Development of Optic-Electric Hybrid Sensors for the Real-Time Intelligent Monitoring of Subway Tunnels

The settlement and deformation monitoring of subway tunnels had difficult in long-distance and real time measurement. This study proposed an optic-electric hybrid sensor based on infrared laser ranging technology and cable-sensing technology. The working principle, hardware layer, design details, laboratory calibration and field validation were presented and discussed. The optic-electric hybrid sensor implemented the real-time intelligent analysis modulus for the whole system which could analysis the measurement errors and improve the accuracy. The laboratory calibration tests were carried out and the results shown that the hybrid sensors had measurement resolution of 1 mm with the maximum measurement range of 100 m. A remote real-time intelligent monitoring system is established based on the hybrid sensors. The system contains an edge computing module, real-time communication module and warning light signal with three colors. The stability of data acquisition and transmission of the intelligent control monitoring system under long-term conditions was examined. Test results shown that the system was quite stable for the long-term measurement. The whole system was verified in a constructing subway tunnel of Wuhan Metro Line 8, China. According to the field monitoring results, the deformations and the state of health safety of the tunnel was evaluated. The results of this study could provide useful guidance for tunnel deformation monitoring and has great practical value in civil engineering.

[1]  Construction solid waste landfills: risk assessment and monitoring by fibre optic sensing technique , 2020, Geomatics, Natural Hazards and Risk.

[2]  Dong-Sheng Xu,et al.  Interpretation of coarse effect in simple shear behavior of binary sand-gravel mixture by DEM with authentic particle shape , 2019, Construction and Building Materials.

[3]  Huabei Liu,et al.  Macro and micro investigation of gravel content on simple shear behavior of sand-gravel mixture , 2019, Construction and Building Materials.

[5]  Pan Guorong Sources of Errors and Deformation Analysis of Laser Scanning Based Tunnel Deformation Monitoring , 2013 .

[6]  Dong-Sheng Xu,et al.  Development of a Novel Settlement Monitoring System Using Fiber-Optic Liquid-Level Transducers With Automatic Temperature Compensation , 2018, IEEE Transactions on Instrumentation and Measurement.

[7]  P. Cui,et al.  Monitoring and warning of landslides and debris flows using an optical fiber sensor technology , 2011 .

[8]  Chunyi Cui,et al.  An Ontology Framework for Pile Integrity Evaluation Based on Analytical Methodology , 2020, IEEE Access.

[9]  Francesc Pozo,et al.  A Frequency-Based Approach for the Detection and Classification of Structural Changes Using t-SNE † , 2019, Sensors.

[11]  Chunyi Cui,et al.  Performance study of energy piles in different climatic conditions by using multi-sensor technologies , 2020 .

[12]  H. Pei,et al.  Rate of capillary rise in quartz nanochannels considering the dynamic contact angle by using molecular dynamics , 2020 .

[13]  Dong-Sheng Xu,et al.  A New Measurement Approach for Small Deformations of Soil Specimens Using Fiber Bragg Grating Sensors , 2017, Sensors.

[14]  M. Huang,et al.  One-Dimensional Compression Behavior of Calcareous Sand and Marine Clay Mixtures , 2020, International Journal of Geomechanics.

[15]  Dong-Sheng Xu,et al.  Analysis of excavation induced stress distributions of GFRP anchors in a soil slope using distributed fiber optic sensors , 2016 .

[16]  H. Pei,et al.  Experimental study on a new FBG-based and Terfenol-D inclinometer for slope displacement monitoring , 2020 .

[17]  Behzad Fatahi,et al.  Field experiments on laterally loaded piles for an offshore wind farm , 2020 .

[18]  Dong-Sheng Xu,et al.  Early-Warning System With Quasi-Distributed Fiber Optic Sensor Networks and Cloud Computing for Soil Slopes , 2017, IEEE Access.

[19]  Francesc Pozo,et al.  Damage Identification in Structural Health Monitoring: A Brief Review from its Implementation to the Use of Data-Driven Applications , 2020, Sensors.

[20]  Jianhua Yin,et al.  A new measurement approach for deflection monitoring of large-scale bored piles using distributed fiber sensing technology , 2018 .

[21]  Francesc Pozo,et al.  Structural Health Monitoring for Jacket-Type Offshore Wind Turbines: Experimental Proof of Concept , 2020, Sensors.

[22]  Huabei Liu,et al.  Cyclic and postcyclic simple shear behavior of binary sand-gravel mixtures with various gravel contents , 2019, Soil Dynamics and Earthquake Engineering.