Sensitivity studies on a punching wall of IRIS_2010 benchmark exercise

A case study in the IRIS_2010 benchmark exercise in the OECD/NEA/CSNI/IAGE framework covered a reinforced concrete wall subjected to impact by a hard steel missile with a mass of 47 kg and an impact velocity of 135 m/s. The considered simply supported square slab was 2 m wide and 25 cm thick. The expected and realized collapse mode was perforation. Tests were carried out with a VTT impact test facility. A VTT team also participated in the blind benchmark exercise. Analyses were carried out using a one-dimensional penetration/perforation model and the Abaqus/Explicit Finite Element (FE) program. Selected calculation results were presented at the IRIS_2010 Workshop. Based on Workshop presentations and discussions it was concluded that the nonlinear analysis of reinforced concrete structures is a challenging task and calculation results are quite sensitive, e.g., to material parameters and modeling assumptions. Various sensitivity studies of this so-called punching test were carried out afterward, and results are presented and discussed in this paper. Overall, results obtained with both the simplified method and the FE method are in relatively good agreement with test results.