Thermal and integral lifting analysis of a lattice shell lighting roof based on genetic algorithm and probabilistic design

• Support stiffness of a complex steel structure was optimized by GA method.
• Influence of temperature load was minimized by optimization of support stiffness combination.
• Probability distribution model of lifting height difference was put forward.
• Probabilistic design method was adopted to analyze integral lifting of complex steel structures.

The optimum analysis for Railway Station Building of Yujiapu (a shell-shaped single-layer reticulated shell structure) was conducted based on genetic algorithm. An elitist genetic algorithm was used by combining Matlab and a general finite element software ANSYS. Analysis was firstly conducted to study the influence of temperature load on support reaction force, then the optimal combination of support stiffness to minimize the effects of temperature load was derived by using GA. Subsequently, probabilistic design analysis was conducted for the integral lifting process and the key lifting points which influence the stress of lifting zone significantly was derived, at the same time the probability distribution model of lifting height difference was established and validated. Finally, the same genetic algorithm was adopted to optimize the combination of lifting height difference, the maximum stress of lifting zone will be reduced obviously by using the computed results. The efficiency and applicability of GA in optimization of complex structures were demonstrated in this paper.