To prevent the falling of a bridge by installing L-shaped brackets long in the breadth direction to the underside of a bridge body in the front of abutments for the concrete slab bridge and fixing the brackets onto the abutments by bolts buried to the abutments.

When the movable end side of a bridge body 2 is borne to bearing seats for abutments 5, the horizontal sections of L-shaped brackets 10 made of steel are clamped by unbonded prestressing steel bolts 11 vertically penetrated to the bridge body 2. Anchor bolts 13 are buried to the abutments 5, and the vertical sections of the brackets 10 are fixed in a displaceable manner through cushioning materials 12 such as a neoprene rubber and bearing plates 14. Accordingly, even when the abutments are displaced, the falling of a bridge can be prevented.