Strengthening and Retrofitting of Damage and Corrosion Concrete Columns with CFRP Composites

High compressive strength, high performance and suitable combination with reinforcements are efficient factors in application of concrete. But stability and durability is important problem in concrete projects that must has been attended. Nowadays, retrofit and strengthening of structures has been greatly concerned by the civil and structural engineers. A new class of retrofitting methods has been developed using the versatile chemical products like as polymers, resins and reinforcement fibers. Because of several parameters, a structure sometimes needs to retrofit and improve. These structures have been retrofitted with concrete and steel jackets. But these methods have many difficult and limitation of construction. One of the new methods for retrofitting and strengthening of structures is application of advanced fiber reinforced polymer composites. The behavior and performance of these columns were analyze and evaluated in this study. A finite element analysis using ANSYS is utilized to conduct a parametric study. Effects of repairing concrete cover and the CFRP wrapping on the performance of column are investigated. Concrete column has been modeled in 4 states: Before corrosion, after corrosion, after repair and after wrapping with FRP. The wrapping of CFRP applied fully over the cylindrical columns height. It is shown that ductility and strength of columns submitted to axial load after corrosion of reinforcing bars, and spalling of concrete cover significantly decreases, whereas after repairing the concrete cover, strength is not compensated. Results show that applying CFRP wraps significantly compensate ductility and strength reduction of original column.

Keywords:

Concrete , Corrosion , Retrofit , CFRP , Finite Element Method