The engineering team for the new Sixth Street Viaduct in Los Angeles celebrated a project milestone following the successful hanger installation of the first span out of 10 spans on the new viaduct.
Spanning across Freeway 101, several railroads and the Los Angeles River, the Sixth Street Viaduct replacement project is one of the largest bridge construction projects currently underway in L.A. Originally built in 1932, the iconic bridge provides a vital connection between Boyle Heights and Downtown L.A.’s Art District. In 2016, the bridge was demolished following the decision to replace the existing Sixth Street Viaduct due to the structure becoming seismically vulnerable, according to a news release from COWI—an engineering consulting group on the project team.
At 3,060-ft-long and 100-ft-wide, the redevelopment of the bridge—designed by Michael Maltzan (architect) and HNTB (structural engineer)—includes 10 network arch spans, with a total of 388 hangers supporting the bridge deck.
Appointed as the erection engineer on the project, COWI worked closely with Skanska Stacy and Witbeck (SSW) to develop a constructable erection sequence, which includes step-by-step camber and stress analyses, and hanger installation and stressing procedure of the bridge. The current construction stage concludes the hanger installation of the first span as well as the removal of the falsework underneath.
“If you consider each arch span as an individual bridge, then this essentially marks the completion of the first of 10 bridges—making this such an exciting milestone for the project,” Tobias Petschke, Senior Project Manager at COWI North America, said in a statement.
The next step of the project is the closure of the superstructure continuity followed by the hanger installation in the second span—with completion of the bridge planned for mid-2022.