Structural Characteristics and Mechanical Properties of Rock Mass in the Field of Tianwan Nuclear Power Plant, China

The structural characteristics and mechanical properties of the rock mass are important parts of the feasibility study on the nuclear power engineering field. In this study, by means of in situ investigation and statistics, the structural plane and joint fissure features of the rock mass were analyzed and discussed at different plots and different depth scopes in the Tianwan Nuclear Power engineering field, the rock mass integrality and its weathered degree were evaluated respectively, and especially, the unfavorable geological phenomena of strongly-weathered cystid existing in the field were studied. According to the results of indoor rock mechanical tests, in combination with drilling, the shallow seismic prospecting, sonic logging and point load tests, the statistical results of physical and mechanical indices of rocks at key plots of the field were analyzed, and the design parameters of the field were calculated. It provided scientific basis for the foundation design of the nuclear power plant.

Research on the attribution evaluating methods of dynamic effects of various parameter uncertainties on the in-structure floor response spectra of nuclear power plant

Consideration of the dynamic effects of the site and structural parameter uncertainty is required by the standards for nuclear power plants （NPPs） in most countries. The anti-seismic standards provide two basic methods to analyze parameter uncertainty. Directly manually dealing with the calculated floor response spectra （FRS） values of deterministic approaches is the first method. The second method is to perform probability statistical analysis of the FRS results on the basis of the Monte Carlo method. The two methods can only reflect the overall effects of the uncertain parameters, and the results cannot be screened for a certain parameter＇s influence and contribution. In this study, based on the dynamic analyses of the floor response spectra of NPPs, a comprehensive index of the assessed impact for various uncertain parameters is presented and recommended, including the correlation coefficient, the regression slope coefficient and Tornado swing. To compensate for the lack of guidance in the NPP seismic standards, the proposed method can effectively be used to evaluate the contributions of various parameters from the aspects ＆sensitivity, acuity and statistical swing correlations. Finally, examples are provided to verify the set of indicators from systematic and intuitive perspectives, such as the uncertainty of the impact of the structure parameters and the contribution to the FRS of NPPs. The index is sensitive to different types of parameters, which provides a new technique for evaluating the anti-seismic parameters required for NPPs.

Effects of Liaoning Hongyanhe Nuclear Power Plant on the Zooplankton Community in Summer of 2017

To evaluate the effects of the Hongyanhe Nuclear Power Plant on the zooplankton community in the surrounding seawater during summer, multiple environmental factors and zooplankton distribution along the east coast of Liaodong Bay were investigated in the summer of 2017. In particular, the influences of seawater temperature, salinity, and chlorophyll a(Chl a) on the zooplankton community were analyzed. Zooplankton abundances and Chl a concentrations along the east coast of Liaodong Bay showed an initial increase followed by a decrease from July to September. During the three months, the zooplankton abundance was the highest(8116.70 ind m^(-3)) in August. The Shannon-Wiener index showed a downtrend from July to September, with the average value falling from 1.65 in July to 1.50 in September. Calanus sinicus, Paracalanus parvus, copepodid, and bivalve larvae were the dominant species/groups in the three months. The effects of the nuclear power plant's outlet on the environment factors were mainly reflected in the increased seawater temperature. Redundancy analysis showed that the zooplankton community was jointly affected by seawater temperature, salinity and Chl a concentration, and the degree of this impact varied monthly. The impact of seawater temperature on the zooplankton community was stronger than that of salinity. The primary impact of the Hongyanhe Nuclear Power Plant on the structure and distribution of the zooplankton community in the surrounding seawater during the summer was increased seawater temperature, which caused a reduction in the abundance of dominant species/groups.

