- 【标题】Two-stage damage diagnosis approach for steel braced space frame structures
- 【摘要】In order to diagnose the location and extent of damage in steel braced space frame structures, a
two-stage damage diagnosis approach is proposed. This approach is comprised of the damage locating
vectors method and eigensensitivity analysis. By deriving formulas used to calculate characterizing
stresses in space frame members, and by defining characterizing stresses in connections, the damage
locating vectors method is extended to locate damage in space frame members and connections. In
addition, the simplified calculation of modal mass-normalization constants for damaged structures is
improved. The first- and second-order sensitivities of the modal parameter discrepancies with respect to
the structural model parameters and the stiffness matrix of beam elements with one damaged end are
utilized. To verify the effectiveness of the proposed approach, numerical simulation analysis and
experimental testing of a steel braced space frame model are performed. Ten and seven damage patterns
are simulated in the numerical example and experimental testing, respectively. Modal parameters of the
undamaged and damaged structures are extracted from the acceleration data using the natural excitation
technique (NExT) and the eigensystem realization algorithm (ERA). The extended damage locating vectors
method is utilized to determine potentially damaged elements. Based on the identified modal information,
the extent of damage of the potentially damaged elements is estimated using the second-order
eigensensitivity analysis. It is demonstrated that the two-stage damage diagnosis approach is effective
when the damage of the members or connections in steel braced space frame structures reaches a certain
level.
- 【关键词】Damage diagnosis; Damage locating vectors; Second-order eigensensitivity analysis; Steel braced
space frame; Experiment
- 【索引】SCI: 244XB, EI: 074710933522, Citation: 2
- 【获取全文】