Structural vulnerability analysis based on plastic limit state

Abstract:

To reveal the weakness of structural system by studying structural performance susceptibility to local damage,a method of structural vulnerability analysis based on the plastic limit theory is proposed,and based on the mechanism generation method,the ultimate loading factor and the corresponding failure mode of a truss structural system are analyzed.The ultimate loading factor is then used to measure the performance of the structural system.By contrasting different damage scenarios under specified structural performance requirement,the most vulnerable damage scenario can be obtained according to the variation of ultimate loading factor to the severity of damage.The results of the case study show that the structural performance degenerates with the damage severity,and the dominative failure mode also changes with the damage severity due to the variation of structural topology composition and the redistribution of structural internal force.All the components related to a certain failure mode are the key components which serve as the most influential part to the structural performance.Therefore the analytical results can be as a reference for the structural design,monitoring and maintenance.