Ageing related events at nuclear power plants

This paper presents main results of a comprehensive study performed by the European Clearinghouse on Operating Experience Feedback of NPP with the support of IRSN (Institut de S?reté Nucléaire et de Radioprotection) and GRS (Gesellschaft für Anlagen und Reaktorsi-cherheit mbH). Physical ageing mechanisms of structure, systems and components that eventually lead to ageing related systems and components failures at nuclear power plants were the main focus of this study. The analysis of ageing related events involved operating experience reported by NPP operators in France, Germany, USA and to the IAEA/NEA International Reporting system, on operating experience for the past 20 years (i.e. 1990-2009). A list of ageing related events was populated. Each ageing related event contained in the list was analyzed and results of analysis were summarized for each commodity group for which the ageing degradation appeared to be a dominant contributor or direct cause. The most common degradation mechanisms/ageing effects for each specific component/commodity group, their risk significance and consequences to the plant performance are described. This paper provides insights into ageing related operating experience as well as recommendations to deal with the physical ageing of nuclear power plant SSC important to safety.

Assessment of Containment Structures Against Missile Impact Threats

In order to ensure the highest safety requirements, nuclear power plant structures (the containment structures, the fuel storages and transportation systems) should be assessed against all possible internal and external impact threats. The internal impact threats include kinetic missiles generated by the failure of high pressure vessels and pipes, the failure of high speed rotating machineries and accidental drops. The external impact threats may come from airborne missiles, aircraft impact, explosion blast and fragments. The impact effects of these threats on concrete and steel structures in a nuclear power plant are discussed. Methods and procedures for the impact assessment of nuclear power plants are introduced. Recent studies on penetration and perforation mechanics as well as progresses on dynamic properties of concrete-like materials are presented to increase the understanding of the impact effects on concrete containment structures.

基于SEM-AHP方法的核电厂定量人为因素评价研究

文章基于人为因素分析与分类系统,分析了115起核电厂执照运行事件报告(Licensed Operation Event Report,LOER),并对影响核电厂事件发生的人为因素进行分类,采用结构方程模型方法得出各影响因素的路径系数,两两比较得到层次分析模型的判断矩阵,进而确定各因素的权重。同时对核电厂人为因素的重要性做排序分析,找到核电厂运行过程中的安全管理薄弱环节,从而促进核电厂系统平稳运行。

基于中国场地相关谱的核电厂结构地震易损性与风险研究

随着概率地震危险性分析与分解理论与应用的发展,场地相关谱生成理论也得到了不断发展,基于中国场地相关谱的核工程等重要基础设施地震易损性与风险分析研究还较为匮乏。该文总结了标量型中国概率地震危险性分析与分解理论方法,提出了向量型中国概率地震危险性分析与分解、条件型中国概率地震危险性分析基本原理,给出了基于中国概率地震危险性分析与分解的我国场地一致危险谱、条件均值谱、广义条件均值谱和条件一致危险谱生成理论和方法,总结了基于中国场地相关谱的核电厂结构地震易损性与风险分析理论基础,以我国某核电厂厂址及核电厂安全壳结构为算例,生成算例厂址场地相关谱,计算不同场地相关谱条件下核电厂安全壳结构地震易损性与风险。分析结果表明:不同场地相关谱条件下,我国核电厂安全壳结构安全裕量都较大;基于条件均值谱计算得到的风险结果偏于不保守。

基于等效线性化的核电厂频域隔震分析方法研究

在核电构筑物土-结构相互作用(SSI)分析中常用的方法是子结构法,这是由于其采用半解析法地基模拟技术,具有求解速度快、分析系统频率稳定的优势。因此,可在隔震核电厂房楼层反应谱计算中采用子结构法。因隔震支座具有明显的非线性特征,而子结构法基于叠加原理,在求解非线性问题时具有局限性,为了能够采用子结构法求解隔震核电厂房地震响应问题,基于等效线性化理念,在子结构法中实现隔震支座非线性行为模拟,并用SAP 2000软件验证本方法的可行性。将该方法应用于不同地基参数下隔震厂房反应谱计算,将得到的反应谱与采用隔震支座等效刚度计算结果进行对比。研究结果表明,在子结构法中应用等效线性化方法得到的隔震支座滞回曲线与采用SAP2000软件得到的滞回曲线基本一致,证明该方法是可行的;与采用等效刚度计算结果相比,采用迭代收敛刚度计算出的零周期加速度变化较小,主频略降低,峰值略有提高;由于隔震系统卓越频率与场地卓越频率并不接近,因此隔震结构楼层反应谱对地基参数的变化并不敏感。

