Dispersion characteristics of guided waves in ice layers and experimental study of parameter inversion

To efficiently and accurately determine ice thickness and mechanical parameters, the feasibility of inverting ice layer parameters using guided waves is investigated. An isotropic sea ice waveguide model is first adopted to compute the dispersion curves of leaky guided waves in the ice layer. By analyzing the acoustic propagation characteristics and parameter sensitivity of the ice waveguide, experiments are conducted both in a laboratory and in Qinghai Lake. A single-shot multi-receiver array is deployed on the ice surface to capture guided wave signals, from which dispersion curves are extracted. Theoretical and experimental results indicate that the QS, QA₀, and QS₀ modes are all sensitive to variations in ice thickness. The QS₀ mode exhibits sensitivity to changes in Young’s modulus and Poisson’s ratio, whereas the QS and QA₀ modes are insensitive to these parameters. In the laboratory, the QS₀ mode is successfully utilized to invert the Young’s modulus, Poisson’s ratio, and ice thickness, yielding values of 7.323 ± 0.154 GPa, 0.361 ± 0.01, and 39.31 ± 0.36 mm, respectively. In the field experiment, the QS mode is successfully captured and used to invert ice thickness, with an inversion error of less than 5%. This study lays the foundation for large-scale field experiments and parameter inversion of ice layers.