Prestress Optimization of Cable Domes with Plant Growth Simulation Algorithm Based on Stage Growth

In order to seek a reasonable and efficient prestress optimization method for cable domes, this paper proposed a new strategy for growth diffusion mechanism of large step and screening mechanism of growth points by analyzing the basic principle and algorithm mechanism of plant growth simulation algorithm (PGSA). On this basis, the plant growth simulation algorithm based on stage growth (stage growth PGSA) was established. This algorithm divides the optimization process into multiple stages and introduces the corresponding growth diffusion mechanism or screening mechanism of growth points in different stages. Firstly, the growth diffusion mechanism of large step was introduced to realize the spread of growth points by means of one-time diffusion growth with multiple steps. Then, the fast search was carried out with the medium step and the loose screening mechanism. Finally, the convergence was conducted with the small step for accuracy requirements and the strict screening mechanism. Thus, the prestress optimization of cable domes was done by using the stage growth PGSA and compared with other algorithms. The results show that the stage growth PGSA can effectively improve the global searching ability, reduce the growth space, and avoid growth points becoming saturated compared with the original PGSA. The number of calculation iteration of stage growth PGSA is the smallest and the initial strain energy of the structure after optimization is minimal in comparison with those of the multi-island genetic algorithm, adaptive simulated annealing algorithm, and particle swarm optimization algorithm. With its higher optimization efficiency and better optimization effect, therefore, this algorithm is applicable to the prestress optimization of cable domes.