EXPERIMENTAL STUDY ON DETECTING BROKEN WIRES IN STAY CABLES BASED ON MAGNETOSTRICTIVE EFFECT

摘要

In this paper,a sensor based on magnetostrictive effect and a set of nondestructive detection system for broken wires in stay cables have been developed aimed at solving problems such as broken wires in stay cables or defects hard to detect in cable-stayed bridge. The magnetostrictive sensor technique consists of stimulus sensor,receiving sensor and operates in pulse-echo mode. Three axisymmetric geometrical arrangement of the device is designed for the generation of longitudinal guided waves and detection echoes from defects such as cracks or corroded areas. Experimental results show that after the software filter,the maximum amplitude of a received guided wave signal could be obtained. Except for damage 1,It can be clearly recognized the response of other damage levels,which were made in a 7-m long stay cable. Finally,the potential capabilities of the magnetostrictive sensor are discussed and further research and development fields on stay cables are recommended.