科研之友
微信
新浪微博
Facebook
分享链接
摘要
Structural robustness reflects the insensitivity of a structure system to local damages. To evaluate the progressive collapse resistance of steel frames, a quantitative assessment method for the robustness of steel frames is presented. By considering the contributions of structural members to the structural energy distribution and the influence areas of localized damage of structural members, a method for calculating the importance indices of members is given, which can be used to determine the most possibly unfavorable initial damage modes of a frame structure. By analyzing the steel member load capacity redundancy and the strain energy sensitivities of individual members, a structural redundancy index of steel frames is brought forward based on the localized damage modes, which is directly proportional to the member load capacity redundancy and inversely proportional to the member strain energy sensitivity. The minimum of the structural redundancy indices is employed to measure the robust performance of a steel frame, after discussing the differences in definition between structural redundancy and structural robustness. A quantitative assessment approach to structural robustness of steel frames in terms of damage mode based structural redundancy is proposed, and the scope of its application is then analyzed. Finally, an example of 8-story space steel frame is given to demonstrate the feasibility of the presented approach to evaluating the structural robustness of steel frames.
