桥梁主缆断丝漏磁检测系统研制

主缆作为桥梁的重要承力构件，长期服役后会出现内部钢丝断裂等问题，需要进行定期检测。为了解决桥梁主缆直径大、主缆钢丝与缠丝正交布置引起的漏磁检测难题，本文首先通过有限元仿真方法研究主缆漏磁检测的可行性，并基于仿真结果，采用模块化设计思路，研制出桥梁主缆断丝漏磁检测系统，包括驱动、传感、信号处理、WIFI通信等模块。最后开展主缆检测实验研究，实验结果表明：该系统能够检测出主缆试件表层钢丝中的3根与5根断丝缺陷，与仿真结果相符；爬行稳定且信号平稳。本研究工作将为桥梁缆索检测提供一种新手段。

Development of MFL Detection System for Broken Wire of Bridge Main Cable

As an essential load-bearing component of a bridge, problems such as internal steel wire breakage may occur in main cable after long-term operation, requiring regularly testing. To address the issues in MFL testing caused by the large diameter of the main cable and the orthogonal arrangement of the main cable steel wire and wrapping wire, the feasibility of MFL testing applied in main cable was first investigated using finite element simulation in this paper. Based on the simulation results and modular design idea, a MFL detection system for bridge main cable was developed, including the modules of drive, sensor, signal processing, WIFI communication, etc. Finally, the main cable detection experiment was carried out. The results showed that the system could identify 3 and 5 broken-wire defects in the surface-layer steel wires of the main cable specimen, which was consistent with the simulation results. And the system was able to crawl on the main cable of a bridge in service while maintaining a steady signal. This research provides a new method for the detection of bridge cables.