Load-carrying Properties Analysis Of Triangular Cross-section Composite Truss Of Long And Narrow Configuration

The airship structure is the carrier of the other subsystems of the airship, which determines the load-carrying capacity of the airship. So the airship structure design and analysis is particularly important. Mastering typical airship internal truss structure load-carrying properties laid an important foundation for the reliable application of the airship.Truss structures are commonly used and have various kinds. Combining with the skeleton structure requirements of the airship and the craft and technology application situation in domestic and foreign field, this paper designed a long and narrow configuration composite truss of triangular cross-section which is suitable for airship taking account the material selection, spatial configuration, geometry dimension, and the production process.Boundary conditions and the three load mode of bending, torsion, axial compression during the truss analysis are confirmed by the force forms and characteristics of the airship structure. The capacity and failure mode under those load modes are analyzed by geometrically nonlinear static calculation. To take full advantage of the orthotropic characteristic of composite material, improve the material utilization efficiency, and meet the extreme demands of airship for a lightweight structural, parametric sensitivity analysis should be done to discuss how the different angle of fiber twisting and different thick of web member or chord can infect the truss performance for bending, torsion, axial compression. And it can be based for parameters optimizing of the truss.In addition, in order to improve the computational efficiency of the airship skeleton structure, an equivalent truss analysis model without joint is also considered. By comparing to calculation result of the basic truss analysis model, we find the equivalent truss analysis model can achieve the same numerical simulation accuracy as the complete model.To support the conclusion of the static analysis from the perspective of truss stability, as well as to get a more comprehensive understanding of the truss load-carrying properties, this paper made an eigenvalue buckling analysis for the three kinds of load modes, namely, bending, torsion, axial compression. During stability analysis, filament winding angle, thickness of chords and web members change as the same with that in static analysis. Truss stability analysis results show that, from the trusses stability point of view, the truss static analysis results are reasonable.Aimed to verify the correctness of the numerical simulation method used in this paper, we conducted a truss bending experiment. The experimental results show that the calculated truss load-carrying properties by the used numerical simulation method is credible.