Cable Tension Monitoring Based on the Elasto-Magnetic Effect and the Self-Induction Phenomenon.

Zhang Zhang,Zhou Zhou,Chen Chen

doi:10.3390/ma12142230

Abstract

Cable tension monitoring is important to control the structural performance variation of cable-supported structures. Based on the elasto-magnetic effect and the self-induction phenomenon, a new non-destructive evaluation method was proposed for cable tension monitoring. The method was called the elasto-magnetic induction (EMI) method. By analyzing the working mechanism of the EMI method, a set of cable tension monitoring systems was presented. The primary coil and the induction unit of the traditional elasto-magnetic (EM) sensor were simplified into a self-induction coil. A numerical analysis was conducted to prove the validity of the EMI method. Experimental verification of the steel cable specimens was conducted to validate the feasibility of the EMI method. To process the tension monitoring, data processing and tension calculation methods were proposed. The results of the experimental verification indicated that different cables of the same batch can be calibrated by one proper equation. The results of the numerical analysis and the experimental verification demonstrated that the cable tension can be monitored both at the tension-applying stage and the tension-loss stage. The proposed EMI method and the given monitoring system are feasible to monitor the cable tension with high sensitivity, fast response, and easy installation.

Highlights

Cable-supported structures are extensively applied in infrastructure construction, such as in bridges and roofs [1]
The results demonstrated that the elasto-magnetic induction (EMI) method and the given system are feasible to monitor cable tension with high sensitivity, fast response, and easy installation, apart from the advantages of the traditional EM sensor
The results demonstrated that the length of the self-induction coil has little effect on the accuracy of the cable tension monitoring

Summary

Introduction

Cable-supported structures are extensively applied in infrastructure construction, such as in bridges and roofs [1]. Steel cables are the main bearing members of the cable-supported structures group. The cables ensure the bearing capacity of the cable-supported structures [2]. The tension of the cable starts changing since the steel cable has been installed and tensed. Cable tension varies because of various factors such as the performance of the materials, the construction situation, and the external environment [3,4]. Variation of the cable tension often leads to structural performance variation of cable-supported structures [5,6]. The cable tension should be monitored accurately

Methods

Results

Conclusion