Please wait a minute...
Acta Metall Sin  2021, Vol. 57 Issue (6): 811-821    DOI: 10.11900/0412.1961.2020.00326
Research paper Current Issue | Archive | Adv Search |
Stochastic Model for Surface Characterization of Structural Steel Corroded in Simulated Offshore Atmosphere
WANG Youde1,2(), ZHOU Xiaodong1,2, MA Rui2,3, XU Shanhua1,2
1.State Key Laboratory of Green Building in Western China, Xi'an University of Architecture and Technology, Xi'an 710055, China
2.Key Lab of Engineering Structural Safety and Durability, Xi'an University of Architecture and Technology, Xi'an 710055, China
3.First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
Cite this article: 

WANG Youde, ZHOU Xiaodong, MA Rui, XU Shanhua. Stochastic Model for Surface Characterization of Structural Steel Corroded in Simulated Offshore Atmosphere. Acta Metall Sin, 2021, 57(6): 811-821.

Download:  HTML  PDF(13032KB) 
Export:  BibTeX | EndNote (RIS)      
Abstract  

Steel structures exposed to offshore atmospheric environment for a long time inevitably suffer from corrosion damage. Safety assessment of corroded steel structures largely depends on the quantification of corroded surface features as the irregular corrosion characteristics are the main factors causing decline in steel mechanical properties. To investigate the structural steel corrosion characteristics in offshore atmospheric environment, accelerated corrosion tests were conducted on 16 pieces of Q235B steel plates by periodic spraying to simulate the offshore atmospheric environment. Moreover, the surface morphologies and characteristic parameters were measured and analyzed using a ST400 3D Noncontact Profilometer and a self-written algorithm. The distribution characteristics such as corrosion depth, pit depth, and aspect ratio were elucidated, and the changing laws of statistical parameters such as mean value, standard deviation, and pitting shapes were revealed. The results indicated that in the simulated offshore atmospheric environment, the structural steel corrosion process generally goes through three stages: scab, swell, and spall. The scab and swell stages are dominated by pitting corrosion, whereas, the spall stage shows the general corrosion characteristics. Moreover, the corrosion depth of structural steel in the simulated offshore atmospheric environment conforms to the normal distribution, whereas, the pit depth and aspect ratio conform to the log-normal distribution. As the degree of corrosion increases, the mean value and standard deviation of the corrosion depth, peak value of the power spectral density of the corrosion depth, and logarithmic mean value of the pit depth also gradually increase, whereas, the logarithmic mean value of the pit aspect ratio decreases. Meanwhile, at different ages, the cone pits have the highest proportion, and the pit shape gradually changes from a cylinder or a hemisphere to a cone. Finally, based on the results of the statistical analysis of the corrosion depth and pit parameters, the stochastic field model of corrosion depth and random distribution model of corrosion pits were constructed, which achieved the accurate characterization and reproduction of the surface morphology of the corroded steel in a simulated offshore atmospheric environment. The research results would lay the foundation for the establishment of an accurate stochastic model and structural reliability analysis in the natural offshore atmospheric environment.

Key words:  offshore atmospheric environment      structural steel      corrosion      surface characteristic      stochastic model     
Received:  24 August 2020     
ZTFLH:  TU511.3  
Fund: National Natural Science Foundation of China(51908455);China Postdoctoral Science Foundation(2019M653572);Scientific Research Project of Shaanxi Provincial Department of Education(19JS042)
About author:  WANG Youde, associate professor, Tel: (029)82207610, E-mail: yord.w@xauat.edu.cn

URL: 

https://www.ams.org.cn/EN/10.11900/0412.1961.2020.00326     OR     https://www.ams.org.cn/EN/Y2021/V57/I6/811

Fig.1  Corrosion features of Q235B steel specimens with different ages before (b1-i1) and after (b2-i2) descaling
Fig.2  Comparisons between the corrosion losses of steel under accelerated and natural[17] offshore atmospheric environment (Δte / 2 refers to the single-sided equivalent thickness loss, which is equal to ηT0 / 2; η is the mass loss ratio, and T0 is the initial thickness)
Fig.3  Surface morphologies of corroded specimens (z is the corrosion depth relative to the vertex of surface)
Fig.4  Statistical results of corrosion depth of corroded specimens

Sample

No.

