An inspection earlier this year found deterioration on some of the Paumalu Stream Bridge’s support piers, and a plan for expedited repairs was undertaken in order to avoid further structural damage. Although the bridge was repaired as recently as 2014, it was decided to renovate rather than replace the structure in order to minimise the impact on the public. Kamehameha Highway is one of the busiest routes around Oahu for residents, businesses and visitors. A bridge replacement would have required a full closure for up to two years, so the Acrow solution was chosen.

The temporary structure is a standard Acrow bridge with special floor beams and support steel underneath that wraps around the existing bridge and provides the support needed to allow continued traffic flow during the rehabilitation. With the support of the bridge and columns in place, Hawaii Department of Transportation employees have been able to safely work on the construction and installation of collars for the support piers.

It is expected that the Acrow structure will remain in place until a formal repair can be arranged, which may take several years. The project posed many challenges from detail engineering to fit up to the old 1927 bridge and a complicated installation of the structure while live traffic was still using the old bridge. Using innovative installation techniques, the Acrow structure was assembled with a truss line on each side of the old bridge and rolled into position, then the support beams were installed underneath along with the special support members for the old bridge.

“This project is a great example of how Acrow modular systems bring creative bridging solutions to difficult infrastructure situations, providing value to contractors and government agencies alike,” says Acrow president and CEO Bill Killeen. The bridge was ordered by HDOT through its emergency contracted construction company Kaikor Construction.