Identification of Stiffness and Damping Coefficients of Beams Supports

Supports and joints play a basic and important role in the engineering structures. It is necessary to identify the various parameters of supports. The stiffness and damping parameters are the most important parameters of a support. In this paper, an inverse method based on dynamic acceleration measurement data is used to identify and study the stiffness and damping coefficients of the supports of cantilever and doubly clamped beams. To this end, an optimization problem using the least squares method is defined, and solved subsequently. In the cantilever beam, the effect of various parameters such as the magnitude of measurement errors, number of measured data, number of sensors, time duration of the applied load, magnitudes of the stiffness and damping parameters, and time interval of data collection, on the inverse solutions are studied. For the doubly clamped beam, the effects of the magnitude of measurement errors, number of measured data, data type and number of sensors on the results are studied. The results show that the doubly clamped beam problem is much more difficult than the cantilever beam problem. It is very appropriate to use two sensors for problems with the doubly clamped beam. By careful investigation of obtained numerical results, an attempt has been made to answer the questions and difficulties that may occur during practical tests.