Polyurethane expansion device for bridge

A polyurethane expansion device for a bridge aims at ensuring that the left side and the right side of an expansion body are stressed and deformed uniformly, prolonging the service life of the expansion body and the whole device and reducing the line operation and maintenance cost. The guide component is composed of a left guide pipe, a guide rod and a right guide pipe which are symmetrically arranged along the vertical center line of the beam end expansion joint. The two ends of the guide rod extend into the left guide pipe and the right guide pipe respectively and are in axial sliding fit with the left guide pipe and the right guide pipe. The anchoring component is composed of a U-shaped component and anchor rods, the U-shaped component extends along the beam end expansion joint in a full-length mode, the anchor rods arranged at intervals penetrate through the bottom of the U-shaped component and are welded to embedded steel bars extending into a concrete leveling layer from a beam body, and the outer ends