2 DIMENSIONAL WAVE FRONT SHAPE INDUCED IN A HOMOGENEOUSLY STRAINED ELASTIC BODY BY A POINT PERTURBING BODY FORCE

The shape of The two (spatial) dimensional wave front induced in a finitely strained elastic body by an impulsive point body force is investigated. The elastic body is characterized by three parameters which are restricted by the requirement that the governing system of equations be strictly hyperbolic. The wave front is constructed as the envelope of a one parameter family of straight lines. For different combinations of α, β and γ the wave front is shown to have zero, two or four cuspoidal triangles. The interiors of these triangles are found to be lacunas, where the associated displacements vanish identically. © 1969 Springer-Verlag.