2, electrode wire - VAC 60), mutual influence of mechanical properties of local zones is present, wherein the root weld had the highest stiffness

A Scalable Consent, Transparency and Compliance Architecture

In this demo we present the SPECIAL consent, transparency and compliance system. The objective of the system is to afford data subjects more control over personal data processing and sharing, while at the same time enabling data controllers and processors to comply with consent and transparency obligations mandated by the European General Data Protection Regulation. A short promotional video can be found at https://purl.com/specialprivacy/demos/ESWC2018