Customer

Denzai Engineering

Location

Narita City, Chiba, Japan

Challenge

The extension of Runway B at Narita Airport required the creation of a new grade-separated intersection between the Higashi-Kanto Expressway and the extended section of Runway B.

Removal of the 150 ton overpass bridge was to allow the Higashi-Kanto Expressway to be temporarily rerouted during the intersection construction.

Products

JS-250 Jack-Up System

Solution

Lack of space prevented the use of a crane for the bridge removal, so Denzai chose to use the JS-250 Jack up system for its lifting capacity, stability and compactness. Two JS-250 towers were mounted on each of two SPMTs and a steel support platform placed on top. The platform was used to support the 21 meters length and 5 meters wide bridge deck as it was lifted and transported to a rigging location near the Expressway.

The Enerpac JS-Series jack-up system is a multi-point lifting system comprising four jack-up towers, one positioned under each corner of a load. The lifting frame of each jack-up tower contains four hydraulic cylinders, which lift and stack steel barrels. The load is lifted in increments as barrels are inserted via an automated system and stacked, forming the lifting towers. Managed by a single operator, each tower’s lifting and lowering operations occur simultaneously, while the jack-up’s synchronous technology maintains the balance of the load.