## 3 3D DIC in Blast and Shock Loading
By calculating the material models off the opposite sides of the windows on those experiments, the authors were able to determine the material properties. Their results show that the majority of the blast energy is reflected back in the direction of the blast origin or vented around the structure, with only 6.8% transferred to the system and 3.1% absorbed by material failure, leading to the conclusion that the absorption capability of the system is relatively small, compared to the energies which are potentially applied to it. The authors show that the post-cracked reaction reached a distinct plateau as the central deflections increased. [PERSON] et al. postulate that this could be caused by delamination between the PVB interlayer and the outer glass plies [53]. [PERSON] et al. [54] examined the response of steel containers to an internal cylindrical explosive charge. The steel containers had dimensions of 1 m \(\times\) 1 m \(\times\) 1 m, with a wall thickness of 5 mm. The containers had two variants, one with a flange that can be bolted to a solid base and a fully enclosed variant. The flanged container had one open end and a 10 mm thick flange, which the authors bolted to a non-responding steel plate secured to a concrete block. The flange was welded to the side of the 5 mm thick container wall using a 10 mm thick reinforcing square section, which was welded on the outside corner of the container in the interface between the container and flange. The fully enclosed containers were not bolted down, but instead suspended on wooden blocks. The explosive was uncased PE4 plastic explosive with a length/diameter ratio of 1 and a mass of between 245 g to 431 g. The DIC imagery was taken at 7000 FPS, but the authors did not specify the specific model of camera used. The authors used the ARAMIS software (GOM GmbH, Braunschweig, Germany) package to process the high-speed imagery. Most of the containers experienced failure around the welded joint from weld tear initiation observed during the initial expansion of the container. In the majority of experiments the authors reported on, the container would reach maximum deformation, then contract, and during a second expansion, the initial weld tear would propagate along the welded joint, resulting in the catastrophic failure of the container. In the experiments with the largest charge mass, their results show the initial weld tear and subsequent weld tear propagation occurred prior to the container reaching maximum deformation. Failure in those cases occurred due to the applied load significantly overmatching the strength of the welded container. [PERSON] et al. reported on the strain measurements recorded using the DIC. The authors show that the strain profiles were consistent for all events, with only the maximum strain values differing. The authors show that the highest strains were observed at the edges of the container in the welded joints for all events. The second highest regions of strain were located on the face of the container. The region of highest deflection, the centre of the face, recorded the lowest strain. The strain rate was approximately an order of magnitude greater on the weld joint to the face of the container [54]. [PERSON] et al. [55] examined the response of thin circular plates to confined explosions. The circular plates were made from ASTM C11000 copper, h62 brass or \(\alpha\)-titanium alloy (Ti 50A). All of the plates were tested with a 2 mm thickness, with the copper also being tested with 3 mm thickness. The explosive was a desensitised RDX plastic explosive, with a mass ranging from 3 to 4 g and a diameter of 20 mm. The explosion was confined in a small-scale stainless-steel cylinder with the test plates bolted onto one end and the other end being welded closed. The authors used a pair of Photron Fastcam SA5 cameras (Photron USA, Inc., San Diego, CA, USA) running at 50,000 FPS to capture the high-speed imagery. The images were processed with the VIC-3D software (Correlated Solutions, Inc., Irmo, SC, USA).