Thickness-adjustable reusable assembly type pipe jacking construction rear backrest

The utility model discloses a thickness-adjustable reusable rear backrest for assembled pipe-jacking construction, and mainly relates to the technical field of power cable pipe-jacking construction. Comprising a plurality of connecting bolts and a plurality of steel members which are sequentially arranged from front to back, the front side face of the steel member at the foremost end abuts against a concrete structure, the front side face and the rear side face of each steel member are planes, the left end and the right end of each steel member are each provided with at least one wing plate, and mounting holes matched with the connecting bolts are formed in the wing plates. The thickness of the backrest can be adjusted by adjusting the using number of the steel members, and all the used steel members are connected into a whole through the connecting bolts; the thickness of the chair can be adjusted according to needs, the chair is convenient to disassemble and assemble and can be repeatedly used, and meanwhil