Identification of Passive Devices for Vibration Control by Evolutionary Algorithms

Passive devices for vibration control (i.e., dampers and isolators) are widely adopted in many areas of engineering. For instance, such devices now provide reliable and affordable solutions in the seismic protection of industrial machines, technical equipment, buildings, and bridges. Their main advantages are simplicity and limited costs if compared to other strategies of vibration control, which also explains why the use of passive devices is becoming so popular in many civil engineering applications. The design of earthquake-resistant structures requires the assessment of the protection system’s performance by assuming specific mathematical laws for the adopted devices. These, in turn, depend on the mechanical parameters that have to be tuned properly. As a consequence, a reliable parametric identification of passive devices for vibration control is a critical point in the design process. In this chapter, a procedure is described for the dynamic identification of passive control devices through laboratory tests and evolutionary algorithms. The methodology consists of first, using standardized experimental tests, where a predefined loading condition is imposed by an external actuator; second, using soft computing numerical techniques to identify the mechanical parameters of the candidate mathematical law by minimizing the difference between the time histories of the experimental and analytical dynamic loads. The proposed procedure can be applied to a wide range of models because of its inherent stability and low computational cost and allows comparing different mechanical laws by ranking their agreement with experimental data. Final results demonstrate the effectiveness of the proposed strategy.