Refined finite element analysis of helical wire ropes under multi-axial dynamic loading

Due to high tensile strength, light weight, and good flexibility, the steel wire ropes with helical structures are widely used as crucial load-bearing components in various industrial sectors such as civil engineering. They are subjected to significant vibrations caused by multi-axial dynamic loading during the service period which may eventually result in premature failures. This paper presents a refined finite element analysis method for helical wire ropes under multi-axial dynamic loading. The proposed method employs multi-directional dynamic excitations extracted from the analysis of the overall engineering systems to consider actual loading conditions. Refined finite element analysis of the entire steel wire rope under multi-axial dynamic loading is carried out for the first time based on the global-local finite element model to obtain detailed mechanical responses. The critical rope segment is represented by solid elements taking into account the helical structure, inter-wire frictional contact, slippage, and material nonlinearity, among others, and non-critical segments are simulated with beam elements in the established global-local model, which can achieve good balance between computational efficiency and accuracy. The refined finite element modeling strategy is validated via three numerical examples with comparisons against the results in the literature. The proposed method is illustrated on the suspender cable used in suspension bridges. Detailed mechanical responses and their influencing factors are examined to acquire new insights into the dynamic mechanical characteristics of typical double-helical wire rope. The present work can provide an efficient tool for the assessment of in-service engineering systems containing helical wire ropes.