  This paper presents a method for generating a turbulent velocity field that
can be used as an input for the temporal simulation in wind excited structure
problems. Temporal simulations become necessary when nonlinear behaviour, in
the structure or in aeroelastic forces, must be accounted for. The main
difficulty is then to reproduce correctly the statistical properties of the
atmospheric turbulence, especially the spatial correlation. These properties
constitute here the targets that the generated signal has to satisfy. We
propose to use the biorthogonal decomposition technique which possesses
interesting features to reach this objective, notably the space-time symmetry.
Moreover, the convergence in energy is obtained rapidly with few terms of the
decomposition, particularly in the low frequency range. Thus the method is
found suitable for application to large civil engineering structures, such as
bridges. Examples are provided for two different kinds of wind.
