New runway

With around 85 million passengers a year passing through Hartsfield-Jackson Atlanta International Airport, Atlanta, US, it is the world’s busiest airport. In 2000, it started a 10-year, US$ 5.4 billion expansion programme to cope with the 120 million passengers predicted to be using it by 2010.

The programme included a new, US$ 1.2 billion, fifth runway, which opened on time and under budget this May. It is 2.75 km long with a full-length parallel taxiway and dual north-south taxiways. Crossing ten traffic lanes of Interstate 285, two-thirds is on the west side and the remainder on the east. Linking the two sections is a US$ 159.5 million bridge. This allows planes to take off/land on top of I 285. The runway bridge is 365 by 148 m, and the taxiway bridge is 137 by 137 m.

Sub-contractor Pioneer Concrete Pumping used Putzmeister truck-mounted BSF 63Z and BSF 52Z concrete pumps - 63 and 52 m of reach respectively - during construction of the bridge. Slabs skewed at 45° were pumped with concrete at the rate of about two 1860 m² slabs a week. Over 52100 m³ of concrete was needed to complete the two bridges, which feature 764 T-shaped pre-cast beams with a total length of 27450 m. The 2.06 m tall beams vary in length from 28.6 to 40.5 m. The combined bridge decks cover 67380 m² and contain 28300 m³ of concrete. The bridge structure consists of 40000 m² of cast-in-place and pre-cast walls. The runway’s interior substructure features 1 m high concrete walls, which vary in height from 10.6 to 18.3 m.