Seismic damage performance levels for concrete encased steel columns using acoustic emission tests and finite element analysis

摘要

Concrete encased steel (CES) columns under low-cyclic lateral loading and high axial compressive ratios were tested using the acoustic emission (AE) monitoring technique to determine their damage performance states. These damage performance states include cover concrete cracking, compressive longitudinal reinforcement yielding, cover concrete crushing or steel flange local buckling, cover concrete spalling, longitudinal reinforcement buckling, and core concrete crushing. Using the test results, a fiber finite element method was calibrated and used to numerically simulate 486 CES columns under lateral loading and determine an empirical expression for the material parameter of the Park-Ang damage model. Use of this modified Park-Ang model in conjunction with the response databank coming from the numerical analysis of the 486 CES columns, finally leads to limit damage values for the damage states of no-damage, minor-damage, medium-damage, serious-damage, and collapse.