Hot-rolled I-shaped steel buckling-restrained brace with simple structure

The invention discloses a hot-rolled I-shaped steel buckling-restrained brace with a simple structure, which is characterized in that hot-rolled I-shaped steel with low yield strength and high ductility is used as an inner core rod piece to bear an axial force effect, and an outer sleeve square steel pipe does not bear the axial force effect and is only used for restraining the bending deformation of the inner core I-shaped steel; restraining plates are symmetrically welded to the two sides of a web of the core I-shaped steel, and bending deformation of the core I-shaped steel around a minor axis can be restrained by abutting against the square steel pipe of the outer sleeve through the restraining plates. The distance between the constraint plates is calculated and set according to the fact that the Euler critical stress of a pressed rod piece is larger than two times of the yield strength of steel, and it can be ensured that the hot-rolled I-shaped steel buckling-restrained brace has the good energy dissipa