Patent ID: 6170106
Filing Date: 2001-01-09
Classification: E01D

Abstract:
In a bridge having a roadway for vehicular, railway and/or pedestrian traffic, the roadway having a usable given width for normal traffic flow, wherein maintenance, repair or construction operations are being performed on the bridge, and wherein a traffic shield is constructed within a respective longitudinal section of the bridge, thereby enabling the traffic to flow on the roadway of the bridge substantially uninterrupted while the maintenance, repair or construction operations are being performed on the respective longitudinal section of the bridge, such that the traffic on the roadway of the bridge is protected against falling debris, and, at the same time, the workers performing the maintenance, repair or construction operations are shielded from the traffic flow, and wherein when the operations on the respective longitudinal section of the bridge are completed, the traffic shield is normally dismantled and thereafter reconstructed on a next adjacent longitudinal section of the bridge, the improvement wherein the traffic shield comprises a safety tunnel which is movable along the length of the bridge, thereby eliminating the necessity for repeatedly dismantling and reconstructing the traffic shield as the maintenance, repair or construction operations on the bridge continue progressively along the length of the bridge, the safety tunnel riding on rails, and the safety tunnel being alternately locked and unlocked on the rails, wherein the safety tunnel has an interior width which is equal to or greater than the usable given width of the roadway thereby minimizing any interference with the normal traffic flow on the bridge, and wherein the roadway of the bridge has respective sides, each of which is provided with a parapet, wherein the rails are mounted on the parapets, and wherein the movable safety tunnel rides on the rails on the parapets.