The “Big One” Water Park, built in 1986, is located in Alcantarilha, Algarve, and includes a set of reinforced concrete, steel, and fiberglass composite structures.

Intervention goal

The structures exhibited several anomalies. In the reinforced concrete elements, the main anomaly detected was corrosion of the reinforcement, resulting from a combination of thin concrete cover, carbonation, and chloride contamination. Localized delamination of the concrete cover and exposure of reinforcement with significant section loss were also observed. In the steel support structures of the slides, corrosion with significant section loss was detected, as well as corrosion of several bolts and connection plates of the slide gutters.

Steps and techniques used

The reconstruction of the degraded concrete sections was carried out after treatment of the reinforced concrete by removing delaminated or contaminated concrete and supplementing the reinforcement where it was heavily corroded. For final concrete protection, two coats of acrylic paint were applied. The rehabilitation intervention consisted mainly of structural repair of the reinforced concrete; repair or full replacement of all corroded metal parts; and replacement of the metal guardrail system on the Kamikaze structure. The reconstruction of degraded concrete sections was performed using dry-mix shotcrete with a dual-chamber machine.

Results

Upon completion of the rehabilitation works, the safety conditions of the structures were fully restored according to design requirements.

Additional information

Considering the type of portal frame structure involved, characterized by slender elements such as beams and columns, the repair of the reinforced concrete and treatment of metal components required special care with scaffolding, shoring, and work platforms.