Arup Group CCTV's leaning towers will be linked by a building high above Beijing streets.

With steelwork for the two leaning towers of Beijing’s 234-m-tall Chinese Central Television Headquarters building now in place, engineers are preparing to link their tops with a bridge building. The bridge, ranging in height from nine to 13 floors, will complete the looping structure containing rouhgly 100,000 tonnes of structural steel.

Occupying opposite corners of a  roughly 160x160 m footprint, the towers rise from an L-shaped podium, leaning inwards in different planes. They will be joined at the top by the L-shaped structure, that is due form completion next February, according to Rory McGowan, project director at the main structural designer Arup Group, London.

Lower floors of the roof structure will be launched like bridge trusses, cantilevering 67.2 m from one tower and 75.2 m from the other, adds McGowan. Once linked, the cantilevers will form the base for remaining steelwork erection.

Chinese subcontractors started tower erection in February 2006 and reached full height last month, reports McGowan. With curtain walling starting this February, the tower is “mainly on schedule” for completion in time for the 2008 Beijing Olympic Games, he adds.

Designed by Office for Metropolitan Architecture, the Netherlands-based firm started by Rem Koolhaus, with East China Architecture & Design Institute, Shanghai, the tower is being built by prime contractor China State Construction Engineering. Project cost is estimated at about $620 million but no formal figure is available.