Demolition of the Sixth Street Viaduct in the US city of Los Angeles is getting under way this week to create space for its replacement.

It will take nine months to remove the 84-year-old viaduct, whose concrete has suffered from alkali silica reaction. The new structure is due for completion in late 2019.

A joint venture of Skanska and Stacy & Witbeck was appointed in 2013 as the construction manager/general contractor for the US$400m viaduct replacement project. This approach was chosen as it enabled the contracting team to working closely with the new structure’s designer, HNTB, which was appointed in 2012 (link opens in new tab).

The new viaduct's concept is described as a ‘ribbon of arches’.

It has been designed to refer to and amplify the style of the original.