Modal Analysis of Tower Crane with Cracks by the Dynamic Stiffness Method

Abstract

The dynamic stiffness method is a powerful approach that enables to obtain more exact solution in dynamic analysis of structures, especially, when high frequency vibrations need to be investigated. On the other hand, the dynamic characteristics of high frequency modes of a structure are more sensitive to local damage such as crack. Therefore, the dynamic stiffness method gets to be a most efficient approach to analysis and identification of engineering structures. This report is devoted to modal analysis of tower crane with cracks by using the dynamic stiffness method. First, dynamic stiffness model of tower crane is conducted on the base of cracked beam element where crack is treated by an equivalent spring. Then, the established model is used for modal analysis of a typical tower crane.