Bridging the Red River

The initial assembly of the five cranes, as well as some jacking-up operations, were carried out by a team of Linden Comansa technicians who moved to Hanoi from Spain for the job. As all the pylons were of similar dimensions the cranes were erected with the same settings: jib length of 50m and 11 tower sections, to reach a freestanding height of 63.8m.

Linden Comansa said that the erection of three of the five cranes was especially complicated, as the pylons were completely surrounded by the water of the Red River. The lifting of the sections had to be done by crawler cranes located in barges on the fast-flowing river, making made the maneuvers more difficult.

As the pylons were being built each of the cranes had a first tie at a height of 31.1m. The 21LC550's were climbed using a hydraulic cage, to a height under hook of 85.8m. With the added height of the foundations, the cranes reached to 107.8m, high enough to finish building the pylons of between 109m and 111m.

The five tower cranes have worked at the jobsite since 2009, raising all the necessary materials for the construction of the pylons, such as formwork, prefabricated rebar cages, concrete. The 21LC550s have also helped to unroll and place the cables of the bridge, as well as to raise the cable anchor boxes to the top of the pylons. The 29 red pieces of anchor boxes per pylon were directly embedded into the concrete, weighing a maximum of 18t per piece, forcing the cranes to employ 100% of their maximum load capacity.

The main steel girders of the bridge deck, weighing up to 7t, were lifted at a 50m radius by the 21LC550s from the barge or ground to the bridge deck area.