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不同温度速率下桥上CRTSⅡ型板式无砟轨道热力学性能研究

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铁道学报 2024年第5期46卷 100-109页

作者：周锐陈登高朱烜刘伟斌杜彦良李世亚深圳大学极端环境绿色长寿道路工程全国重点实验室广东深圳518060 深圳铁路投资建设集团有限公司广东深圳518000 中国铁道科学研究院集团有限公司高速铁路轨道技术国家重点实验室北京100085 重庆交通大学山区桥梁与隧道工程国家重点实验室重庆400074

针对我国CRTSⅡ型板式无砟轨道的复杂温度荷载效应,重点研究不同温度速率变化对桥上CRTSⅡ型板式无砟轨道结构热力学性能的影响。通过大型环境模拟试验箱,开展简支箱梁上5块CRTSⅡ型板式无砟轨道的1∶4几何缩尺模型的温度试验,对比分析... 详细信息

针对我国CRTSⅡ型板式无砟轨道的复杂温度荷载效应,重点研究不同温度速率变化对桥上CRTSⅡ型板式无砟轨道结构热力学性能的影响。通过大型环境模拟试验箱,开展简支箱梁上5块CRTSⅡ型板式无砟轨道的1∶4几何缩尺模型的温度试验,对比分析3种环境温度变化速率下无砟轨道内的温度和应力分布特征;建立两端自由和两端约束条件下缩尺模型的热传导数值模型,验证了该数值模型的有效性,分析了两种约束条件下无砟轨道-箱梁结构的三维温度场、应力场和位移的变化规律。结果表明,随着温度变化速率下降,无砟轨道-箱梁结构的竖向位移和温度变化幅值在增大,但竖向多层的温度和位移数值在下降;结构的应力、轨道板轴力也不断增大,特别是温度变化速率从0.67℃/min下降到0.44℃/min时。此外,两端自由的纵向应力和竖向位移均比两端约束的小,但其温度要大于两端约束的,约束边界条件会加速轨道内热传递过程。

关键词：桥上CRTSⅡ型板式无砟轨道温度模拟试验温度变化速率热力学性能热传导模型不同约束条件

Conception and Exploration of Using Data as a Service in Tunnel Construction with the NATM

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Engineering 2018年第1期4卷 123-130页

作者： Bowen du yanliang du Fei Xu Peng He State Key Laboratory of Software Development Environment Beihang University Beijing 100083 China Structural Health Monitoring and Control Institute Shijiazhuang Tiedao University Shijiazhuang 050043 China Research Center of Geotechnical and Structural Engineering Shandong University Jinan 250061 China

The New Austrian Tunneling Method （NATM） has been widely used in the construction of mountain tun- nels, urban metro lines, underground storage tanks, underground power houses, mining roadways, and so on, The variation patterns of advance geological prediction data, stress-strain data of supporting struc- tures, and deformation data of the surrounding rock are vitally important in assessing the rationality and reliability of construction schemes, and provide essential information to ensure the safety and scheduling of tunnel construction, However, as the quantity of these data increases significantly, the uncertainty and discreteness of the mass data make it extremely difficult to produce a reasonable con- struction scheme; they also reduce the forecast accuracy of accidents and dangerous situations, creating huge challenges in tunnel construction safety, In order to solve this problem, a novel data service system is proposed that uses data-association technology and the NATM, with the support of a big data environ- ment, This system can integrate data resources from distributed monitoring sensors during the construc- tion process, and then identify associations and build relations among data resources under the same construction conditions, These data associations and relations are then stored in a data pool, With the development and supplementation of the data pool, similar relations can then he used under similar con- ditions, in order to provide data references for construction schematic designs and resource allocation, The proposed data service system also provides valuable guidance for the construction of similar projects.

关键词： New Austrian Tunneling Method Big data environments Data as a service Tunnel construction

Electro-elastic Fields of Piezoelectric Materials with An Elliptic Hole under Uniform Internal Shearing Forces

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Chinese Journal of Mechanical Engineering 2013年第3期26卷 454-461页

作者： du yanliang LIU Shuhong duAN Shijie LI Yanqiang Structural Health Monitoring and Control Institute Shijiazhuang Tiedao University Department of Engineering Mechanics Shijiazhuang Tiedao University Department of Adult Education Shijiazhuang Tiedao University

