Lattice crawler for bridge projects9 October 2019
A Link-Belt 238 HSL lattice crawler has been used by infrastructure contractor i+iconSoutheast for multiple Virginia Department of Transportation bridge projects on the Blackwater River, near Wakefield, Virginia. The 150USt (136t) cranes was rented from Link-Belt Mid-Atlantic.
From a temporary 300ft (91.4m) long trestle, built within right-of-way space of the existing bridge, the 238 HSL demolishes the old bridge, drives up to 80ft long piles, and lifts into place new structural beams.
The batter pile angle is set using one template guide just above water level, and a second ten feet above. Two bridge abutments and five piers support a six span concrete girder bridge, with each pier consisting of six piles and a pier cap. For pile soil displacement, a vibratory hammer with 8,000lbs (3.6t) capacity force is attached to a tubular stem for pilot holes prior to pile installation. A smaller crawler lifts 20sq in concrete pile and places these into the leads of the diesel hammer. The 238 HSL then lifts a 26,000lbs diesel hammer with 88ft long leads at the same angle. Once the pile has been driven, the 238 lifts beams weighing up to 33,000lbs at an 80ft radius, turns 160° and lays them on the trestle.
In addition to pile driving work, the 238 HSL is used for concrete bucket work, pier cap rebar cages, and prefabricated formwork to complete bridge pier caps. Finally 48,000lbs concrete slabs forming the bridge deck are placed, six panels for each of the six spans.