Startup Thailand: A New Innovative Sacrificial Anode for Reinforced Concrete Structures

Abstract

Severe damage reinforced concrete structures affected by corrosion are increasing. The study of prevention and protection technique play an important role to cope this urgent issue. Usage of different types of surface coatings on concrete/rebar are highly depend on workmanships of construction. Thus, sacrificial anodes are offered as one of the corrosion prevention technique. The discrete sacrificial anodes are comprise of zinc metal covered with a high alkalinity mortar which sacrifices itself to protect the corrosion of rebar. The key parameter of sacrificial anode in concrete is the activating mortar. It will help the overall cathodic reaction to efficiently protect reinforcing steel. Therefore, a new sacrificial anode was then accomplished in new activating mortar components. Two different activating mortar type have been established. This research investigated the performance of the new sacrificial anodes installed in the concrete prisms, slabs, and concrete water tanks in order to explore the corrosion prevention performance as per NACE [1], ISO [2] and ASTM standards [3-4]. This experimental study was tested on ASTM G109 [3], ASTM C876 [4] and small-scale water tank suffering from chloride-induced corrosion of the reinforcement. The performance of the anodes was determined at 28 days age and 365 days after installation to assure the activating time dependency for the mortar. The results of concrete prisms and slabs revealed that the anode polarized the rebar at a significant potential. For the water tank test results, two different concrete type were conducted with exposing chloride solution and assessed using close-interval potential mapping. The results showed a good agreement with enhance the structural durability.