A NEW DISCRETE MACRO-NODE ELEMENT FOR THE SEISMIC BEHAVIOUR MODELLING OF REINFORCED CONCRETE FRAMES

Abstract. Recent earthquakes have demonstrated that the seismic behaviour of existing reinforced concrete buildings, not designed to resist to earthquake loadings, is strongly affected by the local collapses of the beam-to-column joints that can be subjected to shear collapse of the central region or bond-slip of the longitudinal steel bars. In this paper a new macro-node element able to account for the nonlinear behaviour of the beam-to-column joints is presented. The model can be represented by a simple mechanical scheme constituted by an articulated quadrilateral whose rigid edges connect beams and columns through nonlinear discrete interfaces and whose internal deformability is related to a single degree of freedom only. The model is able to account for the shear failure of the joint region as well as the flexural and shear plastic deformations at the contact edges of the connected elements allowing the nonlinear modeling of a frame structure through an assemblage of non-linear macro-nodes connected by means of elastic frame elements.

[1]  R. Park,et al.  Flexural Members with Confined Concrete , 1971 .

[2]  F. Filippou,et al.  Mixed formulation of nonlinear beam finite element , 1996 .

[3]  Bartolomeo Pantò,et al.  A Simplified Model for the Evaluation of the Seismic Behaviour of Masonry Buildings , 2005 .

[4]  J. Stanton,et al.  SEISMIC PERFORMANCE OF OLDER BEAM-COLUMN JOINTS , 2002 .

[5]  Bartolomeo Pantò,et al.  Non-linear modeling of masonry churches through a discrete macro-element approach , 2017 .

[6]  L. Lowes,et al.  Modeling Reinforced-Concrete Beam-Column Joints Subjected to Cyclic Loading , 2003 .

[7]  Rosario Gigliotti,et al.  Modified Steel Bar Model Incorporating Bond-Slip for Seismic Assessment of Concrete Structures , 2012 .

[8]  Laura N. Lowes,et al.  Evaluation, calibration, and verification of a reinforced concrete beam-column joint model , 2007 .

[9]  F. Cannizzaro,et al.  3D macro-element modelling approach for seismic assessment of historical masonry churches , 2016, Adv. Eng. Softw..

[10]  S. Kunnath,et al.  Modeling Inelastic Shear Deformation in RC Beam-Column Joints , 1995 .

[11]  John F. Stanton,et al.  A cyclic shear stress-strain model for joints without transverse reinforcement , 2008 .

[12]  James Michael LaFave,et al.  Seismic performance of reinforced concrete eccentric beam-column connections with floor slabs , 2004 .

[13]  A. Ghobarah,et al.  Modelling of shear deformation and bond slip in reinforced concrete joints , 1999 .

[14]  John B. Shoven,et al.  I , Edinburgh Medical and Surgical Journal.

[15]  K. Mosalam,et al.  Analytical Model for Predicting Shear Strength of Unreinforced Exterior Beam-Column Joints , 2012 .

[16]  Bartolomeo Pantò,et al.  A macro-element modelling approach of Infilled Frame Structures , 2014 .

[17]  Thomas Paulay,et al.  Reinforced Concrete Beam-Column Joints Under Seismic Actions , 1978 .

[18]  Paulo B. Lourenço,et al.  Seismic safety evaluation of reinforced concrete masonry infilled frames using macro modelling approach , 2017, Bulletin of Earthquake Engineering.

[19]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[20]  Amr S. Elnashai,et al.  Advanced Nonlinear Formulation for Reinforced Concrete Beam-Columns , 1994 .

[21]  Bartolomeo Pantò,et al.  A smart displacement based (SDB) beam element with distributed plasticity , 2017 .