Jack for steel truss girder upper chord member installation and steel truss girder upper chord member installation process

The invention discloses a jack for steel truss girder upper chord member installation. The jack comprises a jack body. A connection plate is fixedly arranged on the bottom of the jack body and provided with two or more through holes matched with splice plate holes in a diagonal to be installed. A supporting part is arranged at the end of an ejection rod of the jack body. In use, the jack is installed on the steel truss diagonal in advance, the distance between rod members is set through the jack in advance, the jack carries out fine adjustment when chord members are hoisted, hole alignment is convenient, installation is easy and convenient, and the upper chord members can be installed fast. The invention further provides a steel truss girder upper chord member installation process. According to the process, the upper chord members can be installed fast, stress on the diagonal can be reduced, the weight is not increased in the installation process of the upper chord members, the high altitude operation time of workers is shortened in the installation process of the upper chord members, the risk of the workers is also lowered in the installation process of the upper chord members, and the assembly speed of the rod members is increased.