The Barnhart team was contracted for the removal of a bridge in Connecticut, but the presence of power lines above and below bridge complicated its removal.
Barnhart relied on a pull-up gantry and a slide.
The Barnhart team was contracted for the removal of the Hales Road Bridge over Metro-North Railroad in Westport, CT. The bridge was estimated to weigh 93k and measured 60'L x 25'W. The project was complicated by the presence of power lines both above and below the bridge, so the standard means of removal were eliminated.
A 135' span of 5 ft girder was assembled to remove the bridge. The girder configuration could not be set with a crane alone, instead the full length girder (144'-2") was cantilevered approximately 80' off of a 6-line trailer and driven across the bridge. The girder configuration was counterbalanced with a 22k counterweight at the opposite end.
Pull-Up Gantries with a W14x398 header beam were placed at each end of the girder configuration; the 398 beam had Barnhart's slide track welded to the top flange. The ends of the 5 ft girder were set atop the rocker assembly on the slide shoe for the slide track. The pull-up gantries allowed each end to be raised/lowered. The rocker assembly did not restrict rotation of the girder over the long span and the slide track allowed for left/right movements.