Kolekole Stream Bridge

Kolekole Bridge, located in Hilo, Hawaii is a 497 ft long structure that is an integral component of the Hawaii Belt Road.  Due to its close proximity to an active volcano, this bridge is subjected to high seismic activity. 

Built for the Hawaii sugar industry in the early 1900s, Kolekole is a testament to early 20th century engineering technology, steel manufacturing and construction.  As such, KSF, Inc. developed a unique retrofit to address seismic concerns while preserving the original appearance of the bridge.

Our design requires the original structure to shoulder all existing vertical dead loads and traffic loads while a cable system sustains the lateral seismic loads. The atypical cable system (high strength threaded bars) extends longitudinally along the entire bridge, along the bottom chord of the truss, below the plate girders connecting each pier and is fastened with rock anchors at the ends of the bridge. The rods are tensioned to minimize the dead weight catenary deflection and stressed when seismic loads are applied to the bridge.