粉煤灰水泥浆内部钢筋钝化行为的电化学试验研究

doi:10.12068/j.issn.1005-3026.2025.20249028

摘要/Abstract

摘要：

为了研究粉煤灰水泥浆内部钢筋钝化过程，考虑5组粉煤灰掺量（质量分数为0，10%，20%，30%和40%），浇筑水泥浆钢筋圆柱形试件，采用开路电位、电化学阻抗谱等电化学方法，监测水泥水化过程中内部钢筋钝化膜的形成过程，获得水泥水化过程中不同粉煤灰掺量水泥浆钢筋试件的阻抗谱，基于等效电路模型R（Q（R（QR）））得到试件钝化膜电阻、电荷转移电阻和表观界面电容等电化学参数.结果表明，粉煤灰水泥浆内部钢筋钝化膜在7 d内形成；R（Q（R（QR）））等效电路模型可有效拟合粉煤灰水泥浆钢筋试件的电化学阻抗谱曲线，卡方检验结果小于10^-4数量级；粉煤灰延缓水泥浆内部钢筋钝化；掺20%粉煤灰水泥浆内部钢筋钝化膜较稳定，对钢筋保护能力较好.

关键词: 粉煤灰, 水泥浆, 钢筋钝化, 电化学阻抗谱, 等效电路模型

Abstract:

In order to investigate the passivation process of steel bars embedded in fly ash（FA）cement paste， five FA dosages（0， 10%， 20%， 30% and 40%） were taken into consideration. The cement paste-cylindrical steel bar specimens were prepared. Open-circuit potential and electrochemical impedance spectroscopy methods were applied to monitor the formation of the passivation film on the steel bar during the cement hydration process. The impedance spectra of cement paste-steel bar specimens with different FA dosages were obtained during the cement hydration process. Based on the equivalent circuit model R（Q（R（QR）））， the electrochemical parameters such as the resistance of the passivation film， the charge transfer resistance， and the apparent interface capacitance of the specimens were recorded. The results indicate that the passivation film is formed on the steel bars embedded in the FA cement pastes within seven days. The R（Q（R（QR）））equivalent circuit model can effectively fit the electrochemical impedance spectral curves of the FA cement paste-steel bar specimens. The chi-square test results are less than 10^-4. FA delays the passivation of the steel bars embedded in the cement paste. When 20% FA is added， the passivation film of steel bars embedded in the cement paste is more stable， and it has a better protective effect on the steel bars.

Key words: fly ash, cement paste, passivation of steel bar, electrochemical impedance spectroscopy, equivalent circuit model

中图分类号:

TU 578

范颖芳, 苏钰璇, 李秋超, 陈昊. 粉煤灰水泥浆内部钢筋钝化行为的电化学试验研究[J]. 东北大学学报（自然科学版）, 2025, 46(11): 143-153.

Ying-fang FAN, Yu-xuan SU, Qiu-chao LI, Hao CHEN. Electrochemical Experimental Study on Passivation Behavior of Steel Bars Embedded in Fly Ash Cement Paste[J]. Journal of Northeastern University(Natural Science), 2025, 46(11): 143-153.

图/表 20

表1 水泥和FA化学组成(质量分数) (%)

Table 1 Chemical composition of cement and FA(mass fraction)

材料	CaO	SiO₂	Al₂O₃	MgO	Fe₂O₃	SO₃	K₂O	Na₂O	其他
水泥	59.30	21.91	6.27	1.64	3.78	2.41	—	—	4.69
FA	4.78	49.89	34.81	1.28	2.17	1.10	2.97	1.25	1.75

图1 水泥、FA的尺寸形貌特征（a）—水泥与FA粒径分布；（b）—FA微观形貌.

Fig.1 Dimensional and morphological characteristics of cement and FA

图2 试件制备流程

Fig.2 Specimen preparation process

图3 电化学测试装置

Fig.3 Electrochemical test device

表2 FA水泥浆pH

Table 2 pH of FA cement paste

试件

编号

FAC

图4 水化过程中试件的开路电位

Fig.4 Open-circuit potentialof specimens during cement hydration process

图5 水化过程中试件相位角图（a）—1 d；（b）—7 d；（c）—14 d；（d）—28 d.

