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I学位论文原创性声明本人郑重声明：所呈交的论文是本人在导师的指导下独立进行研究所取得的研究成果。除了文中特别加以标注引用的内容外，本论文不包括任何其他个人或集体已经发表或撰写的成果作品。本人完全意识到本声明的法律后果由本人承担。作者签名：年月日学位论文版权使用授权书本学位论文作者完全了解学校有关保障、使用学位论文的规定，同意学校保留并向有关学位论文管理部门或机构送交论文的复印件和电子版，允许论文被查阅和借阅。本人授权省级优秀学士论文评选机构将本学位论文的全部或部分内容编入有关数据进行检索，可以采用影印、缩印或扫描等复制手段保存和汇编本学位论文。本学位论文属于1、保密囗，在年解密后适用本授权书2、不保密囗。作者签名：年月日导师签名：年月日II摘要压力容器作为一种重要设备广泛应用于工程领域，其安全性和可靠性是现在研究的重要课题。压力容器在生产和使用过程中存在各种不确定性因素，如构件、缺陷尺寸参数的不确定性，工况载荷的随机波动，材料机械性能的随机性。本文将这些不确定性参数当作随机变量，考虑其概率分布形式，采用应力强度-干涉模型，利用一次二阶矩法，蒙特卡洛法和随机有限元法等可靠度计算方法对容器结构进行了可靠性分析，并讨论了各随机变量对可靠度结果的灵敏度。本文对无缺陷压力容器的安全评定采用弹性失效判据，利用四种不同的方法计算了圆筒形和球形压力容器的可靠度，分析比较了各方法的优缺点。对于含凹坑缺陷的压力容器，文中采用基于塑性极限的塑性失效准则，其中极限荷载采用弹塑性增量法得到，通过ANSYS软件批处理操作模拟蒙特卡洛法实现可靠性分析，并对GB/T19624-2004《含缺陷压力容器安全评定》规范中的极限载荷安全系数进行了评估。本文最后对GB/T19624-2004《含缺陷压力容器安全评定》规范中给出的含凹坑缺陷压力容器安全评定方法做出了改进，提出了基于分项安全系数的含凹坑缺陷压力容器的安全评定方法。关键字：压力容器；可靠性；应力强度-干涉模型；分项安全系数IIIAbstractPressurevesselsasimportantequipmentsarewidelyusedinengineeringfield.Theresearchandstudyoftheirsafetyandreliabilityaretheimportantissuesnow.Pressurevesselscontainallkindsofuncertaintyfactorsintheprocessanduseofproductions,suchasuncertaintyoftheparametersincomponentanddefectsize,randomfluctuationoftheworkingloadsandtherandomnessofthematerialmechanicalproperties.Inthispaper,theseuncertainparametersareconsideredasrandomvariablesmeetingspecificprobabilitydistributionform.Byasecond-ordermomentmethod,Monte-Carlomethodandrandomfiniteelementmethodthereliabilityofpressurevesselsisstudiedinthestress-strengthinterferencemodel.Andthesensitivityofthereliabilityofresulttothevariousrandomvariablesisalsodiscussed.Inthispaper,thesafetyevaluationofpressurevesselswithoutdefectisbasedontheelasticfailurecriterion.Fourdifferentmethodsareusedtocalculatethereliabilityofcylindricalandsphericalpressurevessels,andtheadvantagesanddisadvantagesofeachmethodarealsocompared.Theplasticfailurecriterionbasedonplasticlimitisappliedtothesafetyevaluationofpressurevesselscontainingpitdefects.Inthisstudy,limitloadiscalculatedbytheelastoplasticincrementalmethod.SimulationofMonte-CarlomethodtothereliabilityanalysisisrealizedbyANSYSsoftwarebatchoperation.Accordingtotheresult,theultimateloadofthesafetyfactorinGB/T19624-2004safetyassessmentofpressurevesselscontainingdefectsisalsoevaluated.Intheendofthearticle,themethodofsafetyassessmentofpressurevesselscontainingpitdefectbasedontheGB/T19624-2004safetyassessmentofpressurevesselscontainingdefectsisimprovedbyadoptingsubentrysafetycoefficient.Keywords:Pressurevessel；reliability；stress-strengthinterferencemodel；subentrysafetyfactorIV目录第1章绪论...................................................................................................................................11.1研究背景、目的和意义...................................................................................................11.2国内外压力容器安全评定与可靠性研究概况...............................................................21.2.1国外压力容器安全评定及研究概况.....................................................................21.2.2我国压力容器安全评定及研究概况.....................................................................31.2.3可靠性研究概况.....................................................................................................41.2.4存在的主要问题.....................................................................................................51.3本文研究内容...................................................................................................................6第2章结构可靠性概述及分析方法...........................................................................................82.1结构可靠性基本原理.......................................................................................................82.1.1基本随机变量.........................................................................................................82.1.2极限状态.................................................................................................................82.1.3失效概率和可靠度.................................................................................................92.1.4可靠指标...............................................................................................................102.2可靠度分析方法.............................................................................................................122.2.1一次二阶矩法.......................................................................................................122.2.2蒙特卡洛（Monte-Carlo）法..............................................................................132.2.3响应面法...............................................................................................................142.3可靠性灵敏度分析.........................................................................................................152.4本章小结.........................................................................................................................15第3章无缺陷压力容器可靠性分析.........................................................................................173.1无缺陷压力容器失效准则.............................................................................................17