Seismic steel tubular column with internal local restraint and filled with high strengthen compound concrete containing normal-strength demolished concrete lumps and construction process of such column

A seismic steel tubular column with internal local restraint and filled with high strengthen compound concrete containing normal-strength demolished concrete lumps, characterized in that:

• horizontal stirrups are provided at upper and lower ends inside a steel tube, with the steel tube having a circular or polygonal section;
• the horizontal stirrups corresponding to the circular section are uniformly arranged in one-seventh of a height range at the lower end of the steel tube and in one-seventh of a height range at the upper end of the steel tube respectively, while the horizontal stirrups corresponding to the polygonal section are uniformly arranged in one-fifth of a height range at the lower end of the steel tube and in one-fifth of a height range at the upper end of the steel tube respectively;
• high-strength fresh concrete is poured and normal-strength demolished concrete lumps are put alternately inside the steel tube, with a compressive strength of the high-strength fresh concrete being 30˜90 MPa greater than that of the normal-strength demolished concrete.