The existing investigations on piezoelectric materials containing an elliptic hole mainly focus on remote uniform tensile loads. In order to have a better understanding of the fracture behavior of piezoelectric materials under different loading conditions, theoretical and numerical solutions are presented for an elliptic hole in transversely isotropic piezoelectric materials subjected to uniform internal shearing forces based on the complex potential approach. By solving ten variable linear equations, the analytical solutions inside and outside the hole satisfying the permeable electric boundary conditions are obtained. Taking PZT-4 ceramic into consideration, numerical results of electro-elastic fields along the edge of the hole and axes, and the electric displacements in the hole are presented. Comparison with stresses in transverse isotropic elastic materials shows that the hoop stress at the ends of major axis in two kinds of material equals zero for the various ratios of major to minor axis lengths; If the ratio is greater than 1, the hoop stress in piezoelectric materials is smaller than that in elastic materials, and if the ratio is smaller than 1, the hoop stress in piezoelectric materials is greater than that in elastic materials; When it is a circle hole, the shearing stress in two materials along axes is the same. The distribution of electric displacement components shows that the vertical electric displacement in the hole and along axes in the material is always zero though under the permeable electric boundary condition; The horizontal and vertical electric displacement components along the edge of the hole are symmetrical and antisymmetrical about horizontal axis, respectively. The stress and electric displacement distribution tends to zero at distances far from the elliptical hole, which conforms to the conclusion usually made on the basis of Saint-Venant’s principle. Unlike the existing work, uniform shearing forces acting on the edge of the hole, an

关键词： piezoelectric material elliptic hole permeable boundary condition electro-elastic fields internal shearing forces

大型浅水湖泊高时空分辨率风场特征数值模拟研究:以巢湖为例

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水利水电技术（中英文） 2024年第2期55卷 39-49页

作者：杜飞陈凯麒刘晓波王世岩黄爱平董飞刘畅杜彦良阳星孙龙流域水循环模拟与调控国家重点实验室北京100038 中国水利水电科学研究院北京100038

【目的】大型浅水湖泊的风场是影响湖泊流场、水体富营养化和藻华运移聚集规律的关键因素之一,仅依托气象站点的观测数据难以有效捕捉湖面风场在空间和时间上的快速变化。为精细刻画湖泊高频变化风场,辨识其时空变化特征,【方法】以巢... 详细信息

【目的】大型浅水湖泊的风场是影响湖泊流场、水体富营养化和藻华运移聚集规律的关键因素之一,仅依托气象站点的观测数据难以有效捕捉湖面风场在空间和时间上的快速变化。为精细刻画湖泊高频变化风场,辨识其时空变化特征,【方法】以巢湖为研究对象,综合利用气象观测数据、全球再分析数据集和地理静态数据,通过中尺度天气预报模式和地理空间分析技术,模拟分析巢湖地区2019年高时空分辨率的风场变化过程。【结果】结果显示:巢湖区域风速由东向西、由南向北、由湖面向陆面逐渐减弱;湖面主导风向为东风和偏东风,主导风速为二级至四级,湖面平均风速在11月最大,12月次之,5月最小,不同季节湖面平均风速由大到小依次为冬季、秋季、夏季和春季。【结论】结果表明:巢湖在白天(夜晚)出现冷(暖)湖效应,其风场在早上6时和夜晚23时出现陆风和湖风转换;西半湖受湖陆风和城市热岛影响显著,在夏季会出现明显的环湖湖风锋,其湖风锋穿透内陆距离约4.7~9 km;东半湖受山谷风影响显著,在东南部山脉以东湖区易形成低风速区,在湖口附近受狭管效应易形成高风速区。通过研究成果可进一步认知巢湖区域风场特征,为巢湖水生态环境治理提供技术支撑。

关键词：巢湖风场湖陆风中尺度天气预报模式气候变化时空变化数值模拟

Design of low frequency fiber optic Fabry–Perot seismometer based on transfer function analysis

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Chinese Optics Letters 2021年第5期19卷 31-36页

作者： Huicong Li Wentao Zhang Wenzhu Huang yanliang du Optoelectronic System Laboratory Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China

We develop a low frequency fiber Fabry–Perot(F-P)seismometer based on transfer function *** seismometer structure and demodulation system accuracy are limitations of low frequency seismic *** transfer function of the F-P seismometer is analyzed,and the mass displacement spectrum(MDS)is *** provides guidance for mechanical structure design and optical interferometer analysis to achieve low *** F-P seismometer prototype is *** experiment shows that the prototype has an average noise of 6.74 ng=p Hz below 50 Hz,and its noise is less than that of the global new high noise model within 0.16–50 Hz,whose potential is considerable.

关键词： fiber optics seismometers frequency

Performance Analysis and Optimization of Energy Harvesting Modulation for Multi-User Integrated Data and Energy Transfer

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China Communications 2024年第1期21卷 148-162页

作者： Yizhe Zhao yanliang Wu Jie Hu Kun Yang School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Integrated data and energy transfer(IDET)enables the electromagnetic waves to transmit wireless energy at the same time of data delivery for lowpower *** this paper,an energy harvesting modulation(EHM)assisted multi-user IDET system is studied,where all the received signals at the users are exploited for energy harvesting without the degradation of wireless data transfer(WDT)*** joint IDET performance is then analysed theoretically by conceiving a practical time-dependent wireless *** the aid of the AO based algorithm,the average effective data rate among users are maximized by ensuring the BER and the wireless energy transfer(WET)*** results validate and evaluate the IDET performance of the EHM assisted system,which also demonstrates that the optimal number of user clusters and IDET time slots should be allocated,in order to improve the WET and WDT performance.

