Non-Linear Strut and Tie Modelling Approach of Retrofitted Reinforced Concrete Beam Column Joint by Prestress Joint Enlargement

Articles in Press

Document Type : Original Article

Authors

• S.Ahmad Nezami ¹
• Jalil Shafaei ²

¹ Graduate MSc student, Faculty of Civil Engineering, Shahrood University of Technology, Shahrood, Iran

² Faculty of Civil engineering, Shahrood university of technology

10.22067/jfcei.2024.85341.1271

Abstract

The need to retrofitted beam-to-column joints, which are made without observing seismic details, is definitely a live and important issue. Connection damage is reported as one of the most worrying causes of building chain collapse in effective earthquakes. The absence of transverse reinforcement and insufficient bond length of the beam bottom bars in the joint area are still existing seismic weaknesses, which are still the subject of investigation and presentation of a corresponding improvement plan. The strut and tie method based on the knowledge based on the finite element method is a powerful and developable tool in the nonlinear field. In this research, analytical models are presented for the evaluation of reinforced concrete side beam-column joints with seismic, non-seismic and strengthened details based on the method of joint enlargement based on the strut and tie methods. The results of the nonlinear modeling of the strut and tie of retrofitted and un-retrofitted specimen show that this model has the ability to detect the effect of shear reinforcement of the joint area on the shear capacity and activated nonlinear mechanisms, including partial and total slip of the longitudinal beam reinforcements in the joint. Also, the influence of the dimensions of the enlargement of the joint in the design of rehabilitation and deterioration of stiffness and resistance is one of the other capabilities of the proposed equivalent truss-type model.

Keywords

• Beam-Column Joints
• Reinforced Concrete Structures
• Strut and Tie Method
• Joint Enlargement
• Equivalent Non-Linear Truss

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