Design and Analysis of the Double Layer Spoke Cable Net Structure of the Shunde Desheng Sports Center Training Hall

The Shunde Desheng Sports Center Training Center is the largest elliptical closed double layered spoke cable network structure built in the South China region. The structure of the training center consists of vertical V-braces, external compression rings, internal tension rings, support rods, radial stress cables, and circumferential stability cables. The plane is elliptical, with a plane size of 97 m × 83 m, with the length of the long and short axes of the cable mesh being 89 m×75 m respectively, the height of the middle pressure ring is 8.3 meters. In response to the drawbacks of the complex force finding program and difficult optimization of the spoke type double-layer cable network structure system, this paper applies the improved particle swarm optimization algorithm for the first time to the above problems. Particle Swarm Optimization (PSO) is a biomimetic optimization algorithm inspired by the natural biological phenomenon of birds foraging. Although it has emerged in various optimization fields, its application in the field of large-span prestressed structures is relatively limited. Given the above situation, based on the advantages and disadvantages of PSO optimization algorithm, an improved PSO algorithm is proposed. The improved algorithm avoids the disadvantage of the original method’s inertia coefficient w not being able to be updated according to the optimization process, which leads to low optimization efficiency in the later stage of the algorithm, significantly improving the optimization efficiency of the algorithm. An improved PSO algorithm program was developed using the programming software Matlab. Through the collaborative working mechanism between Matlab and ANSYS finite element software, the improved PSO was applied to the prestressed optimization of the double-layer spoke cable network structure system. The results showed that the optimized algorithm resulted in a maximum vertical displacement of only 33 mm in the prestressed state of the double-layer cable network structure, and the optimization effect was significant, meeting the regulatory requirements of GB 50017-2017 Steel Structure Design Standard. On the basis of the above optimization, conventional elastic analysis was further carried out on the double-layer spoke cable network structure, such as modal analysis, cable network deformation analysis, cable internal force analysis, nonlinear buckling analysis, and stress ratio verification. The results showed that all indicators met the requirements of the specifications (such as the GB 50017-2017 Steel Structure Design Standards, etc.). Through the analysis of broken cables and broken ring beams, it was verified that the structure still has sufficient safety reserves in extreme situations, and that the structure has sufficient safety redundancy to ensure safety. Using finite element software, a 1∶1 actual simulation modeling analysis was conducted on the cable clamp node, and the designed envelope cable force was applied to the calculation model, verifying that the cable clamp force met the design requirements.The prestressed optimization results of the double-layer cable system structure obtained by the improved PSO algorithm meet the initial strength and stiffness requirements of the structure. Based on this, modal analysis, cable mesh deformation analysis, cable internal force analysis,nonlinear buckling analysis, stress ratio verification, cable and ring beam analysis are carried out to verify that the structure has sufficient safety redundancy. Therefore, the improved PSO provides an effective solution for the prestressed optimization problem of the cable network structure system, which can be used for solving similar problems in the future.