Δte

μm

Δtave

μm

tsd

μm

ab

Pd

cm-2

μhσhμArσAr
S1-111458241.6181.06215.34.550.242.210.44
S1-211962261.8671.03119.84.230.152.190.41
S2-1374157782.3691.58321.95.330.191.600.50
S2-2379192872.4581.63519.05.490.331.530.55
S3-15522121012.1241.37418.55.640.251.330.61
S3-2540160872.2151.38215.65.400.381.490.63
S4-1582227722.2711.50118.05.620.221.310.62
S4-26022341291.5350.84413.45.560.471.500.47
S5-16922611213.3061.95523.05.600.481.560.55
S5-2698210761.3380.85324.15.720.171.370.39
S6-17962671072.6441.59825.15.970.261.190.55
S6-2808207952.4291.44221.85.660.271.190.50
S7-110912931092.5311.54621.15.950.231.070.59
S7-211443951262.6131.60920.96.280.130.810.61
S8-113873601072.4381.46923.56.220.170.790.54
S8-214343971282.0241.19819.06.380.140.740.48
Table 1  Corrosion depth parameters and pitting characteristic parameters
Fig.5  Changing laws of Δtave relative to Δte (a) and tsd relative to Δtave (b)
Fig.6  Fitting results of power spectral density (PSD) of corroded specimens (ω1 and ω2—wave numbers corresponding to x and y axes, respectively)
Fig.7  Changing laws of a relative to Δtave (a) and b relative to a (b)
Fig.8  Extracted results of pit depth (h) and aspect ratio (Ar)
Fig.9  Changing laws of μh (a) and μAr (b) relative to Δtave
Fig.10  Pitting shape analyses (hmax—maximum depth of pits; h / hmax—relative depth of pit; h'a, h'b, h'c, and h'd—relative depths of pits; I, II, and III—regions of cone, hemisphere, and cylinder pits divided by VB value, respectively; ①-⑥—distribution zones of the three shapes of pits in the range of different relative depths (h'a-h'b, h'b-h'c, and h'c-h'd))
Fig.11  Reconstructed surfaces of structural steel corroded in offshore atmosphere based on the stochastic field model of corrosion depth (SFCD) and the random distribution model of corrosion pits (RDCP)
1 Hui Y L, Lin Z S, Li R. Experimental study and analysis on the property of corroded rebar [J]. Ind. Constr., 1997, 27(6): 10
惠云玲, 林志伸, 李 荣. 锈蚀钢筋性能试验研究分析 [J]. 工业建筑, 1997, 27(6): 10
2 Schumacher M M. Seawater Corrosion Handbook [M]. New Jersey: Noyes Data Corporation, 1979: 87
3 Garbatov Y, Soares C G, Wang G. Non-linear time dependent corrosion wastage of deck plates of ballast and cargo tanks of tankers [J]. J. Offshore Mech. Arct. Eng., 2007, 129: 48
4 Melchers R E. Corrosion uncertainty modelling for steel structures [J]. J. Constr. Steel Res., 1999, 52: 3
5 Mu X, Wei J, Dong J H, et al. Electrochemical study on corrosion behaviors of mild steel in a simulated tidal zone [J]. Acta Metall. Sin., 2012, 48: 420
穆 鑫, 魏 洁, 董俊华等. 低碳钢在模拟海洋潮差区的腐蚀行为的电化学研究 [J]. 金属学报, 2012, 48: 420
6 Chen L. Study on the deterioration properties of corroded steel [D]. Xi'an: Xi'an University of Architecture & Technology, 2010
陈 露. 腐蚀后钢材材料性能退化研究 [D]. 西安: 西安建筑科技大学, 2010
7 Xu S H, Wang Y D. Estimating the effects of corrosion pits on the fatigue life of steel plate based on the 3D profile [J]. Int. J. Fatigue, 2015, 72: 27
8 Melchers R E. Pitting corrosion of mild steel in marine immersion environment-part 1: Maximum pit depth [J]. Corrosion, 2004, 60: 824
9 Melchers R E. Pitting corrosion of mild steel in marine immersion environment-part 2: Variability of maximum pit depth [J]. Corrosion, 2004, 60: 937
