Preliminary Studies On Methods Of Instability Monitoring For Steel Structures

In order to prevent steel structures from failure due to instability either under normal loadings or under natural or human-caused catastrophes, most engineers used to adopt passive prevention strategies, which, to a certain degree, constrained the spans and heights of steel structures and affected their liability and economic efficiencies as well. The paper first studied the indications of impending structure instability, and then explored the methods of monitoring and forecasting of steel structure instability. It provided guidance on using more aggressive, active strategies to prevent steel structure instability.First of all, the paper reviewed the relationships between the structural instability and the changes of the stiffness, deformation, and frequency of a structure or component, which revealed the indication characteristics manifested before the instability. Secondly, the paper proposed two simplified analysis models of the constitutive relation between the axial stress and strain of the double-tube components , and applied them in space steel structures for the instability monitoring and instability forecasting .Thirdly, the paper introduced the methods of structure heath monitoring and damage diagnostics into the field of steel structure instability monitoring and investigated the steel structure instability vibration monitoring methods from the perspectives of applying GPS (Global Position System) and remote-sensing into the steel structure instability vibration monitoring, respectively. Finally, the paper conducted conceptual designs of other instability monitoring components, and preliminary research on integration of monitoring and control of the steel structure instability using instability monitoring components.