## 3 Results and Discussions
### Analysis of Field Test Results  
#### 3.3.1 Optimal Dosage of Xanthium sibiricum Corrosion Inhibitor in Engineering Applications  
Figure 15 shows the reinforced concrete specimen being fractured and its remnants during the field test. Figure 16a shows the compressive strength of concrete specimens with different dosages of _Xanthin sibiricum_ corrosion inhibitor at various times under the influence of stray currents and chloride salt. Figure 16b displays the standard deviation of the experimental data. The majority of the experimental data show small fluctuations. The stress loading rate during the test was 0.5 MPa/s. Figure 16: Uniaxial compressive test data: (**a**) compressive strength at different corrosion times under different concentrations of inhibitor dosage; (**b**) standard deviation. Figure 15: Samples fractured during the experiment. The figure clearly demonstrates that the addition of _Xanthium sibiricum_ extract effectively enhanced the remaining compressive strength of reinforced concrete employed in a brine environment. As the dosage increased, the compressive strength of the reinforced concrete gradually improved, with the best corrosion inhibition effect observed at a dosage of 2 g/L. Over a service period of nearly six months, the strength performance of reinforced concrete has increased by about 31.1% compared to the untreated one. When the dosage exceeded 2 g/L, the strength performance of the reinforced concrete showed a decline, reflecting that excessive addition of the corrosion inhibitor might negatively impact the strength and durability of the concrete structure. Additionally, as a control group, four separate concrete specimens underwent uniaxial compression tests after reaching the standard curing time of 28 days. The load-time curves drawn from data collected using SuperTest7.2 software are shown in Figure 17. As can be seen from the figure, when the corrosion inhibitor dosage is 2 g/L, the peak load value of reinforced concrete at maturity is the highest, reaching 1048.45 kN, corresponding to a mature uncorroded compressive strength of 43.2 MPa. When the dosages are 0 g/L, 1 g/L, and 3 g/L, the compressive strengths of concrete are, respectively, 38.6 MPa, 41.9 MPa, 42.6 MPa. 3.2 Prediction of Remaining Compressive Strength of Reinforced Concrete Containing Corrosion Inhibitor  
The remaining compressive strength of reinforced concrete specimens with different corrosion inhibitor dosages under different corrosion times was compared with the uncorroded compressive strength of the control group, as shown in Figure 18.  
Figure 17: Concrete compressive strength at maturity without corrosion. Figure 18: Comparison of compressive strength of reinforced concrete before and after corrosion. compressive strength of reinforced concrete materials after a certain corrosion time under different voltages and chloride ion concentrations. * Combined with a pumping station project serving in a similar environment, the optimal dosage of the _Xanthin sibricum_ corrosion inhibitor in practical engineering was determined to be 2 g/L. Under this dosage, the strength of reinforced concrete specimens increased by about 31.1%. Prediction formula (6) was derived for the remaining compressive strength of reinforced concrete after a certain corrosion time under different voltages and chloride ion concentrations, following the addition of the corrosion inhibitor. Conceptualization, Q.L., M.Y., J.Z. and S.Q. ; methodology, Q.L., M.Y., J.Z. and S.Q. ; software, Q.L. and M.Y. ; validation, Q.L., M.Y. and J.Z. ; formal analysis, Q.L., M.Y. and J.Z. ; data curation, Q.L., M.Y. and J.Z. ; writing--original draft preparation, Q.L. and M.Y. ; writing--review and editing, Q.L., J.Z. and M.Y. ; supervision, M.Y. and S.Q. ; project administration, M.Y. and S.Q. ; funding acquisition, S.Q. All authors have read and agreed to the published version of the manuscript.