Abstract: In order to increase the accuracy and reliability of the safety assessment results of quayside container crane metal structure, an evaluation index system and evaluation criteria were established for metal structure of quayside container crane. Subjective and objective weights of the indexes were determined by analytic hierarchy process (AHP) and entropy methods. An improved CWGT method (ICWGT) was worked out, and the combination weights were integrated by the ICWGT. On the basis of an improved VFS (IVFS), an ICWGT-IVFS multi-level evaluation model was built. A practical example was given to verify the effectiveness of the model. The results show that ICWGT can overcome the drawback of negative weight coefficient, and that the ICWGT-IVFS model can avoid the inconsistencies between indicator standard and system criterion of quayside container crane metal structure, which is helpful in improving the accuracy of metal structure safety evaluation of quayside container crane.

Key words: quayside container crane, metal structure, improved variable fuzzy sets (IVFS), safety assessment, combination weights, improved combination weighting model of game theory (ICWGT)