Counter-force pre-pressing system and pre-pressing method for ultrahigh cantilever beam 0 # block support

The invention belongs to the technical field of bridge construction safety and in particular relates to a counter-force pre-pressing system and pre-pressing method for an ultrahigh cantilever beam 0 #block support. The system comprises steel pipe supports erected on bearing platforms on the two sides of a pier column. A bottom template is arranged at the tops of the steel pipe supports and the pier column; the upper end of the bottom template is provided with a plurality of distribution beams which are uniformly arranged along the transverse full length of the bridge; each distribution beam is provided with three groups of jacks which are uniformly arranged along the length direction of the bridge; the top of each jack is provided with a bailey truss arranged in the transverse direction of the bridge in a full-length mode. A plurality of finish rolling deformed steel bars are pre-buried in the top of each pier column, the finish rolling deformed steel bars penetrate through the baileytrusses and limit the bai