Numerical Simulation of Residual Behavior of Steel Concrete Interface after High Temperature Exposure

Abstract

Behaviour of reinforced concrete and prestressed concrete structures subjected to fire is an important research theme in civil engineering. In addition, experiment investigations show that the concrete behavior is strongly affected by temperature. The aim of this work is to study numerically the residual behavior of steel-concrete bond after high temperature exposure. To do a numerical study, bond stress at the steel-concrete interface were developed using a concrete damage plasticity model (CDP model) implemented in the nonlinear finite element software «ABAQUS». The physical, mechanical and damage plasticity parameters (compressive damage and tensile damage) required for the model were drawn from previous literature works and the model was validated by simulating the uniaxial compression strength test under different temperatures using Abaqus code. The model was finally applied to simulate a pull-out test made on a reinforced concrete specimen heated at various temperature (105°C, 150°C, 200°C, 300°C, 400°C and 500°C.) and then cooled at room temperature. The numerical results show a good correlation with the experimental results and clearly indicate a deterioration of bond performance when temperature increased, particularly the bond stress, bond stiffness and pull-out force. The model was also used to validate the results of initiation and propagation of cracks.

Bearing Strength of Concrete with Carbon Fibre Reinforced Plastic (CFRP) Wrapping Axially Loaded through Circular Plate

“…By taking the advantages of symmetrical geometry and loading of the concrete bearing, only a quarter size of the model is considered in this research. The contact interaction [15] for surface-to-surface (S-to-S) contact has been used to stimulate the contact interface between the steel bearing plate and the concrete surface. For vertical direction, the contact surface is based on the "hard-contact" surface.…”