Five Linden Comansa towers have finished work on the project to build concrete pylons for the Nhat Tan Bridge which crosses the Red River in Vietnam.
The bridge is part of a new road that is being constructed to link Vietnam’s capital Hanoi and Noi Bai International Airport. The road is made up of eight lanes, four for each direction. It is being constructed by joint venture company IHI Infrastructure Systems and Sumitomo Mitsui Construction, both based in Japan.
Construction work on the the Nhat Tan Bridge, which is also known as the Vietnam-Japan Friendship Bridge, began in 2009. It is 1,500 metres long and has five A-shaped concrete pylons. The pylons are positioned 300 m apart and will be connected by suspension cables.
Work on the bridge was carried out by five Linden Comansa 18 tonne capacity 21LC550 tower cranes. The cranes were supplied by Singapore Linden Comansa dealer Asia-Ted.
For the construction of the pylons the tower cranes were erected on foundations and configured with a jib length of 50 m. Due to the river, three of the five tower cranes were erected using crawler cranes positioned on barges. The additional foundations increased the cranes' height between 5 and 11 m, a company spokesperson said.
For the first part of the project the cranes were tied at a height of 31.1 m, and using a hydraulic cage, each 21LC550 was climbed to a height under hook of 85.8 m. At a later stage of the project the cranes were tied at a height of 60.6 m and configured to a final height of 107.8 m. Combined with the height of the foundations, at final configuration the cranes could reach between 109 and 111 m high, a company spokesperson added. Their height meant that the tower cranes were equipped with obstruction lights for air navigation and lightning protection. Barges were used to deliver materials and crane components to the tower cranes that were surrounded by water.
Work for the tower cranes included lifting prefabricated rebar cages, concrete and steel girders weighed 7 tonnes and were lifted at a radius of 50 m. The 21LC550s also helped place the bridge cables and lift cable anchor boxes to the top of the pylons. In total, there were 29 anchor boxes per pylon and each weighed 18 tonnes.
Hitoshi Yamaji, project manager at Sumitomo Mitsui Construction, said, “The five 21LC550 tower cranes worked well during our pylon construction without any trouble. In addition, the maintenance and technical support by their well-trained technicians were satisfactory. We got the best decision by choosing Linden Comansa cranes for our construction works; otherwise, I think it would have been difficult for us to complete our project on time.”
The Nhat Tan Bridge is expected to open in October 2014.