Title:
Effects of Displacement History on Failure of Lightly Confined Bridge Columns
Author(s):
R.T. Ranf, M.O. Eberhard, and J.F. Stanton
Publication:
Symposium Paper
Volume:
236
Issue:
Appears on pages(s):
23-42
Keywords:
bridges; columns; cycling; failure; reinforced concrete; shear
DOI:
10.14359/18206
Date:
5/1/2006
Abstract:
Six nominally identical reinforced concrete columns were subjected to a variety of lateral displacement histories to evaluate the effects of cycling on their failure displacement and failure mechanism. The columns, typical of bridges constructed before the mid-1970s, had circular cross-sections, low axial loads, and little transverse reinforcement. Shear failure caused five of the six columns to lose their axial load carrying ability at drift ratios between 3% and 5%. The sixth column failed in an axial-flexure mode at a drift ratio of 6%. Increasing the number of cycles at each displacement level from one to fifteen decreased the maximum displacement preceding flexure-shear failure by approximately 35%. The effect of cycling on damage accumulation was modeled with the Park-Ang damage model, a Modified Park-Ang damage model, and a Cumulative Plastic Deformation damage model. The Cumulative Plastic Deformation model correlated best with the observed damage, and it was the easiest to implement.