Experimental Study On Compressive Behavior Of Locally Corroded Reinforced Concrete Columns

Steel corrosion is the most important factor in the deterioration of concrete structures.In actual engineering structures,corrosion often occurs in local areas of structural members.Based on two kinds of energized corrosion methods,this paper conducts an experimental study on locally corroded reinforced concrete specimens.The main contents and results are as follows:(1)The corrosion tests of two different corrosion modes were carried out,The experiment shows:Rust expansion cracks are found in all corrosion areas,In the first corrosion mode,the rust expansion crack in the direction of III hoop is not obvious,Under the second corrosion mode,the corrosion product is produced for a long time and the width of rust expansion crack in the longitudinal direction of corrosion area is uneven.(2)The data acquisition of corrosion rate and rust expansion crack under the first corrosion mode is carried out.Numerical Analysis with MATLAB Software,The experiment shows:There is a linear relationship between corrosion rate of steel bar and rust expansion crack under different thickness of protective layer:?(28)0.03524?1.016~c?1.528~?.It lays a theoretical foundation for judging the corrosion degree of steel bar by cracking in engineering.(3)The tensile test of corroded steel bar is carried out,The experiment shows:When the average corrosion rate of steel bar is about 5%,As the thickness of the protective layer increases,the bearing capacity has been improved,When the thickness of the protective layer increases from 10mm to 20mm,more increase in bearing capacity.When the thickness of protective layer increases from 20mm to 30mm,the bearing capacity increases less.(4)Analysis of Load Displacement Curve of Corroded Specimens,The experiment shows:When the thickness of the protective layer is the same,The initial stage of the load-displacement curve of the first type of rust test piece decreases with the increase of the average corrosion rate;When the protective layer has a thickness of 20 mm,The slope of the initial stage of the load-displacement curve of the second type of corrosion test piece increases with the increase of the average corrosion rate.