多学科视角下核电站结构健康监测人才培养

通过介绍学科融合的教育策略,讨论在核电站结构健康监测教育中引入多学科视角的重要性。通过学科融合,学生可以全面理解和解决核电站结构健康监测领域的复杂挑战。在核电站结构健康监测中,学科融合涵盖土木工程、核工程、计算机科学和数据科学等多个领域。通过学科融合的教育策略,学生不仅了解各学科的基础理论,还能够在实际项目中应用这些知识,培养跨学科思维和解决问题的能力。这种教育策略有助于为未来的工作和研究培养具备复合型能力的工程专业人才。

核电厂地下管网结构化数据建模研究

在数字化设计平台建设过程中,为了解决缺少专业设计软件的情况下少量地下管网模型的生产和集成问题,需要建立一种与设计软件解绑的建模方式。通过研究使用结构化的管网数据驱动生成三维模型的方法,实现核电厂已有地下管道和管道附属物快速逆向建模,进一步实现核电厂室外工程设计模型和施工模型的集成与应用。

校企合作背景下核电构筑物健康监测专硕人才培养的探索与实践

核电作为清洁能源的重要组成部分,对其构筑物健康监测的需求日益增加。然而,传统的专业硕士培养模式难以满足核电行业对具备实践能力和行业背景人才的需求。因此,校企合作必然成为培养核电构筑物健康监测专业硕士人才的重要途径。本文剖析了核电行业安全发展对构筑物健康监测的迫切需求,指出了目前核电构筑物健康监测专业硕士培养模式存在的局限性,并探讨了校企合作的内涵和意义。通过借鉴哈尔滨工程大学烟台研究院专硕人才培养特色举措,本文针对核电构筑物健康监测专业硕士人才培养分别从课程体系制定、实践平台搭建、双导师指导、产学研用有机结合以及质量评估和持续改进等方面探讨了实施路径。本文将为核电构筑物健康监测专硕人才培养提供一定的借鉴与参考。

Application of Planar Seismogenic Structure to the Seismotectonic Method——A Case Study in the Dayao-Yao'an Area

In seismic hazard analysis of nuclear power plant of China there is a need to identify both seismogenic structures and seismotectonic zones. In past practice,the identification of the seismogenic structures was often based on the surface active faults and characterization of linear seismic source. In a situation which shows quite strong non-random seismic activity and lacks surface active faults,it is difficult to evaluate the seismic hazard reasonably. Taking seismogenic structures in the Dayao-Yao'an area as a case study in this paper,we discuss the need and the possibility to apply the planar seismogenic structure to the seismotectonic method. We suggest that the planar seismogenic structure should be considered when applying the seismotectonic method to the seismic risk assessment of nuclear engineering in future.

单扇推拉生物屏蔽门抗震性能分析

核电厂作为特殊建筑保证其安全性至关重要,因此需要考虑在外部自然荷载作用下核电结构及设备的安全性。地震作为重大自然灾害事件,在核电厂结构建设过程中必须考虑。该文设计一种具有上下轨道的核电厂用生物屏蔽门,考虑其自重、外部风载荷和极限安全地震动载荷(SL-2),应用ANSYS分析软件对该种生物屏蔽门进行抗震分析。按照AISC N690—1994和ASME BPVC-III-1—2001对生物屏蔽门承载部件的应力进行组合与评定。结果表明该设计方案抗震性能良好,为相关工程在满足结构抗震性能基础上提高设计可靠性提供一定参考。

基于BIM与IoT的核电钢结构工程管理信息系统研究

通过对核电钢结构工程管理中遇到的问题进行分析,梳理细化核电钢结构工程管理业务流程,搭建基于BIM与IoT的核电钢结构工程管理信息系统,阐述该信息系统的主要功能,BIM技术在核电钢结构工程进度、设计、工艺、生产、安装等工作过程中的应用,以及IoT技术在核电钢结构工程日常工作过程中的应用。结果表明,通过信息系统的建设,能够规范核电钢结构工程管理流程,助力企业成功推进数字化转型。