Fig.5 Phase angle plots of specimens during cement hydration process

图6 水化过程中试件相位角峰值（a）—最大相位角值；（b）—最大相位角对应的频率.

Fig.6 Phase angle peak of specimens during cement hydration process

图7 水化过程中试件阻抗模量（a）—1 d；（b）—7 d；（c）—|Z|值.

Fig.7 Impedance modulus of specimens during cement hydration process

图8 水化过程中试件Nyquist曲线（a）—1 d；（b）—7 d.

Fig.8 Nyquist curves of specimens during cement hydration process

图9 FA水泥浆SEM微观形貌

Fig.9 SEM micromorphology of FA cement paste

图10 等效电路模型

Fig.10 Equivalent circuit model

图11 等效电路模拟与实测数据Nyquist图（a）—1 d；（b）—7 d.

Fig.11 Nyquist plots of simulated data by equivalent circuit and measured data

表3 等效电路模拟卡方检验结果

Table 3 Chi-square results by equivalent circuit simulation

龄期/d	OPC	FAC10	FAC20	FAC30	FAC40
1	3.59×10^-4	9.80×10^-5	6.80×10^-4	1.00×10^-4	1.74×10^-4
7	2.34×10^-4	7.41×10^-4	6.72×10^-4	2.18×10^-4	5.78×10^-4

图12 水化过程中试件Rbulk值

Fig.12 Rbulk of specimens during cement hydration process

图13 水化过程中试件介电常数

Fig.13 Dielectric constant of specimens during cement hydration process

图14 水化过程中试件Rf值

Fig.14 Rf of specimens during cement hydration process

图15 水化过程中试件Rct值

Fig.15 Rct of specimens during cement hydration process

表4 等效电路模拟参数值 (simulation)

Table 4 Parameter values of equivalent circuit

试件编号	龄期/d	Y₀·10^-2/(kΩ^-1·cm^-2·s^-1)	n
OPC	1	4.02	0.91
OPC	7	3.22	0.94
FAC10	1	4.09	0.91
FAC10	7	3.59	0.93
FAC20	1	4.10	0.90
FAC20	7	3.29	0.93
FAC30	1	4.66	0.93
FAC30	7	3.49	0.94
FAC40	1	4.43	0.90
FAC40	7	3.94	0.95