10 Wang Y W. Ultimate strength of ship structures with corrosion wastage [D]. Shanghai: Shanghai Jiao Tong University, 2008
王燕舞. 考虑腐蚀影响船舶结构极限强度研究 [D]. 上海: 上海交通大学, 2008
11 Wang Y W, Huang X P, Cui W C. Pitting corrosion model of mild and low-alloy steel in marine environment-part 1: Maximum pit depth [J]. J. Ship Mech., 2007, 11: 577
王燕舞, 黄小平, 崔维成. 船舶结构钢海洋环境点蚀模型研究之一: 最大点蚀深度时变模型 [J]. 船舶力学, 2007, 11: 577
12 Silva J E, Garbatov Y, Soares C G. Ultimate strength assessment of rectangular steel plates subjected to a random localised corrosion degradation [J]. Eng. Struct., 2013, 52: 295
13 Qiu B. The study on surface characteristics and eccentric compressive load-capacity of corroded H-shape steel members at neutral salt fog environment [D]. Xi'an: Xi'an University of Architecture & Technology, 2014
邱 斌. 中性盐雾环境下锈蚀H型钢表面特征及偏压承载性能研究 [D]. 西安: 西安建筑科技大学, 2014
14 Wang R H, Shenoi R A, Sobey A. Ultimate strength assessment of plated steel structures with random pitting corrosion damage [J]. J. Constr. Steel Res., 2018, 143: 331
15 Wang Y D, Xu S H, Li H, et al. Surface characteristics and stochastic model of corroded structural steel under general atmospheric environment [J]. Acta Metall. Sin., 2020, 56: 148
王友德, 徐善华, 李 晗等. 一般大气环境下锈蚀结构钢表面特征与随机模型 [J]. 金属学报, 2020, 56: 148
16 He J X, Qin X Z, Yi P, et al. Corrosion exposure study on Q235 steel in marine atmospheric [J]. Surf. Technol., 2006, 35(4): 21
何建新, 秦晓洲, 易 平等. Q235钢海洋大气腐蚀暴露试验研究 [J]. 表面技术, 2006, 35(4): 21
17 Liang C F, Hou W T. Sixteen-year atmospheric corrosion exposure study of steels [J]. J. Chin. Soc. Corros. Prot., 2005, 25: 1
梁彩凤, 侯文泰. 碳钢、低合金钢16年大气暴露腐蚀研究 [J]. 中国腐蚀与防护学报, 2005, 25: 1
18 Melchers R E. Probabilistic models for corrosion in structural reliability assessment [J]. J. Offshore Mech. Arct., 2003, 125: 272
19 Wang Y K, Wharton J A, Shenoi R A. Ultimate strength analysis of aged steel-plated structures exposed to marine corrosion damage: A review [J]. Corros. Sci., 2014, 86: 42
20 Melchers R E, Ahammed M, Jeffrey R, et al. Statistical characterization of surfaces of corroded steel plates [J]. Mar. Struct., 2010, 23: 274
21 Li C G. Characterization of 3D surface micro-topography by 2D power spectrum [J]. Acta Metrol. Sin., 2004, 25: 11
李成贵. 三维表面微观形貌的二维功率谱表征 [J]. 计量学报, 2004, 25: 11
22 Liang S X, Sun W L, Li J. Simulation of multi-dimensional random fields by stochastic harmonic functions [J]. J. Tongji Univ. (Nat. Sci.), 2012, 40: 965
梁诗雪, 孙伟玲, 李 杰. 随机场的随机谐和函数表达 [J]. 同济大学学报(自然科学版), 2012, 40: 965
23 Wang Y D, Xu S H, Wang H, et al. Predicting the residual strength and deformability of corroded steel plate based on the corrosion morphology [J]. Constr. Build. Mater., 2017, 152: 777
24 Chen J B, Li J. Stochastic harmonic function and spectral representations [J]. Chin. J. Theor. Appl. Mech., 2011, 43: 505
陈建兵, 李 杰. 随机过程的随机谐和函数表达 [J]. 力学学报, 2011, 43: 505
25 Shinozuka M, Deodatis G. Simulation of multi-dimensional Gaussian stochastic fields by spectral representation [J]. Appl. Mech. Rev., 1996, 49: 29
[1] ZHENG Liang, ZHANG Qiang, LI Zhou, ZHANG Guoqing. Effects of Oxygen Increasing/Decreasing Processes on Surface Characteristics of Superalloy Powders and Properties of Their Bulk Alloy Counterparts: Powders Storage and Degassing[J]. 金属学报, 2023, 59(9): 1265-1278.
