Lateral bearing capacity of self-centering prestressed concrete filled steel tubular lattice rocking tower

Prestressed concrete filled steel tubular (CFST) lattice tower innovatively combines prestressing with CFST structures for onshore wind turbine towers in low wind speed regions, where compression-bending loads constitute the predominant load during the design process. To investigate influences of prestressing on seismic performances of such novel tower structures, pseudo-static scaled experiments were conducted under compression-bending loads by varying boundary conditions at the base of prestressed CFST lattice tower. The analysis focused on several mechanical performance parameters, including failure modes, load-displacement hysteretic curves, ultimate load capacity, energy dissipation, stiffness degradation, and prestress variations, thus providing recommendations for optimizing design parameters of the tower. Subsequently, employing the validated finite element (FE) model derived from experimental results, parametric analysis was performed to evaluate effects of material strength, specimen dimensions, and prestressing on structural load-carrying capacity, thus providing recommendations for optimizing the design parameters of the tower. Drawing upon comprehensive analysis of rocking behavior for self-centering prestressed CFST lattice rocking tower subjected to compression-bending loads, alongside rigid body rocking theory, a bilinear simplified calculation model was developed for deriving lateral load-carrying capacity of such rocking structure. The rationality of the proposed theoretical calculation method was substantiated through comparisons of experimental data and FE analysis results.