Efficient analysis and evaluation method for overall lifting of large-span spatial grid structures

Abstract

Large-span spatial grid structures are commonly employed on the roofs of various public buildings and are typically installed via an overall lifting method. However, the process of overall lifting cannot ensure complete synchronization, which may result in damage to the structure or the lifting equipment. It is imperative to ascertain the limit state of the structure under asynchronous conditions and to develop an accurate model for rapidly assessing the critical response during the lifting process. This paper introduces an efficient approach for evaluating and analyzing the overall lifting process of large-span spatial grid structures. The iterative limit boundary (ILB) method is proposed in this paper, which facilitates the rapid determination of the limit boundary and the limit state for a structure-equipment system with asynchronous lifting. Furthermore, the genetic algorithm is integrated into the ILB method to enhance its efficiency when dealing with numerous lifting points. An agent model capable of outputting key structural responses is developed for the rapid evaluation of those responses throughout the lifting process. Both a numerical example and an engineering example are provided to validate the proposed method. The computational results indicate that the method proposed achieves accurate results with a computational cost merely 3 % of that of the Monte Carlo simulation. Additionally, the agent model established within the limit boundary, operates at a speed 200 times faster than finite element analysis, thereby enabling precise and real-time critical response assessments.