Take a sneak peek at the new NIST.gov and let us know what you think!
(Please note: some content may not be complete on the beta site.).
NIST Authors in Bold
|Author(s):||A El-Bahy; S K. Kunnath; William C. Stone; A W. Taylor;|
|Title:||Cumulative Seismic Damage of Circular Bridge Columns: Benchmark and Low-Cycle Fatigue Tests|
|Published:||July 01, 1999|
|Abstract:||An experimental study was undertaken to investigate cumulative damage in reinforced concrete circular bridge piers subjected to a series of earthquake excitations. Twelve identical quarter-scale bridge columns, designed in accordance with current AASHTO specifications, were fabricated and tested to failure. This paper summarizes the results of Phase 1 testing that consisted of benchmark tests to establish the monotonic force-deformation envelope and the energy capacity under standard cyclic loads, and constant amplitude tests to determine the low-cycle fatigue characteristics of typical flexural bridge columns. A companion paper will present the results of variable amplitude testing that focused on the effects of load path on cumulative damage. Test observations indicate two potential failure modes: low cycle fatigue of the longitudinal reinforcing bars; and confinement failure due to rupture of the confining spirals. The former failure mode is associated with relatively large displacements amplitudes in excess of 4 percent lateral drift, while the latter is associated with a larger number of smaller amplitude cycles. A fatigue life expression is developed that can be used in damage-based seismic design of circular, flexural bridge columns.|
|Citation:||Aci Structural Journal|
|Keywords:||bridges (structures), damage, reinforced concretes, piers, earthquakes, fatigue (materials), structures, cyclic loads, ductility, material properties|
|Research Areas:||Building and Fire Research|
|PDF version:||Click here to retrieve PDF version of paper (1MB)|