Numerical investigation on the buckling behavior of damaged steel members constrained by outer tubes

Recently, the collapse of space truss structures has been a public concern, often triggered by local damages of key components. The enhancement effects of buckling-controlled methods on the damaged members of space truss structures are systematically investigated by the detailed numerical analysis. Different local damages are introduced to the members to discuss the influence of damage positions and levels on the bearing capacity and displacement ductility. The sensitivity analysis is also performed to select representative damage modes. Compressive sleeve columns are designed and simulated for the damaged tubes, and the simulation method is verified by the reference tests. Moreover, parametric analysis is carried out to analyze the influence of the protrusion length, stiffness ratio and gap on the post-buckling behavior of members, including the failure mode, bearing capacity, enhancement effect and displacement ductility. Different designs of the outer tubes are proposed for the inner tubes with various damages. The principle in this work can effectively guide the reinforcement of the damaged members.