Abstract
According to the stress characteristics of truss structure with steel as the chemical composition and the unit modal strain change before and after the damage, the square difference of the unit modal strain is taken as the damage identification indicator of the truss structure with steel as the chemical composition, and the damage level of the steel truss structure is determined by the square difference of the unit modal strain. The numerical simulation results show that, for truss with steel as its chemical composition, under the condition of complete low-order modal test, targeting on different damage conditions of single damage, multiple damage, minor damage and severe damage, this method can effectively identify the location of the damage on the structure, and determine the damage level of the steel truss structure according to the modal strain square difference of the damage units. It also has strong robustness under certain noise level, and is suitable for damage identification and location of truss with steel as the chemical composition under actual observation conditions.