图16 水化过程中试件Capp值

Fig.16 Capp of specimens during cement hydration process

参考文献 35

[1]	Ghods P， Burkan Isgor O， Bensebaa F， et al. Angle-resolved XPS study of carbon steel passivity and chloride-induced depassivation in simulated concrete pore solution［J］. Corrosion Science， 2012， 58： 159-167.
[2]	Poursaee A， Hansson C M. Reinforcing steel passivation in mortar and pore solution［J］. Cement and Concrete Research， 2007， 37（7）： 1127-1133.
[3]	Rangel C M， Silva T M， da Cunha Belo M. Semiconductor electrochemistry approach to passivity and stress corrosion cracking susceptibility of stainless steels［J］. Electrochimica Acta， 2005， 50（25/26）： 5076-5082.
[4]	Hakiki N E， Da Cunha Belo M. Electronic structure of passive films formed on molybdenum-containing ferritic stainless steels［J］. Journal of the Electrochemical Society， 1996， 143（10）： 3088-3094.
[5]	李彩亭，曾光明，林玉鹏.粉煤灰活化试验研究［J］.湖南大学学报（自然科学版）， 2002， 29（1）： 93-97.
	Li Cai-ting， Zeng Guang-ming， Lin Yu-peng. Test study on activation of fly ash［J］. Journal of Hunan University （Natural Science）， 2002， 29（1）： 93-97.
[6]	Behera S K， Mishra D P， Singh P， et al. Utilization of mill tailings， fly ash and slag as mine paste backfill material： review and future perspective［J］. Construction and Building Materials， 2021， 309： 125120.
[7]	Mundra S， Criado M， Bernal S A， et al. Chloride-induced corrosion of steel rebars in simulated pore solutions of alkali-activated concretes［J］. Cement and Concrete Research， 2017， 100： 385-397.
[8]	Miranda J M， Fernández-Jiménez A， González J A， et al. Corrosion resistance in activated fly ash mortars［J］. Cement and Concrete Research， 2005， 35（6）： 1210-1217.
[9]	Koga G Y， Albert B， Roche V， et al. A comparative study of mild steel passivation embedded in Belite-Ye’elimite-ferrite and Porland cement mortars［J］. Electrochimica Acta， 2018， 261： 66-77.
[10]	Harilal M， Kamde D K， Uthaman S， et al. The chloride-induced corrosion of a fly ash concrete with nanoparticles and corrosion inhibitor［J］. Construction and Building Materials， 2021， 274： 122097.
[11]	Zheng H B， Dai J G， Poon C S， et al. Influence of calcium ion in concrete pore solution on the passivation of galvanized steel bars［J］. Cement and Concrete Research， 2018， 108： 46-58.
[12]	Wei J G， Chen R， Huang W， et al. Effect of endogenous chloride ion content and mineral admixtures on the passivation behavior of reinforcement embedded in sea-sand ultra-high performance concrete matrix［J］. Construction and Building Materials， 2022， 321： 126402.
[13]	Yao N， Zhou X C， Liu Y Q， et al. Synergistic effect of red mud and fly ash on passivation and corrosion resistance of 304 stainless steel in alkaline concrete pore solutions［J］. Cement and Concrete Composites， 2022， 132： 104637.
[14]	Geng Z， Yao N， Zhou X C， et al. Understanding the intrinsic effect of fly ash on passivity and chloride-induced corrosion of carbon steel and stainless steel in cement extract solutions［J］. Cement and Concrete Composites， 2023， 143： 105236.
[15]	史先飞，陈晓华，满成.HRB400钢在模拟混凝土孔隙液中的自然钝化行为及耐蚀性能的研究［J］.中国腐蚀与防护学报，2024， 44（5）： 1213-1222.
	Shi Xian-fei， Chen Xiao-hua， Man Cheng. Natural passivation behavior and corrosion resistance of HRB400 steel in simulated concrete pore solution［J］. Journal of Chinese Society for Corrosion and Protection， 2024， 44（5）： 1213-1222.
[16]	Society for Testing and Materials. Standard test method for half-cell potentials of uncoated reinforcing steel in concrete：［S］. United States of America： ASTM International， 2009.
[17]	Jin Z Q， Zhao X， Du Y J， et al. Comprehensive properties of passive film formed in simulated pore solution of alkali-activated concrete［J］.Construction and Building Materials， 2022， 319： 126142.
[18]	Gray J J， Orme C A. Electrochemical impedance spectroscopy study of the passive films of alloy 22 in low pH nitrate and chloride environments［J］. Electrochimica Acta， 2007， 52（7）： 2370-2375.
[19]	Rizwan Hussain R， Alhozaimy A M， Al-Negheimish A. Role of scoria natural pozzolan in the passive film development for steel rebars in chloride-contaminated concrete environment［J］. Construction and Building Materials， 2022， 357： 129335.
