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Engineering 2022年第10期17卷 123-139页

作者： Taotao Feng Hongfa Yu Yongshan Tan Haiyan Ma Mei Xu Chengjun Yue Department of Civil and Airport Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Materials Science and Engineering Southeast UniversityNanjing 211189China College of Civil Science and Engineering Yangzhou UniversityYangzhou 225127China

In this study,through experimental research and an investigation on large datasets of the durability parameters in ocean engineering,the values,ranges,and types of distribution of the durability parameters employed for the durability design in ocean engineering in northern China were confirmed.Based on a modified theoretical model of chloride diffusion and the reliability theory,the service lives of concrete structures exposed to the splash,tidal,and underwater zones were calculated.Mixed concrete proportions meeting the requirement of a Service life of 100 or 120 years were designed,and a cover thickness requirement was proposed.In addition,the effects of the different time-varying relationships of the boundary condition(Cs)and diffusion coefficient(Df)on the Service life were compared;the results showed that the time-varying relationships used in this study(i.e.,Cscontinuously increased and then remained stable,and Dfcontinuously decreased and then remained stable)were beneficial for the durability design of concrete structures in marine environment.

关键词： Large datasets Modified theoretical model Reliability theory Service life Boundary condition Diffusion coefficient

Service life prediction of fly ash concrete using an artificial neural network

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Frontiers of Structural and Civil Engineering 2021年第3期15卷 793-805页

作者： Yasmina KELLOUCHE Mohamed GHRICI Bakhta BOUKHATEM Geomaterials Laboratory Hassiba Benbouali University of ChlefChlefAlgiers02000Algeria Department of Civil Engineering University of SherbrookeSherbrookeJK 2R1Canada

Carbonation is one of the most aggressive phenomena affecting reinforced concrete structures and causing their degradation over time.Once reinforcement is altered by carbonation,the structure will no longer fulfill service requirements.For this purpose,the present work estimates the lifetime of fly ash concrete by developing a carbonation depth prediction model that uses an artificial neural network technique.A collection of 300 data points was made from experimental results available in the published literature.Backpropagation training of a three-layer perceptron was selected for the calculation of weights and biases of the network to reach the desired performance.Six parameters affecting carbonation were used as input neurons:binder content,fly ash substitution rate,water/binder ratio,CO_(2)concentration,relative humidity,and concrete age.Moreover,experimental validation carried out for the developed model shows that the artificial neural network has strong potential as a feasible tool to accurately predict the carbonation depth of fly ash concrete.Finally,a mathematical formula is proposed that can be used to successfully estimate the Service life of fly ash concrete.

关键词： concrete fly ash carbonation neural networks experimental validation Service life

Research on Service life Prediction Model of Concrete Structure of Sea-crossing Bridge

维普期刊数据库评论

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维普期刊数据库

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武汉理工大学学报 2010年第17期32卷 141-146页

作者： WANG C J ZHANG G Z LIU K X TU L Q LI J H QIN M Q Zhejiang Province Zhoushan Island Linking Construction Commanding Department Zhejiang 316032China Wuhan Harbor Engineering Design & Research Institute Co. Ltd Wuhan 430071China Key Lab of Large-span Bridge Construction Technology Ministry of CommunicationWuhan 430071China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

According to the chloride corrosion environment,Service life prediction model of concrete structure of sea-crossing bridge was built using modified Fick's second law and the whole probability calculation method,which was suitable for China. Furthermore,a visual Service life prediction program of concrete structure was developed by optimized Monte Carlo method. Meanwhile,life 365 program was compared,indicating reliability of the prediction program. Finally,the validity of prediction model was verified in JinTang Bridge of Zhoushan Island Mainland Linkage Project.

关键词： sea-crossing bridge concrete structure Service life prediction model verify

Service life Prediction of Lining Concrete of Subsea Tunnel under Combined Compressive Load and Carbonation

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Journal of Wuhan University of Technology(Materials Science) 2010年第6期25卷 1061-1064页

作者：陈静茹 School of Civil Engineering Qingdao Technological University

Qingdao Jiaozhou Bay subsea tunnel is the second self-built tunnel in China with the designed Service life over 100 years.The durability of lining concrete are one of an important factors to determinate the Service life of tunnel.Considering the main environmental loads and mechanical loads of subsea tunnel,the durability properties of lining concrete under combined action of compressive load and carbonation has been studied through the critical compressive load test,accelerated carbonation test,natural carbonation test and capillary suction test.The tests results show that critical compressive load apparently accelerates the carbonation and deteriorates the anti-permeability of concrete.Under the combined action of critical compressive load and carbonation,the durability of lining concrete decreases.Based on the carbonization life criteria and research results,for the high-performance concrete with proposed mix ratio,the predicted Service life of lining concrete for Jiaozhou bay subsea tunnel is about 80 years which fails to reach the required Service life.It is necessary to adopt other measurements simultaneously to improve the durability of lining concrete.

关键词： Jiaozhou Bay subsea tunnel Service life lining concrete durability carbonation property critical compressive load

Effects of Operation Conditions on Service life of Ladle Lining

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China's Refractories 2013年第1期22卷 12-16页

作者： TIAN Shouxin YU Yanwen Baoshan Iron & Steel Co. Ltd.

