Galvashield® XP
Galvanic Systems
Discrete embedded galvanic anode for corrosion prevention in concrete repairs.
Kamehameha Highway Bridge 603
Oahu, Hawaii, United States
Iconic double-arch bridge carrying the Kamehameha Highway over the Anahulu Stream.
Work Types: Galvanic Anodes
Consultant: Nagamine Okawa Engineers
Contractor: Kaikor Construction
Known locally as the "Rainbow Bridge" for its distinctive concrete arches, Kamehameha Highway Bridge 603 has been a landmark in Haleiwa since 1921. Originally built to replace a wooden railway bridge, it now carries two lanes of traffic across the Anahulu Stream where it meets Waialua Bay. As one of Oahu’s most recognizable coastal crossings, preserving its structure and aesthetic is vital to the region.
The Problem
Although a previous rehabilitation had been performed, new concrete spalls were forming outside of prior repairs, evidence of patch-accelerated corrosion. A full corrosion condition survey, including half-cell potential testing, GPR scans, and cores taken for chloride and carbonation, revealed that corrosion was widespread. The primary cause was the structure’s exposure to atmospheric chlorides in a hot, humid coastal climate. Despite the bridge’s age, carbonation was not a contributing factor. The challenge was to mitigate corrosion while maintaining the bridge’s historic character, and without relying on ICCP, which would require ongoing monitoring and maintenance not feasible at this location.
Our Solution
To address widespread corrosion and preserve the bridge’s historic appearance, a dual-anode galvanic protection system was installed. Galvashield® Fusion® T2 anodes were embedded in areas of sound concrete with active corrosion, delivering a high initial current followed by long-term protection. In the open spalls along the lateral beams, Galvashield® XP4 anodes were used to prevent further deterioration and avoid the halo effect often seen around past repairs. This low-maintenance solution required no external power and was installed with minimal impact to the bridge’s original design.
The Result
The anode installation extended the life of both new and existing repairs while maintaining the original architectural design of the iconic Rainbow Bridge. Designed for a service life of 30+ years, the galvanic protection system provides durable, passive corrosion mitigation, ideally suited for this remote and visually sensitive site.
Technology Used
These innovative products and technologies were used on this project.
