Structural Engineering Online Library

  1. Home
  2. Structural Engineering Online Library
Keller's Keller NextGen Summit begins at 01 Oct 2025
More
Create a free account and view content that fits your specific interests in structural engineering Learn More
Register

Publications on P. Mergos

A gradual spread inelasticity model for R/C beam-columns, accounting for flexure, shear and anchorage slip
P. Mergos ; A. Kappos
Book Title / Journal: Engineering Structures
Year: 2012 , Volume: 44 , Series:
Structure types ; Concrete structures
  • Description
    • A new beam-column model is developed for the seismic analysis of reinforced concrete (R/C) structures. This finite element consists of two interacting, gradual spread inelasticity sub-elements representing inelastic flexural and shear response and two rotational springs at the ends of the member to model anchorage slip effects. The flexural sub-element is able to capture gradual spread of flexural yielding in plastic hinge regions of R/C members. The shear sub-element interacts throughout the analysis with the flexural sub-element, in the location of the plastic hinge regions, in order to capture gradual spread of inelastic shear deformations as well as degradation of shear strength with curvature ductility demand based on an analytical procedure proposed herein. The skeleton curves and hysteretic behaviour in all three deformation mechanisms are determined on the basis of analytical procedures and hysteretic models found to match adequately the experimental results. Empirical formulae are proposed for the shear distortion at onset of stirrup yielding and onset of shear failure. The proposed element is implemented in the general finite element code for damage analysis of R/C structures IDARC and is validated against experimental results involving R/C column and frame specimens failing in shear subsequent to yielding in flexure. It is shown that the model can capture well the hysteretic response and predict reliably the type of failure of these specimens.
PDF
Seismic damage analysis including inelastic shear-flexure interaction
P. Mergos ; A. Kappos
Book Title / Journal: Bulletin of Earthquake Engineering
Year: 2009 , Volume: 8 , Series:
Structure types ; Concrete structures
  • Description
    • The paper focusses on seismic damage analysis of reinforced concrete (R/C) members, accounting for shear-flexure interaction in the inelastic range. A finite element of the beam-column type for the seismic analysis of R/C structures is first briefly described. The analytical model consists of two distributed flexibility sub-elements which interact throughout the analysis to simulate inelastic flexural and shear response. The finite element accounts for shear strength degradation with inelastic curvature demand, as well as coupling between inelastic flexural and shear deformations after flexural yielding. Based on this model, a seismic damage index is proposed taking into account both inelastic flexural and shear deformations, as well as their interaction. The finite element and the seismic damage index are used to analyse the response of R/C columns tested under cyclic loading and failing either in shear or in flexure. It is shown that the analytical model and damage index can predict and describe well the hysteretic response of R/C columns with different types of failure.
PDF