摘要
为研究锈蚀对核安全壳结构钢衬里撕裂的影响,该文对36个不同锈蚀率的钢衬里板进行了单轴拉伸试验,分析了锈蚀钢衬里板的力学性能退化机理和退化规律;建立了锈蚀钢衬里板的本构模型;根据试验结果,提出了考虑不同锈蚀率的钢衬里撕裂准则和锈蚀模拟方法;通过数值模拟,分析了锈蚀对安全壳钢衬里撕裂的影响;最后对比了该文模拟方法与美国核管理委员会(NRC)方法的差异,并给出了NRC方法中锈蚀影响系数的取值建议。结果表明:随锈蚀率增大,钢衬里板的弹性模量变化不大,但其屈服强度、峰值强度、峰值应变和断裂应变大致呈线性退化规律;该文建立的锈蚀钢衬里板的本构模型与试验结果吻合良好;随锈蚀率增大,安全壳钢衬里发生撕裂时的内压逐渐降低,且当锈蚀率为50%时,内压降低29.06%;与NRC方法相比,该文方法能直观反映不同锈蚀率对钢衬里的影响,更能接近实际锈蚀情况;对于NRC所建议的锈蚀影响系数,锈蚀率小于20%时,可取上限值,锈蚀率为20%~40%时,建议取最佳估值,而锈蚀率超过40%后,应当取下限值。该文研究工作可为安全壳钢衬里锈蚀后的性能评估提供借鉴和参考。
To study the effect of corrosion on the tearing performance of the steel liner of nuclear containment structures,36 steel liner plates with different corrosion rates are tested under uniaxial tension.The degradation mechanism and the law of mechanical properties of corroded steel liners are analyzed.The constitutive model of corroded steel liners is established.Based on the test results,a tearing criterion and a numerical simulation method for corroded steel liner are proposed.The effect of corrosion on the tearing of the steel liner of containment is analyzed by numerical simulation.Finally,the difference between the simulation method and the Nuclear Regulatory Commission(NRC)method is compared,and a suggestion on the value of the corrosion influence coefficient in the NRC method is developed.The results show that:the elastic modulus of the steel liner is not affected by corrosion,but with the increase of corrosion rate,the yield strength,peak strength,peak strain and,fracture strain show linear degradation.The constitutive model of the corroded steel liner established agrees well with the experimental results;with the increase in corrosion rate,the internal pressure at the time of steel liner tearing gradually decreases,and when the corrosion rate is 50%,the internal pressure decreases by 29.06%.Compared with the NRC simulation method,the method proposed can directly reflect the influence of corrosion on the steel liner and is closer to the actual corrosion situation.For the corrosion influence coefficient recommended by NRC,the upper bound can be selected when the corrosion rate is less than 20%.The best estimation is recommended when the corrosion rate is 20%~40%,and the lower bound should be selected when the corrosion rate exceeds 40%.The research work can provide a reference for the performance evaluation of containment with a corroded steel liner.
作者
李鑫波
贡金鑫
李文旭
LI Xin-bo;GONG Jin-xin;LI Wen-xu(Faculty of Infrastructure Engineering,Dalian University of Technology,Dalian,Liaoning 116024,China;State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian,Liaoning 116024,China)
出处
《工程力学》
EI
CSCD
北大核心
2023年第3期153-162,共10页
Engineering Mechanics
基金
国家自然科学基金项目(51978125)。
关键词
核安全壳结构
钢衬里
锈蚀
本构模型
撕裂准则
数值模拟
nuclear containment structure
steel liner
corrosion
constitutive model
tearing criterion
numerical simulation