汽机旁路调节阀的结构设计

阐述了核电机组配套汽机旁路调节阀的技术参数和工作原理,不同运行工况下的流通能力计算及调节特性的设计,对该调节阀进行特殊的结构设计及选材,并对样机进行了性能试验,结果表明该阀各项性能均达到机组运行要求。

核电厂钢板混凝土结构一字型连接节点研究

在核电厂房钢板混凝土结构设计中,SC-RC一字型对接节点是常用的构造形式。为研究该节点的受力性能,设计了4个足尺的节点试件,分析其传力机理、可靠性、破坏形态、极限承载力、极限变形能力及其在弯矩和面外剪力作用下的滞回特性,探究不同的连接构造对节点性能的影响。试验结果表明:在受力性能方面,SC-RC一字型对接墙连接节点性能取决于较弱一侧的RC构件性能;在构造措施方面,RC墙纵筋伸入SC墙40d的锚固长度是足够的,SC-RC交界面有无设置抗剪键对节点性能影响不大。

基于技术接受模型和计划行为理论的内陆核电站重启公众接受度研究

整合技术接受模型和计划行为理论,并引入感知风险和信任,建立理论模型,以湖南省桃花江核电站周边居民实地调查为基础,探讨感知有用、感知风险、主观规范、行为态度、感知行为控制和信任对公众接受内陆核电建设重启的影响。研究结果表明,感知有用、行为态度和信任对内陆核电重启公众接受度有显著正向影响,感知风险对其存在显著负向影响;内陆核电重启的公众接受度与主观规范、感知行为控制不存在显著相关性,感知有用对行为态度和信任有积极作用。

基于有限元法的核电蓄电池柜抗震分析与评估

为保证核电厂安全运行,须对应用于安全级应急后备直流电源系统的核电厂蓄电池柜进行抗震分析.以某核电厂蓄电池柜为研究对象,建立蓄电池柜的三维模型和有限元分析模型.通过模态分析得出蓄电池柜固有频率和振型,并基于模态分析计算蓄电池柜模型在安全停堆地震(safety shutdown earthquake, SSE)叠加自重荷载作用下的应力响应.蓄电池柜3种梁复合应力值均小于1,挡板结构1次弯曲加薄膜应力值为19.6 MPa,局部最大应力值为22.44 MPa,连接螺栓复合应力值接近0.根据Design and construction rules for mechanical components of PWR nuclear islands(RCC-M规范),评定蓄电池柜的梁复合应力、挡板结构应力、局部最大应力和连接螺栓复合应力相比其许用值均有较大安全裕度.本研究通过对蓄电池柜在地震叠加自重荷载下的应力响应模拟结合RCC-M准则评定蓄电池柜应力响应结果的方法,验证了蓄电池柜设计方案满足核电厂房抗震要求,从而证明了蓄电池柜能够应用于核电厂机电厂房所在楼层,为后续蓄电池柜地震试验提供有效的试验数据参考.

核岛结构温度效应分析方法讨论和建议

核电厂核岛厂房结构设计需要考虑正常运行以及事故工况下的温度作用。不同于其他类型的荷载,温度作用产生的效应会因为材料弹性模量变化、截面开裂等原因得到释放。温度作用计算方法包括简化公式法、非线性有限元分析法、折减系数法等。本文针对国际主流核电厂设计规范中提到的温度作用计算方法进行了探讨,通过算例对不同方法进行了对比分析,并给出了工程应用建议,内容可供从事核电厂结构分析的科研和设计人员参考。

华龙一号核电站半球形穹顶土建施工技术

随着华龙一号核电站采用“开顶法”施工,安装工作提前启动,内穹顶的施工便成为关系核电站冷试工作的关键线路。鉴于此种情况,卡拉奇项目部提出内穹顶施工在原施工周期6.5个月的基础上提前1个月完成的目标。介绍了卡拉奇“华龙一号”核电2号机组半球形穹顶施工中,通过合理分层控制、优化模板配置、合理钢筋下料和绑扎工序、精确测量预应力管道定位和加固等新施工技术和方法,卡拉奇2号机组半球形穹顶施工158d完成,成功实现了5.5个月的目标要求,确保了质量和安全要求,取得了较好的经济效益,同时创造了半球形穹顶施工的最快速度。