Evaluation, Calibration, and Verification of a Reinforced Concrete Beam–Column Joint Model

Abstract

A model for use in simulating the response of reinforced concrete interior beam-column joints is developed and evaluated using an extensive experimental data set. This model builds on previous work by Lowes and Altoontash in 2003, modifying the previously proposed model to improve prediction of response and extend the range of applicability. First, a new element formulation is proposed to improve simulation of joint response mechanisms. Second, a new method for simulating the shear stress-strain response of the joint core is developed. This method assumes joint shear is transferred through a confined concrete strut and simulates strength loss due to load history and joint damage following yielding of beam longitudinal steel. Third, modifications are made to enable better simulation of anchorage zone response. Comparison of simulated and observed response histories indicates that the new model represents well stiffness and strength response parameters for joints with a wide range of design parameters.

Guidelines for nonlinear structural analysis and design of buildings. part IIb - reinforced concrete moment frames

“…For joints with light transverse reinforcement, shear cracking can cause significant shear deformations even prior to yielding of the longitudinal reinforcement (Mitra and Lowes, 2007;Kim and LaFave, 2007). Test results have also shown that the stiffness of the joint depends on the relative flexural strengths of the beams and columns (Leon, 1990;Beres et al, 1992).…”

“…These approaches range from macro-elements with interface and joint panels calibrated to experimental data (Mitra and Lowes, 2007), to simpler models with rigid offsets at frame members connected by a central zero-length spring that simulate the shear and/or bar-slip behavior in joints, often referred to as scissor models (Alath and Kunnath, 1995). Jeon et al (2014) assessed the accuracy and functionality of several leading beam-column joint models and recommend joint modeling parameters and cyclic behavioral rules compatible with the scissor joint modeling approach.…”

A New Discrete Macro-Node Element for the Seismic Behaviour Modelling of Reinforced Concrete Frames

“…The basic element can be described by referring to a simple mechanical representation in which the element is regarded as an articulated quadrilateral endowed with along-side interfaces that, consistently to a fibre discretization, account for both the concrete and steel bars contributions. This macro-node possesses some similarities to the joint model proposed by Lowes and Altoontash [12], modified by Mitra, and Lowes [13] in order to simulate the behaviour of the joints without transversal steel reinforcements, afterwards calibrated and validated in [14][15][16]. However in the approach proposed herein the interfaces are discretized according to a detailed fibre discretization accounting for node and beams concrete and steel contributions.…”

“…In the following the model proposed by Paulay et al [22] and improved and experimentally validated by Mitra and Lowes [13] is considered. The joint shear behaviour is governed through an uni-dimensional constitutive law which rules the relationship between the generalised tangential stress ( ) and the generalised shear strain ( ).…”

Local bond stress-slip model for reinforced concrete joints and anchorages with moderate confinement

“…A factor contributing to crack opening is the slip of the main reinforcing bars at their anchorage and within RC joints (Brown and Jirsa 1971;Popov 1984;Limkatanyu and Spacone 2003;Lobo and Almeida 2015). This slip, which is either neglected or roughly approximated in most nonlinear analysis models, results in fixed-end rotations that lead to additional deformations and additional displacements of the structure (Filippou et al 1983(Filippou et al , 1986Saatcioglu et al 1992;Mitra and Lowes 2007;Lobo and Almeida 2015).…”