Title: Simplified Two-Column Analytically Based Fiber Model

Author(s): Donald J. Phillippi and Gilbert A. Hegemier

Publication: Structural Journal

Volume: 114

Issue: 2

Appears on pages(s): 349-359

Keywords: bridge; column; ductility; earthquake-resistant; flexural strength; shear strength

DOI: 10.14359/51689427

Date: 3/1/2017

Abstract:
Two-column rigid-cap beam bridge bents are often used as transverse-to-bridge lateral force-resisting systems. Seismic performance of two-column bridge bents were investigated at the University of California, San Diego, and results of quasi-static tests on two one-third-scale bridge bents that replicated the Dumbarton Bridge in the San Francisco Bay area were presented. In the previous research, a nonlinear, three-dimensional (3-D) computer program was used to determine actual shear distribution in a two-column bridge bent, proving that the column under compression was more vulnerable to shear degradation. This paper presents a new simplified, analytically based fiber model for rigid-cap beam bridge bents. Results from the model showed agreement with previous nonlinear 3-D simulations. The model also provides an assessment of force-displacement performance of piers that allows monitoring of changes in axial load and shear force distributed in each column, resulting in state of stress and/or strain of various column components.