Multi-parameter monitoring for steel pipe structures using monolithic multicore fibre based on spatial-division-multiplex sensing

摘要

In recent years, great importance has been put upon the safety monitoring towards pipelines. In this paper, multi-core optical fibre and the spatial-division-multiplex sensing technique were developed and applied to monitor the working condition and health status of the steel pipes. In order to validate the feasibility of the proposed method, a scale model of the steel pipe as the test specimen was experimentally investigated, and the static and dynamic test were conducted respectively. 7-core fibre and the spatial-division-multiplex sensing techniques were employed to monitor the structural response including the deformation and vibration. With the help of the proposed multi-core fibre based recognition techniques, the ambient temperature can be accurately evaluated with the error of +/- 0.5 degrees C, and the structure vibration can be monitored with the maximum error of 3.8% compared with the results of accelerator and displacement meter. All results show that the 7-core fibre has excellent performance on detecting the structural strain and mode frequency. The accuracy and reliability of the experiment results prove that the multi-parameter hybrid measurement based on spatial multiplexing of multi-core optical fibres has wide application prospects in the structural health monitoring of underground pipelines as well as pipes in buildings and other infrastructures. (C) 2020 Elsevier Ltd. All rights reserved.