Damage Assessment of High-Rise HSC Shear Structure: I—Modification of Park-Ang-Wen Damage Index for HSC and Failure Modes

The present research is focused on the damage assessment of high-rise shear structures (having short shear dominant members) made up of high-strength concrete (HSC). For this, the widely used Park-Ang-Wen (P-A-W) damage index formulation was selected. However, this index was limited to the use of normal-strength concrete, despite examining columns with flexural and shear failures based on their monotonic force-displacement diagram and not under cyclic loading. To alleviate these limitations (all failure modes, especially shear and flexural shear failure under cyclic loading), specimens were selected from the PEER database, and using non-linear regression, new relationships for ultimate displacement of members under monotonic loading (δu) and the energy correction factor (β), which both appear in the P-A-W damage index formula, were proposed. The corrected displacement relationship with C.C = 0.879 and the energy coefficient relationship with R2 = 0.7569 and C.C = 0.7414 show better results compared to the relationship of Park et al. Using these relationships, damage index values were calculated for several samples, which yielded values close to 1 at the unrepairable damage level and were approximately 36% of the values obtained from the original P-A-W relationship. Also, this value is 54% of the P-A-W formula for HSC samples and 41% of the P-A-W formula for shear-failure samples. Details of this research are covered in the present paper (I) and its application to high-rise HSC shear structure is presented in paper II.