The firm is employing a barge-mounted MLC300 equipped with the sophisticated variable position counterweight (VPC) technology, which is said to allow the MLC300 to adjust its counterweight during each lift and keep the barge stable while lifting. When Manitowoc introduced its VPC system, one of the important selling points was the crane’s barge capabilities. The reduced footprint and floating counterweight better suits the machine to barge-mounting. Contracting teams can fit the crane onto smaller barges as the machine adjusts its centre of gravity for each lift.
The job is to replace the 756.6m-long Savanna-Sabula Bridge and the Illinois DOT hired the Plain, Wisconsin-based company to construct the new bridge. Spanning the Mississippi River between Savanna and the island community of Sabula, Iowa, the project involves the construction of two 300.4m-long outer plate girder spans and a central 166.4m-long tied-arch span. During planning, Kraemer realised that a barge-mounted crane solution would be necessary to access the lifts for the tied-arch span.
The company sought consultation from Dawes Rigging & Crane Rental (Dawes) about a crane that could be mounted on the tight working quarters of a barge, but still provide high-capacity lifting.
Milwaukee-based Dawes suggested a crane that could automatically adjust its counterweight to provide greater stability for each lift but with a smaller footprint than earlier cranes. The MLC300 was selected for the job and is now erected on a barge measuring 21.3m by 59.4m in the Mississippi River. It is lifting 68.5tonne arch rib sections to a height of 50.3m using 89.9m of main boom, all from a 30.5m radius. To meet the lift radius and pick weight requirements on the job, Kraemer’s MLC300 had to be outfitted with its optional VPC-MAX attachment, which enhances the crane’s capacity and enables additional boom and jib length combinations.
Kraemer rented the MLC300 from Dawes Rigging & Crane Rental, a member of the ALL Family of Companies.
Construction of the $80 million Savanna-Sabula Bridge replacement began in March of 2017 and is on schedule for completion in 2018. The new bridge will span 750.7m in length and will meet modern-day deck-width standards to improve the flow of two-lane traffic.
