Title:
Modeling of Strain Penetration Effects in Fiber-Based
Analysis of Reinforced Concrete StructuresConcrete Structures
Author(s):
Jian Zhao and Sri Sritharan
Publication:
Structural Journal
Volume:
104
Issue:
2
Appears on pages(s):
133-141
Keywords:
bond; column; reinforced concrete; strain; wall.
DOI:
10.14359/18525
Date:
3/1/2007
Abstract:
In flexural concrete members, strain penetration occurs along longitudinal reinforcing bars that are fully anchored into connecting concrete members, causing bar slips along a partial anchoring length and thus end rotations to the flexural members at the connection intersections. Ignoring the strain penetration in linear and nonlinear analyses of concrete structures will underestimate the deflections and member elongation, and overestimate the stiffness, hysteretic energy dissipation capacities, strains, and section curvature. Focusing on the member end rotation due to strain penetration along reinforcing bars fully anchored in footings and bridge joints, this paper introduces a hysteretic model for the reinforcing bar stress versus slip response that can be integrated into fiber-based analysis of concrete structures using a zero-length section element. The ability of the proposed hysteretic model to capture the strain penetration effects is demonstrated by simulating the measured global and local responses of two concrete columns and a bridge T-joint system. Unless the strain penetration effects are satisfactorily modeled, it is shown that the analysis of concrete structures will appreciably underestimate the local response parameters that are used to quantify structural damage.