Research on Crack Estimation Method of Structure based on Pulsed Vibration Excitation Method

Abstract

Pulsed vibration excitation is a nondestructive technique that can assess the dynamic characteristics of materials (Young’s modulus, Poisson’s modulus) and the crack characteristics present in the specimen by measuring and analyzing the fundamental resonance frequency of an elastic hammer, and is constantly expanding in engineering practice. In this paper, a mathematical model is proposed to evaluate the crack characteristics present in various types of structural elements based on the excitation of pulsed vibrations with cracks. The relationship between the modal parameters and the crack characteristics is evaluated by applying the concept of modal strain energy. When a crack exists in a structure, the energy released varies with its size and location, which affects the natural vibration mode and natural vibration frequency of the structure. This effect was considered using the commercial software ABAQUS and experimentally verified using a high-temperature elastic modulus measurement device IET-1000 based on pulsed vibration excitation. The results show that the method suggested in this paper can fairly accurately identify the crack characteristics.