Étude de l'influence des impédances de fondation sur le comportement dynamique des lignes de transport d'énergie électrique
The great risk associated with some structures subjected to earthquakes has created the need of rigorous dynamic analysis that takes into account soil-structure interaction. A key step of this analysis consists of estimating the dynamic response of the foundations by calculating their impedance functions (i.e. dynamic stiffness K and dashpots C). Of course, one must starts by distinguishing the various types of pylons and foundations. This report consists of three different parts. Firstly, all aspects of the considered problem are exposed. Also, an original bibliographical study about the state of knowledge on the soil-structure interaction is presented; particularly calculation of the impedance functions while explaining the various concepts treated in this work. Secondly, the used code and some theoretical concepts of modeling are indicated. This part contains essentially numerical validation and some applications in order to evaluate the displacement functions of strip footings. Three typical cases are considered. For each case, the adopted mechanical characteristics correspond to a type of soil.The development of these applications allows studying the effect of the variation of the shear velocity versus the depth on the values of the real and imaginary parts of the displacement functions. Finally, impedances are applied to a tower under a transient wind loading to study their effect on the dynamic response of the structure and consequently on the behaviour of the transmission lines.
- Génie – Mémoires