[2] LI Xiaohan, CAO Gongwang, GUO Mingxiao, PENG Yunchao, MA Kaijun, WANG Zhenyao. Initial Corrosion Behavior of Carbon Steel Q235, Pipeline Steel L415, and Pressure Vessel Steel 16MnNi Under High Humidity and High Irradiation Coastal-Industrial Atmosphere in Zhanjiang[J]. 金属学报, 2023, 59(7): 884-892.
[3] CHEN Runnong, LI Zhaodong, CAO Yanguang, ZHANG Qifu, LI Xiaogang. Initial Corrosion Behavior and Local Corrosion Origin of 9%Cr Alloy Steel in ClContaining Environment[J]. 金属学报, 2023, 59(7): 926-938.
[4] SI Yongli, XUE Jintao, WANG Xingfu, LIANG Juhua, SHI Zimu, HAN Fusheng. Effect of Cr Addition on the Corrosion Behavior of Twinning-Induced Plasticity Steel[J]. 金属学报, 2023, 59(7): 905-914.
[5] ZHANG Qiliang, WANG Yuchao, LI Guangda, LI Xianjun, HUANG Yi, XU Yunze. Erosion-Corrosion Performance of EH36 Steel Under Sand Impacts of Different Particle Sizes[J]. 金属学报, 2023, 59(7): 893-904.
[6] WANG Zongpu, WANG Weiguo, Rohrer Gregory S, CHEN Song, HONG Lihua, LIN Yan, FENG Xiaozheng, REN Shuai, ZHOU Bangxin. {111}/{111} Near Singular Boundaries in an Al-Zn-Mg-Cu Alloy Recrystallized After Rolling at Different Temperatures[J]. 金属学报, 2023, 59(7): 947-960.
[7] ZHAO Pingping, SONG Yingwei, DONG Kaihui, HAN En-Hou. Synergistic Effect Mechanism of Different Ions on the Electrochemical Corrosion Behavior of TC4 Titanium Alloy[J]. 金属学报, 2023, 59(7): 939-946.
[8] WU Xinqiang, RONG Lijian, TAN Jibo, CHEN Shenghu, HU Xiaofeng, ZHANG Yangpeng, ZHANG Ziyu. Research Advance on Liquid Lead-Bismuth Eutectic Corrosion Resistant Si Enhanced Ferritic/Martensitic and Austenitic Stainless Steels[J]. 金属学报, 2023, 59(4): 502-512.
[9] WANG Jingyang, SUN Luchao, LUO Yixiu, TIAN Zhilin, REN Xiaomin, ZHANG Jie. Rare Earth Silicate Environmental Barrier Coating Material: High-Entropy Design and Resistance to CMAS Corrosion[J]. 金属学报, 2023, 59(4): 523-536.
[10] HAN En-Hou, WANG Jianqiu. Effect of Surface State on Corrosion and Stress Corrosion for Nuclear Materials[J]. 金属学报, 2023, 59(4): 513-522.
[11] XU Linjie, LIU Hui, REN Ling, YANG Ke. Effect of Cu on In-Stent Restenosis and Corrosion Resistance of Ni-Ti Alloy[J]. 金属学报, 2023, 59(4): 577-584.
[12] LIAO Jingjing, ZHANG Wei, ZHANG Junsong, WU Jun, YANG Zhongbo, PENG Qian, QIU Shaoyu. Periodic Densification-Transition Behavior of Zr-Sn-Nb-Fe-V Alloys During Uniform Corrosion in Superheated Steam[J]. 金属学报, 2023, 59(2): 289-296.
[13] CHANG Litao. Corrosion and Stress Corrosion Crack Initiation in the Machined Surfaces of Austenitic Stainless Steels in Pressurized Water Reactor Primary Water: Research Progress and Perspective[J]. 金属学报, 2023, 59(2): 191-204.
[14] XIA Dahai, JI Yuanyuan, MAO Yingchang, DENG Chengman, ZHU Yu, HU Wenbin. Localized Corrosion Mechanism of 2024 Aluminum Alloy in a Simulated Dynamic Seawater/Air Interface[J]. 金属学报, 2023, 59(2): 297-308.
[15] HU Wenbin, ZHANG Xiaowen, SONG Longfei, LIAO Bokai, WAN Shan, KANG Lei, GUO Xingpeng. Corrosion Behavior of AlCoCrFeNi2.1 Eutectic High-Entropy Alloy in Sulfuric Acid Solution[J]. 金属学报, 2023, 59(12): 1644-1654.
No Suggested Reading articles found!