Ground settlement monitoring method based on distributed optical fiber sensing technology

Abstract

Continuous and distributed monitoring of ground settlement is of great significance for the evaluation of ground stability. To realize the distributed on-line and real-time monitoring of ground settlement, a ground settlement strain-displacement transformation algorithm based on distributed strain data was proposed in this work. The distributed strain data was obtained by distributed optical fiber sensing (DOFS) technology. The effectiveness of the algorithm was first verified by numerical simulation, and the factors affecting the accuracy of the algorithm were analyzed. Then, experiments were carried out to verify the effectiveness of the algorithm for actual settlement monitoring. Test results show that the ground settlement displacement obtained by the proposed algorithm is basically consistent with the actual ground settlement displacement, which can meet the needs of ground settlement monitoring. However, there are still errors in the results obtained by the algorithm, which mainly come from, strain monitoring accuracy, and spatial resolution of the demodulator (k value). The smaller the k value, the higher the strain accuracy, the higher the accuracy of the algorithm.