Zusammenfassung
This paper continues studies in Lalegname et al. (Int J Fract 152:97--125,
2008 ) on crack propagation in a bounded linear elastic body under
the influence of incident waves. In Lalegname et al. ( 2008 ) we
have considered shear waves, whereas in this paper we discuss the
influence of plane elastic waves to a running crack. Actually, the
time dependent problem is formulated in a two-dimensional current
cracked configuration by a system of linear elasto-dynamic equations.
In order to describe the behaviour of the elastic fields near the
straight crack tip, we transform these equations to a reference configuration
and derive the dynamic stress singularities. Furthermore, we assume
that an energy balance law is valid. Exploiting the knowledge on
the singular behaviour of the crack fields, we derive from the energy
balance law a dynamic energy release rate. Comparing this energy
release rate with an experimentally given fracture toughness we get
an ordinary differential equation for the crack tip motion. We present
first numerical simulations for a Mode I crack propagation.
Nutzer
