Elevation adjusting device for steel truss and method for adjusting elevation of steel truss

The invention discloses an elevation adjusting device for a steel truss and a method for adjusting the elevation of the steel truss, and belongs to the field of steel truss construction technology. The elevation adjusting device is arranged at the tops of steel pipe upright posts (6) of a steel truss temporary support, and is characterized by comprising a bottom frame (1) formed by welding two parallel H-shaped steels; an H-shaped steel, which is arranged transversally relative to the H-shaped steels of the bottom frame (1), is connected to the upper part of the bottom frame (1) through bolts; two rectification lifting jacks (2) are arranged at the upper part of the bottom frame (1) and on two sides of the upper H-shaped steel respectively. According to the elevation adjusting device and the method, the elevation and the pre-camber of the steel truss can be adjusted promptly and conveniently during the construction process of the steel truss, so as to ensure the safety and quality of the construction of the s