Modelling of impact behaviour of concrete - An experimental approach

The last few years, explosion scenarios in tunnels and the potential hazards from storage of high energetic materials have received significant attention. Moreover, due to terrorist attacks, structures that can withstand explosions have become a major concern. For the modelling of the behaviour of concrete structures under the explosive loading conditions detailed knowledge on the material properties is essential.
Concrete is a rate-dependent material; the mechanical properties of concrete depend on the applied loading rate. Therefore, the mechanical response of concrete structures exposed to impact loading can only be predicted with proper material models that include the rate effects.
With the current computational facilities and the knowledge on computational modelling, force- and stress distributions can be calculated in concrete structures under complex dynamic loading conditions. However, material models that properly account for the true dynamic material response at meso- and micro level are still in their infancy. Consequently, these material models are the weak link in advanced finite element calculations. Reliable test data, that support modelling, are only available to a limited extent. The fracture energy has not been studied extensively yet and also data on the rate effect at very high strain rates are scarce. Without proper experimental data a new numerical material model cannot be validated.
This combined experimental and numerical study aims to understand the basic mechanisms that cause the rate effect, generate relevant experimental data and develop a proper numerical material model that includes the rate dependency of concrete under tensile loading.