关键词： energy harvesting modulation(EHM) integrated data and energy transfer(IDET) performance analysis wireless data transfer(WDT) wireless energy transfer(WET)

新形势下我国科技自主创新与经济深度融合发展的思考与建议

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科技导报 2020年第14期38卷 9-10页

作者：杜彦良石家庄铁道大学大型结构健康诊断与控制研究所石家庄050043

科学技术是第一生产力,创新是引领发展的第一动力。科技深刻影响和改变着一个国家的兴衰和命运,在世界科技创新竞争日趋激烈的趋势下,我国科技创新发展机遇与挑战并存。以此次席卷全球的新型冠状病毒肺炎疫情为例,面对这场第二次世界大... 详细信息

科学技术是第一生产力,创新是引领发展的第一动力。科技深刻影响和改变着一个国家的兴衰和命运,在世界科技创新竞争日趋激烈的趋势下,我国科技创新发展机遇与挑战并存。以此次席卷全球的新型冠状病毒肺炎疫情为例,面对这场第二次世界大战结束以来最严重的全球公共卫生突发事件,世界各国人民勇敢前行,风雨同舟。在我国,疫情发生以来,以习近平同志为核心的党中央高度重视,坚持以民为本、生命至上,采取最全面最严格防控举措,带领全国人民全力以赴抗击疫情.

关键词：创新竞争科技自主创新公共卫生突发事件深度融合生命至上思考与建议第一动力以民为本

基于最敏感斜拉索张力指标的斜拉桥主梁损伤识别方法

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中国铁道科学 2014年第2期35卷 20-25页

作者：李延强赵世英杜彦良石家庄铁道大学工程力学系河北石家庄050043

斜拉桥结构主梁的损伤会引起恒载内力重分布,进而引起斜拉索张力变化。根据这一规律,结合BP神经网络算法,研究并提出基于最敏感斜拉索张力指标的斜拉桥主梁损伤识别方法。通过分析斜拉索张力对主梁损伤的敏感性,确定对主梁损伤最敏感的... 详细信息

斜拉桥结构主梁的损伤会引起恒载内力重分布,进而引起斜拉索张力变化。根据这一规律,结合BP神经网络算法,研究并提出基于最敏感斜拉索张力指标的斜拉桥主梁损伤识别方法。通过分析斜拉索张力对主梁损伤的敏感性,确定对主梁损伤最敏感的斜拉索,并将该斜拉索在主梁损伤前后的张力变化率定义为最敏感斜拉索张力指标;将主梁发生不同位置、不同程度损伤时对应的各最敏感斜拉索张力指标作为BP神经网络的输入并训练网络,根据训练误差自动确定网络的隐含层结构,由训练好的BP神经网络的输出确定主梁的损伤位置及损伤程度。以实验室独塔斜拉桥试验模型为例,采用有限元软件ANSYS建立其空间板壳有限元模型,运用给出的主梁损伤识别方法对该斜拉桥试验模型的主梁损伤进行识别,结果表明:该方法仅用1组4根斜拉索便可以较好的识别率实现对斜拉桥主梁不同位置、不同程度单点损伤的识别。

关键词：斜拉桥主梁损伤识别斜拉索张力指标神经网络敏感性分析

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分层湖库溶解氧时空特性研究进展

水利学报 2019年第8期50卷 990-998页

作者：杜彦良彭文启刘畅中国水利水电科学研究院水环境研究所

溶解氧(DO)是湖库水质管理的关键变量之一,对维持湖库生态系统平衡至关重要。受控于湖库生态、生物地球化学和物理过程的相互作用,湖库DO对气候、地理、富营养化、有机污染、水文及负荷的输入等环境压力反应敏感。随着监测技术的提高、... 详细信息

溶解氧(DO)是湖库水质管理的关键变量之一,对维持湖库生态系统平衡至关重要。受控于湖库生态、生物地球化学和物理过程的相互作用,湖库DO对气候、地理、富营养化、有机污染、水文及负荷的输入等环境压力反应敏感。随着监测技术的提高、实验分析的多样、模型工具的完善,溶解氧垂向分层机理研究也更加深入。分层湖库的表面温水层因大气复氧、光合作用等的影响DO饱和程度高,变温层DO与受透明度影响的浮游生物呼吸与光合作用、水平和表层等外部物质输入、有机物沉积过程分解等机制有关,DO垂向形态多样,其中变温层DO极小值广泛存在且成因复杂。滞温层缺氧与沉积物、初级生产力、外部输入湖库大小等有关,通过数据分析和模型手段,滞温层DO演变过程得到较好的解释。由于分层湖库影响DO时空分布的因素众多,个别因子或经验公式分析,很难对湖库DO现象做出全面精确的描述,基于机理及过程的数值模型是DO研究中必不可少的工具。针对分层湖库越来越普遍的缺氧现象,为水质和生态环境的改善提出合理的科学措施,提高水库管理,采用原位监测、经验参数、公式和数值模型等手段,揭示湖库溶解氧的演变机理,是需要继续深入研究的课题。

关键词：分层湖库溶解氧时空变化变温层溶解氧极小(MOM) 滞温层缺氧湖库缺氧