500MPa grade steel bar;  eccentric compression column;  Experimental studies

Through the test of the stress performance of nine 9 mm×350 mm×200 mm 2200 MPa reinforced concrete eccentric compression columns, the load-deflection curve, load-rebar strain curve, load-concrete compressive strain curve and failure morphology of eccentric compression column were analyzed. The experimental results show that the 500 MPa grade steel bar has good synergy with concrete in the column, and its strength is fully exerted. On the basis of experimental and theoretical analysis, the design value of 500 MPa grade steel bar in concrete column is proposed with the design value fy=500 MPa and the calculation formula of compressive bearing capacity.