[20]	王潇舷，刘加平，穆松，等.混凝土环境中β-甘油磷酸钠影响钢筋阻锈行为研究［J］.华南理工大学学报（自然科学版），2024， 52（3）：28-40.
	Wang Xiao-xian， Liu Jia-ping， Mu Song， et al. Study on sodium β-glycerophosphate in concrete affects the inhibited behavior of steel bar［J］. Journal of South China University of Technology （Natural Science Edition），2024， 52（3）： 28-40.
[21]	Wang X H， Chen B， Gao Y， et al. Influence of external loading and loading type on corrosion behavior of RC beams with epoxy-coated reinforcements［J］. Construction and Building Materials， 2015， 93： 746-765.
[22]	Ababneh A， Sheban M. Impact of mechanical loading on the corrosion of steel reinforcement in concrete structures［J］. Materials and Structures， 2011， 44（6）： 1123‒1137.
[23]	Monticelli C， Natali M E， Balbo A， et al. Corrosion behavior of steel in alkali-activated fly ash mortars in the light of their microstructural， mechanical and chemical characterization［J］. Cement and Concrete Research， 2016， 80： 60-68.
[24]	Tan Y S， Yu H F， Bi W L， et al. Hydration behavior of magnesium oxysulfate cement with fly ash via electrochemical impedance spectroscopy［J］.Journal of Materials in Civil Engineering， 2019，31（10）： 04019237.
[25]	Sánchez M， Gregori J， Alonso C， et al. Electrochemical impedance spectroscopy for studying passive layers on steel rebars immersed in alkaline solutions simulating concrete pores［J］. Electrochimica Acta， 2007， 52（27）： 7634-7641.
[26]	Liu G J， Zhang Y S， Wu M， et al. Study of depassivation of carbon steel in simulated concrete pore solution using different equivalent circuits［J］. Construction and Building Materials， 2017，157： 357-362.
[27]	Lin K Q， Zheng T. Long-term corrosion behavior of low carbon steel bars embedded in building concrete： effect of silica fume and dolomite powder as partial replacements of Portland cement［J］. International Journal of Electrochemical Science， 2020， 15（12）： 12329-12338.
[28]	刘国建，朱航，张云升，等. 混凝土孔溶液中不同侵蚀离子对钢筋的腐蚀行为［J］. 硅酸盐学报， 2022， 50（2）： 413-419.
	Liu Guo-jian， Zhu Hang， Zhang Yun-sheng， et al. Corrosion behavior of steel subjected to different corrosive ions in simulated concrete pore solution［J］. Journal of the Chinese Ceramic Society， 2022， 50（2）： 413-419.
[29]	Rosalbino F， Scavino G， Ubertalli G. Electrochemical corrosion behavior of LDX 2101® duplex stainless steel in a fluoride-containing environment［J］.Materials and Corrosion， 2020，71（12）： 2021-2028.
[30]	乔宏霞，刘志超，路承功，等.碳化环境下多元胶凝体系钢筋混凝土电化学特性［J］.湖南大学学报（自然科学版）. 2023， 50（3）： 110-120.
	Qiao Hong-xia， Liu Zhi-chao， Lu Cheng-gong， et al. Electrochemical characteristics of reinforced concrete with multiple cementitious system in carbonization environment［J］. Journal of Hunan University （Natural Sciences）， 2023， 50（3）： 110-120.
[31]	Huang T J， Yuan Q， Zuo S H， et al. Evaluation of microstructural changes in fresh cement paste using AC impedance spectroscopy vs. oscillation rheology and ¹H NMR relaxometry［J］.Cement and Concrete Research， 2021，149： 106556.
[32]	席翔，储洪强，冉千平，等. 通用硅酸盐水泥基材料低频介电性能的研究进展［J］.硅酸盐学报， 2023， 51（8）： 2074-2089.
	Xi Xiang， Chu Hong-qiang， Ran Qian-ping， et al. Low-frequency dielectric behavior of common Portland cement-based materials： a review［J］. Journal of the Chinese Ceramic Society， 2023， 51（8）： 2074-2089.
[33]	Wang D Q， Liu Z C， Zhi X， et al. Passivation of mild steel embedded in low-heat Portland cement： a comparative study with ordinary Portland cement［J］. Cement and Concrete Composites， 2024， 146： 105389.
[34]	崔丽君，乔宏霞，曹锋，等.青稞秸秆灰改性氯氧镁水泥砂浆防护钢筋混凝土的损伤特性［J］.硅酸盐通报，2024， 43（9）： 3282-3293..
	Cui Li-jun， Qiao Hong-xia， Cao Feng， et al. Damage characteristics of highland barley straw ash modified magnesium oxychloride cement mortar protected reinforced concrete［J］. Bulletin of the Chinese Ceramic Society， 2024， 43（9）： 3282-3293.
[35]	Pech-Canul M A， Castro P. Corrosion measurements of steel reinforcement in concrete exposed to a tropical marine atmosphere［J］. Cement and Concrete Research， 2002， 32（3）： 491-498.