Effects of operation conditions such as ladle temperature, remining time of molten steel, slag basicity, slag oxidation, slag viscosity , vacuum treatment, ultra-high temperature, gas blowing and stirring, intermittent operation, and different refining equipment on Service life of ladle lining refractories were researched. The following conclusions are drawn ：（1） molten steel temperature rising, remaiaing time prolonging, slag oxidation ability enhancing, slag viscosity and basicity decreasing can aecelerate the corrosion of ladle lining ; （2） ultra-high temperature and vacuum treatment of ladle not only acceler- ate the fusion corrasion of ladle lining, but also make the carbon containing refractories react forming gases leading to more corrosion, so carbon containing refractories are not stdtable.for the smelting conditions of long term vacuum treatment and ultra-high temperature, especially carbon containing refractories added with conventional additives such as A1 and Si powders ; （ 3 ） argon blowing does not accelerate the corrosion of ladle lining obvioasly, but oxygen blowing does; （4） the corrosion degree of refractories varies with the refining equipment, and the Service life of ladle lining decreases according to a certain proportion with the refining ratio increasing.

关键词： operation condition Service life ladle lining

The discussion on the test method of Service life of the organic vapor cartridge

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The discussion on the test method of service life of the org...

Study on the mechanical properties and Service life of H13 mandrels

作者： MA Gang-liang Shanghai Institute of Work Safety Science

Based on the GB 2890-2009,this paper discussed the test method in of the Service life of the organic cartridge.The difference of the weight method and instrument method was compared.The Service life and breakthrough curves of ethanol and cyclohexane were tested,cyclohexane were proved to be more suitable challenge gas for the test.The relationship between the concentration and Service life of the cyclohexane and benzene were also be discussed.

关键词： organic vapor cartridge Service life personal protective equipment

来源： cnki会议评论

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Baosteel Technical Research 2011年第2期5卷 53-58页

作者： TIAN Yuxin LU Minghe CAI Haman ZHANG Jinghai GUO Junxia Special Steel Technology Center Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 200940 China

The microstructures and mechanical properties of H13 mandrels made by Baosteel and foreign companies were investigated in this study. Based on the comparison research, the processes were optimized, such as steelmaking, heat treatment and multiple forging processes. The quality of Baosteel mandrels was greatly improved by increasing the homogenizing of an annealing temperature and refining processes. The results of the pilot trial showed that the average number of piercing steel tubes for Baosteel mandrels was over 3000 ,which reached the level of imported mandrels.

关键词： H13 mandrel steer mechanical properties Service life

Effect of Fatigue Loading on the Mechanical Properties and Resistance of High-strength Straight-hole Recycled Pervious Concrete to Rainstorm-based Waterlogging

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Journal of Wuhan University of Technology(Materials Science) 2023年第1期38卷 141-148页

作者：朱平华 FAN Haifeng YAN Xiancui LIU Hui WANG Xinjie CHEN Chunhong Department of Civil Engineering Changzhou UniversityChangzhou 213164China

A novel high-strength straight-hole recycled pervious concrete(HSRPC)for the secondary highway pavement was prepared in this paper.This study aimed to investigate the effect of porosity(0.126%,0.502%,and 1.13%),vehicle loading stress level(0.5 and 0.8)and Service life on the resistance to rainstormbased waterlogging of HSRPC under fatigue loading.The mechanical properties of HSRPC in terms of flexural strength and dynamic elastic modulus were studied.The waterlogging resistance of HSRPC was described by surface water depth and drainage time.The microstructure of HSRPC were observed with scanning electron microscopy(SEM).Results showed that although the dynamic elastic modulus and flexural strength of HSRPC decreased with the increasing number of fatigue loading,the flexural strength of HSRPC was still greater than5 MPa after design Service life of 20 years.After 2.5×10^(5)times of fatigue loading,the permeability coefficient of HSRPC with a porosity of 0.502%and 1.13%increased by 18.4%and 22.9%,respectively;while the permeability coefficient of HSRPC with 0.126%porosity dropped to 0.35 mm/s.The maximum surface water depth of HSRPC with a porosity of 0.126%,0.502%,and 1.13%were 8,5 and 4 mm,respectively.SEM results showed that fatigue loading expanded the number and width of cracks around the tiny pores in HSRPC.

关键词： recycled pervious concrete porosity fatigue loading Service life stress level rainstorm and waterlogging

Effects of Zr content on electrochemical performance of Ti/Sn-Ru-Co-ZrO_(x)electrodes

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International Journal of Minerals,Metallurgy and Materials 2022年第12期29卷 2181-2188页

作者： Linhui Chang Sheng Chen Xionghui Xie Buming Chen Haihong Qiao Hui Huang Zhongcheng Guo Ruidong Xu Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Research Center of Metallurgical Electrode Materials Engineering Technology Kunming 650106China Kunming Hendera Science and Technology Co. Ltd.Kunming 650106China North Night Vision Technology Research Institute Group Co. Ltd.Optical CompanyKunming 650093China

The low cell voltage during electrolytic Mn from the MnCl_(2) system can effectively reduce the power consumption.In this work,the Ti/Sn−Ru−Co−Zr modified anodes were obtained by using thermal decomposition oxidation.The physical parameters of coatings were observed by SEM(scanning electron microscope).Based on the electrochemical performance and SEM/XRD(X-ray diffraction)of the coatings,the influence of Zr on electrode performance was studied and analyzed.When the mole ratio of Sn−Ru−Co−Zr is 6:1:0.8:0.3,the cracks on the surface of coatings were the smallest,and the compactness was the best due to the excellent filling effect of ZrO_(2)nanoparticles.Moreover,the electrode prepared under this condition had the lowest mass transfer resistance and high chloride evolution activity in the 1mol%NH_(4)Cl and 1.5mol%HCl system.The Service life of 3102 h was achieved according to the empirical formula of accelerated-life-test of the new type anode.

关键词： Ti/Sn−Ru−Co−Zr anode electrochemical Mn electrowinning manganese chloride system Service life

INFLUENCE FACTOR ON Service life AND life EXPECTANCY OF CONCRETE

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INFLUENCE FACTOR ON SERVICE LIFE AND LIFE EXPECTANCY OF CONC...