Hysteretic shear–flexure interaction model of reinforced concrete columns for seismic response assessment of bridges

Abstract

This paper presents the methodology, model description, and calibration as well as the application of a coupled hysteretic model to account for nonlinear shear-flexure interactive behavior of RC columns under earthquakes, a critical consideration for seismic demand evaluation of bridges. The proposed hysteretic model consists of a flexure and a shear spring coupled at element level, whose nonlinear behavior are governed by the primary curves and a set of loading/unloading rules to capture the pinching, stiffness softening, and strength deterioration of columns due to combined effects of axial load, shear force, and bending moment. The shear-flexure interaction (SFI) is considered both at section level when theoretically generating the primary curves and at element level through global and local equilibrium. The model is implemented in a displacement-based finite element framework and calibrated against a large number of column specimens from static cyclic tests to dynamic shake table tests. The numerical predictions by the proposed model show very good agreement with experimental data for both flexure-and shear-dominated columns. The application of the proposed model for seismic assessment of bridges has been successfully demonstrated for a realistic prototype bridge. The factors affecting the SFI and its significance on bridge system response are also discussed.

Seismic Response of Reinforced Concrete Columns

“…Few studies in the recent past have also addressed the issues of stiffness degradation and strength deterioration in the reinforced concrete elements dominated by shear or shearflexure behaviors. These studies represent advanced formulations for fiber-based element (Ceresa et al, 2007(Ceresa et al, , 2009Chao & Loh, 2007;Mullapudi & Ayoub, 2008, 2010Xu & Zhang, 2011;Zhang & Xu, 2010) and Macro-element model (Mergos & Kappos, 2008, 2010 and consider interaction between inelastic shear and nonlinear flexural behaviors with different conceptual backgrounds, solution strategies and implementation complexities. A state-of-art review is presented on fiber elements with focus on concentrated plastic-hinge type model that can be implemented in displacement-based finite element programs (Ceresa et al, 2007).…”

Modelling Approaches for Inelastic Behaviour of RC Walls: Multi-level Assessment and Dependability of Results

“…6.2. Several LPMs, as finite element counterparts of PHA, can obviously also account for shear deformations and flexure-shear interaction through similar or alternative assumptions [60,65,66].…”

Behavior, design, and modeling of structural walls and coupling beams — Lessons from recent laboratory tests and earthquakes

“…More Recent research has focused on accounting for interaction (or coupling) between axial-flexural and shear responses, 12-15 with various modeling approaches proposed, e.g., fiber/section based models, 7,16-18 strut models, 19 and simplified models using analytical 20 or experimental results. 21 Wall test programs focused on providing data for validation of shear-flexure interaction models for intermediate wall aspect ratios have recently been completed.…”