METHOD FOR BRIDGE RETROFITTING Russian patent published in 2001 - IPC

FIELD: bridge engineering. SUBSTANCE: method for retrofitting a bridge with span and footings involves assembly of temporary supports and cross piers with cantilevers and knurling ways, mounting new span, cross displacement of new span to axle of existing bridge, and throwing off the old span. Novelty is that relations between lengths of cantilevers of cross piers are found from equations given in description of invention and that knurling ways are installed in vicinity of cantilevers in throw-off direction at obtuse angle α, assumed to be 169.9-179.9 deg. When work is done in cold seasons, layer of reinforced fern or timber pad, or shock-absorbing ground pad may be made on ice surface around footings and between voids near throw-off area to throw off old span; parameters of all these structures are to be found from equations given in description of invention. EFFECT: improved reliability of bridge; reduced cost and labor consumption. 4 cl, 1 dwg