Lateral restraining device for pressed steel structure and using method of lateral restraining device

The invention discloses a lateral restraint device for a pressed steel structure and a using method of the lateral restraint device. The lateral restraint device comprises a bottom plate. The four supporting stand columns are vertically arranged above the bottom plate and distributed in a rectangular shape. Wherein a first fixed connecting piece is arranged between two supporting stand columns, and a second fixed connecting piece is arranged between the other two supporting stand columns; the first lateral restraining assemblies are horizontally arranged between the first supporting stand column and the fourth supporting stand column. The second lateral restraining assemblies are horizontally arranged between the second supporting stand column and the third supporting stand column, and the first lateral restraining assemblies and the second lateral restraining assemblies are evenly distributed in the height direction of the supporting stand columns; the pressed test piece is vertically arranged between the fi