The reasonable damage evaluation method for tunnel structure can be used to determine the overall safety state of the tunnel structure and can help to establish the maintenance plan of the tunnel structure. As a fuzzy system, the evaluation process of tunnel damage has the characteristics of randomness and fuzziness. Traditional tunnel damage evaluation methodologies do not account for the fuzziness and randomness of the system. Therefore, this study puts forward a visual evaluation method based on cloud theory for evaluating tunnel damage. Damage evaluation for a shield tunnel section of Changsha Metro Line Two in China has been taken as a case study. This method effectively considers the fuzziness and randomness of the evaluation system, improves robustness of the results of the structural damage evaluation, and is a simple and visual method.

In this paper, a 2D poro-elastoplastic model for wave-induced dynamic response in an anisotropic seabed is derived analytically. The seabed is treated as a porous medium and characterized by Biot’s consolidation equations. The soil plasticity and wave non-linearity are included in the model and both the pore fluid and the soil skeleton are assumed to be compressible. The nonlinear ocean waves are respectively considered as progressive and standing waves. The previous experimental data is used to validate the proposed model. Numerical results demonstrate that the influence of nonlinear wave components should not be ignored without committing substantial error. A significant difference between progressive and standing waves is also observed for the development of residual pore pressure, as well as the distribution of liquefied zone. A detailed parametric investigation reveals that the nonlinear wave-induced seabed response is also affected significantly by cross-anisotropic soil parameters.