###### Abstract  
This study examined a newly developed environmentally friendly plant-based corrosion inhibitor (_Xanthin sibiricum_). The natural potential method, linear polarization method, steel weight loss method, and corrosion area method were employed to verify the inhibitor's effectiveness in chloride-containing concrete. The results indicated that _Xanthin sibiricum_ elevated the natural potential of reinforcing steel in concrete, increased its self-corrosion potential, and reduced the self-corrosion current. After three months of curing, the corrosion rate of steel without an inhibitor was approximately 47.5% faster than the experimental group, with the steel loss rate about 40% more severe. The effectiveness of the inhibitor was influenced by increased chloride content in concrete. A two-dimensional multiphase ion transport model of reinforced concrete with realistic aggregate distribution was established using the finite element method (FEM). This model simulated chloride ion transport under typical civil engineering service environments--the coupled effects of a stray current and chloride environment. A predictive formula for the residual compressive strength of reinforced concrete was derived after corrosion under various voltages and chloride ion concentrations for a specific duration. In conjunction with a pump station project operating in a similar environment, the optimal dosage of the _Xanthin sibiricum_ inhibitor for practical engineering was determined to be 2 g/L. At this dosage, the strength of reinforced concrete specimens increased by approximately 31.1%. Finally, a predictive formula for the residual compressive strength of reinforced concrete with an added inhibitor was obtained after corrosion under various voltages and chloride ion concentrations for a specific duration. The conclusions can enhance the durability and safety of concrete structures in similar projects, showing promising application prospects. reinforced concrete; stray current; chloride environment; green corrosion inhibitor; durability of concrete structures; compressive strength prediction 2024 14 6986 2024  
also eroded, exposing a larger area of the substrate and accelerating metal phase corrosion. Figure 1 illustrates the chemical reactions of chloride ion attack on the metal phase in concrete materials [2]. Additionally, chloride ions in reinforced concrete interact with one of concrete's hydration products--monosulfate (AFm). This interaction promotes the formation of corrosion by-products, namely Friedel salts [3]. This chemical reaction signifies ongoing corrosion activity. The accumulation of these salts leads to concrete volume expansion, thereby increasing the risk of damage to concrete structures. Additionally, stray currents in service environments refer to electrical currents that do not flow along designed or specified circuits. These currents induce electrochemical corrosion [4], affecting metals such as the reinforcing steel in civil engineering structures. When stray currents flow through reinforcing steel in concrete, areas with intact passive layers act as cathodes in the \"corrosion cell\", undergoing hydrogen evolution corrosion and generating hydrogen gas. This gas, unable to quickly escape from the concrete, creates hydrostatic pressure in the corrosion area. Consequently, the metal phase separates from the surrounding concrete, significantly reducing the concrete's grip and protective capacity on the metal. Conversely, areas where the metal has been depassivated expose the metal substrate, acting as anodes in the \"corrosion cell\". The metal substrate oxidizes, producing substantial corrosion products that often increase the volume of the metal phase. For instance, the volume expansion caused by various oxide products from steel corrosion increases local stress in the concrete, damaging the protective layer around the reinforcing steel. Furthermore, the presence of stray currents accelerates chloride ion transport in concrete.