ABSTRACT
Over the world, there are ongoing efforts to realize the construction of submerged floating tunnels (SFTs). As part of the efforts, it is critical to continuously monitor the integrity of an SFT throughout its life span. The displacement of the SFT itself and the tension forces of the cables connecting the SFT to the ground can provide critical information regarding the condition of the SFT. In this study, a simultaneous displacement and cable force estimation technique is developed for SFTs based on acceleration and strain measurements. Strain measurements are firstly transformed into displacement using a mode superposition algorithm, and then the transformed displacement is fused with acceleration measurement using a finite impulse response (FIR) filter and a recursive least square (RLS) estimation algorithm for improved displacement estimation. Finally, the tension forces of the cables at the connection points between the SFT and the cables are estimated based on the displacement estimated at the connection points. The feasibility of the proposed technique is examined through numerical simulation and a laboratory test on an 8-m long aluminium SFT model.
