Contractors on the project used the crawler cranes to lift and gradually push steel girders across the canyon, eliminating the need for complex scaffolding.
Liebherr
Liebherr assists with major infrastructure project
The steel girders of the bridge are assembled on one side of the canyon and then gradually pushed over the deep Juneau Creek Canyon to Cooper Landing with hydraulic presses using the bridge launch technique. Using this technology, the massive individual sections can be positioned precisely without the need for complex scaffolding across the chasm.
“The most challenging lift for us was the first girders of the bridge. They were very heavy, and I had to rely on a lot of ground people because wind was coming in. We could see up to 40 mile per hour winds. So I am very happy that we therefore have two Liebherr crawler cranes — one on each side of the project,” explains Travis Ludlow, crane driver of one of the LR 1300.1 SX at Traylor Bros, Inc. He is particularly happy with the cranes’ Gradient Travel Aid for safely negotiating slopes, a major challenge with the topographical conditions of the project. The crane’s control system automatically calculates the centre of gravity and warns the operator before the crane leaves the safe area. While travelling, the operator receives real-time information about the permissible and actual gradient, and the crane’s overall centre of gravity at all times. If necessary, the main boom angle can be altered so that the machine remains in the safe area.
Decisive factors to choose a Liebherr crawler crane
Only solid steel girders are being used for the Juneau Creek Bridge. These allow for wide spans and a high load-bearing capacity with minimum material weight. The girders must be aligned with millimetre precision to achieve the necessary stability for the bridge. Traylor Bros, Inc. are carrying out this job with the two crawler cranes LR 1300.1 SX, so that the bridge can grow safely and efficiently across the canyon.
“There were several factors that went into the decision to choose the LR 1300.1 SX. The reliability of the crawler cranes is incredibly important for our project site. We have a small window before the weather kicks us out. Any malfunctions would cause massive schedule delays. The LR 1300.1 SX works when we need it. It has the versatility and the capacity to handle all the lifts we need to do,” says Tyler Becker, Senior Field Engineer at Traylor Bros, Inc.
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