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IRIS_2010 benchmark was an exercise in OECD/NEA/CSNI framework. This exercise concentrated on improving robustness assessment methodologies for structures impacted by missiles. This article describes experimental tests included in the exercise. These tests consisted of two tests for bending, three for punching and one for combined punching and bending behaviour of reinforced concrete walls under impact loading. The test for combined behaviour was carried out in Meppen, Germany in the 1980’s, while all the other tests were carried out by VTT Technical research centre of Finland during the spring of 2010. In the bending behaviour tests, 0.15 m thick simply supported square concrete walls with span width of 2 m were impacted with soft missiles weighing ∼50 kg and having velocity of ∼110 m/s at the impact moment. The impacts resulted maximum displacements of 29-32 mm at the centre of the wall with the permanent values being 8-9 mm. In the punching behaviour tests, similar walls but with thickness of 0.25 m were impacted with hard missiles weighing ∼47.5 kg and having velocity of ∼135 m/s at the impact moment. The impacts resulted perforation of the wall by the missile with residual velocity of the missile being 34-46 m/s. In addition, the walls suffered severe scabbing on the backside with the scabbed area being 1.00-1.12 m2.

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Modelling and analysing fires following aircraft impacts requires information about the behaviour of liquid fuel. In this study, we investigated sprays resulting from the impacts of water-filled metal projectiles on a hard wall. The weights of the projectiles were in the range of 38…110 kg, with 8.6…68 kg water, and the impact speeds varied between 96 and 169 m/s. The overall spray behaviour was observed with high-speed video cameras. Ultra-highspeed cameras were used in backlight configuration for measuring the droplet size and velocity distributions. The results indicate that the liquid leaves the impact position as a thin sheet of spray in a direction perpendicular to the projectile velocity. The initial spray speeds were 1.5…2.5 times the impact speed, and the Sauter mean diameters were in the 147…344 mm range. This data can be used as boundary conditions in CFD fire analyses, considering the two-phase fuel flow. The overall spray observations, including the spray deceleration rate, can be used for validating the model.

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