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The durability of the reinforced concrete structures highly influenced by many important factors including steel corrosion. Corrosion starts off with the availability of the water and oxygen, products formed due to this get deposited in the interface between the concrete and steel. As the depositing corrosion volume increases, an expansive pressure at the interface exerts on the surrounding concrete and eventually causes structural degradation, which reduces concrete and steel bond. This work focuses on a parametric study on rust expansion pressure to understand the effect of grade of concrete, diameter of the rebar, position of the rebar and c/d ratio using ABAQUS software. After the analysis, it is found that rust expansion pressure increases as the grade of concrete and c/d ratio increases, which means the pressure required to cause surface cracks due to corrosion is more in higher grades concrete and high c/d ratio. Position of the bar did not affect the corrosion pressure requirement to cause surface cracks. As the corrosion level increased, deflection of the beam also increased. But position of the corroded reinforcing bars in the beam slightly affects the deflection of the beam.

Present work contains a 3-D Finite Element model created in Abaqus to examine bond behavior in controlled/non-corroded Reinforced Concrete beams. Study evaluated the compatibility between corrosion levels and beam deflections. Cohesive surface-based interaction method is applied to the Data obtained from recent studies in which corrosion was induced by accelerated corrosion technique. The cohesive surface-based interaction approach has been found to be suitable for simulating the interfacial binding between reinforcement bars and the concrete. Analysis of Control and corroded beams along with mesh sensitivity are used for the validation of the work. Study demonstrated that experimental and analytical research are in good agreement with considered level of corrosion and corresponding deflections. The modelling outcomes can be used to validate the bond behaviour of Reinforced concrete cantilever beams without considering the influence of stirrups.

No abstract

The lateral-torsional buckling occurs in a beam when the beam's unsupported length is greater. The beam will fail by lateral-torsional buckling when the compression flange is free to rotate and displace laterally. The lateral stability of the I-section is an important factor in the design of pre-engineered buildings. The design to resist the bending and twisting in the frame I-section that is rafter and column in lateral direction flange bracing acts as a restraint to resist lateral-torsional buckling. The top flange is connected with purlins to act as a lateral restraint. The bottom flange torsional moment is resisted by flange bracing. Increasing the flange bracing decreases the unsupported length of the compression flange, so there is a decrease in lateral-torsional buckling. If the non-dimensional slenderness ratio ( λlt < 0.4 ) the section is said to be laterally supported, according to IS 800. In this paper, how the lateral-torsional buckling affects when the restraints are provided at different intervals and how the section will be affected when the flange width, thickness, web depth and thickness changes.