On the concrete material response to explosive loading - numerical simulations N. Gebbeken & M. Ruppert of Engmeermg Mec/zamc? aW Arwcfwra/ Mec/mm'cs

The development of material laws for concrete subjected to explosive loading which cause high pressure and extreme strain rates is a subject of current research. In some international codes for designing structural concrete the dependence of certain material properties, as strength in compression as well as tension and stiffness, on strain rates up to 10̂ [j] has already been introduced and is usually applied to conventional structural dynamics. An extrapolation of these dependencies for greater strain rates will not be appropriate. For the numerical simulation of the interaction between explosive loading and the structure a Hydrocode that enables the coupling of Lagrangian with Eulerian grids is used. In order to model the concrete behaviour realistically, appropriate constitutive laws, that enable to model the nonlinear viscous as well as the damage behaviour, have to be introduced. In addition, an equation of state has to be provided for the fulfilment of the conservation laws on which the Hydrocode is based on. To obtain the necessary material data, experimental investigations are indispensable. For that reason a series of field tests will be conducted in the near future. The specimen are reinforced concrete plates exposed to high explosive contact charges. Numerical simulations have been carried out in advance in order to prepare the experimental investigations. Transactions on the Built Environment vol 32, © 1998 WIT Press, www.witpress.com, ISSN 1743-3509 774 Structures Under Shock and Impact