Author(s)

R. Schmidt & M. Stoffel

Abstract

This paper deals with experimental investigation, modelling, and simulation of plates subjected to blast loading conditions. Experiments are performed on thin clamped circular aluminium plates in a shock tube. The main advantage of this experimental technique is that the front wave impinging on the structure is plane and yields a uniformly distributed pressure pulse. The non-linear shell theory of Schmidt and Reddy [1] is used as a basis of a finite element algorithm for the simulation of the transient, geometrically non-linear elastic-viscoplastic response. Numerical solutions are obtained by using the isoparametric Lagrangian 9-node shell finite element and the central difference method for the time integration of the non-linear equations of motion. Special emphasis is focused on the evolution of deflections, bending moments, membrane forces, and equivalent plastic strain rates under blast loading conditions. The obtained results allow for an explanation of the evolution of the experimentally observed final conical shape by flexural waves which originate at the boundary and travel towards the plate centre at different speeds. Keywords: blast loading, shock tube, viscoplasticity, vibrations, plates. 1 Introduction Experimental investigations of structures subjected to blast loading conditions are frequently performed by shock waves generated by explosives (e.g. gaseous mixtures, charges of plastic explosives) that detonate at some distance of the structure (see Idczak et al. [2, 3], Renard and Pennetier [4], Pennetier [5], among others). These experimental techniques lead to a complex non-uniform timespace evolution of the pressure distribution on plane structural elements thus

Keywords

blast loading, shock tube, viscoplasticity, vibrations, plates.