Abstract: The stiffness of a griddle body was enhanced using dynamic topological optimization under multiple frequencies constraints. In order to avoid the tedium solution of mapping and ill loading cases, the element (or element group) sensitivity of eigenvalue was presented. The nondimensional measure used for identification of the element (or element group) under multiple frequencies constraints to be changed is given. The optimal procedure is described. In the optimal process, available stiffeners were added to the structure as to form the base structure, and the added elements are divided into groups base on the stiffeners. The present procedure was implemented for the griddle body, and effective results were obtained.

Key words: solidstate mechanics, multiple frequencies constraints, topological optimization, element sensitivity of eigenvalue