Se the chloride content material in the groundwater. Three groundwater samples have been taken from each website place and maintained in clean one hundred mL bottles. Additional, an ICS-1500 ion chromatograph was applied to Figure out the chloride ion content in groundwater. Firstly, the common solutions of five mg/L, 10 mg/L, 20 mg/L andMaterials 2021, 14,coastal cities, all of which accelerate subway tunnel corrosion. In addition, chlorides also can penetrate through the concrete cover to induce the Charybdotoxin site corrosion of reinforcing steel and thus deteriorate the reinforced concrete structures. Quite a few Qingdao subway tunnels have been selected as the sample to analyse the chloride content material in the groundwater. Three groundwater samples had been taken from each and every web-site location and maintained in clean 100 mL bottles. 3 of 15 Additional, an ICS-1500 ion chromatograph was applied to determine the chloride ion content material in groundwater. Firstly, the regular options of 5 mg/L, 10 mg/L, 20 mg/L and 50 mg/L have been configured. Then, the sample option was diluted to ascertain the chloride ion content were configured. Then, the sample answer was diluted to figure out the chloride 50 mg/L (Figure 1) as ion content (Figure 1) as = A (1) = AD (1)where is definitely the chloride ion mass content within the water samples (mg/L), A is the chloride ion exactly where is the chloride ion mass content in the water samples (mg/L), A is the chloride ion content material thethe water sample on the common chloride ion curve and D may be the several content in in water sample around the regular chloride ion curve and D will be the several of of dilution. dilution.Figure 1. Determination of chloride ion content material in subway service environments. Figure 1. Determination of chloride ion content in subway service environments.The chloride ion concentration in groundwater was measured in following the Code The chloride ion concentration in groundwater was measured in following the Code for Investigation of Geotechnical Engineering (GB 50021-2009). Among them, the chloride for Investigation of Geotechnical Engineering (GB 50021-2009). Among them, the chloride ion around the concrete in the steel corrosion level was divided into 4 levels. The precise ion on the concrete inside the steel corrosion level was divided into four levels. The precise division is presented in Table 1. division is presented in Table 1.Table 1. Evaluation of chloride ion concentration on corrosion of steel reinforcement. Table 1. Evaluation of chloride ion concentration on corrosion of steel reinforcement.Corrosion Level Corrosion Level Micro-corrosion Micro-corrosion Weak corrosion Weak corrosion Moderate corrosion Moderatecorrosion High corrosion Higher corrosionChloride Ion Concentration in Groundwater (mg/L) Chloride Ion Concentration in Groundwater (mg/L) Long-Term Immersion Alternating Wet and Dry Cycles Long-Term Immersion Alternating Wet and Dry Cycles 10,000 100 10,000 one hundred 10,0000,000 10000 ten,0000,000 10000 – 500000 500000 – 5000 Figure 2 shows the Seclidemstat manufacturer distribution with the ion detection benefits of 66 chosen water samples from Qingdao subway tunnels. Considering long-term immersion, the corrosion of water samples could be classified as micro-corrosion and weak corrosion. The results show that 60 (90.9 ) samples may very well be classified as micro-corrosive, whereas the remaining six samples may very well be classified as weakly corrosive. The corrosion classification determined from alternating wet and dry cycles could be divided into micro-corrosion, weak corrosion, moderate corrosion and high corro.