An explicit formulation of the Greenʹs operator for general one-dimensional structures

A general procedure for the determination of the explicit expression of the Greenʹs function of an ordinary differential operator is described in the paper, that requires only the knowledge of the null spaces of the operator and its adjoint. Although the main results concerning the structure of the Greenʹs function are known in the literature, the proposed approach is suitable for symbolic mathematics systems and has been addressed in particular for frame structures including various beam models. The general expression of all the influence functions is given and some analytical results are presented.