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International Journal of Smart and Nano Materials 2023年第3期14卷 337-368页

作者： Huanyu Yang Zhi Zhou jinping ou Faculty of Infrastructure Engineering Dalian University of TechnologyDalianLiaoning 116024China School of Civil and Architectural Engineering Hainan UniversityHaikouHainanChina Harbin Institute of Technology(Shenzhen) School of Civil and Environmental EngineeringShenzhenGuangdongChina

As the main load bearing component,the steel strand has a significant impact on the safety of civil ***-time monitoring of steel strand stress distribution throughout the damage process is an impor-tant aspect of civil infrastructure health ***,this study proposes an optical-electrical co-sensing(OECS)smart steel strand with the DOFS and CCFPI embedded *** can simultaneously measure small strains in the initial damage phase with high accuracy and obtain information in the large deformation phase with relatively low *** experiments were carried out to test its sensing *** shows both DOFS and CCFPI have good linearity,repeatability and *** comparison to DOFS,CCFPI has a relatively lower accuracy and resolution,but a large enough measurement range to tolerate the large strain in the event of a steel strand *** verify the reliability of the proposed smart steel strand in real structures,the strand strain distribution in the full damage process of bonded prestressed beams under four-point bending loading was monitored using the smart steel strand as a prestressing *** strain measured by the OECS steel strand is shown to reflect the deformation and stiffness variation of prestressed beams under different load.

关键词： Distributed optical fiber sensor(DOFS) Coaxial cable fabry–perot interferometer(CCFPI) Smart steel strand Prestress monitoring Optical-electrical co-sensing

Development and sensing performance study of a smart CFRP cable assembled by multi-group anchorage units

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International Journal of Smart and Nano Materials 2023年第3期14卷 286-302页

作者： Lian Shao Huanyu Yang jinping ou Zhi Zhou Faculty of Infrastructure Engineering Dalian University of TechnologyDalian 116024China School of Civil Engineering Harbin Institute of TechnologyHarbinChina School of Civil Engineering and Architecture Hainan UniversityHaikouChina

Carbon fiber reinforced polymer(CFRP)can be applied for bridge cables due to its excellent *** the important load-bearing structural component,real-time force monitoring of the CFRP cable is *** paper presents a new smart CFRP cable that combines the self-sensing rods with embedded sensors and the anchorage system using extrusion *** embedding optical fiber(OF)and coaxial cable Fabry-Perot interferometer(CCFPI)into CFRP rods respectively,two types of self-sensing rods(CFRP-OF rod and CFRP-CCFPI rod)were fabricated.A new anchorage unit using an extrusion process was proposed as a basic component of smart CFRP *** units holding a CFRP-OF rod and a CFRP-CCFPI rod were tested to obtain their sensing and mechanical *** ancho-rage units were assembled to form a smart CFRP cable with self-sensing functionality.A verification test was carried out to confirm the capabil-ity of monitoring the cable *** test results demonstrate that the smart CFRP cable composed of multiple anchorage units has good potential in bridge engineering.

关键词： Carbon fiber reinforced polymer smart cable sensor extrusion process bridge engineering

Long-term performance of packaged fiber Bragg grating sensors for strain monitoring inside creep medium

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International Journal of Smart and Nano Materials 2022年第1期13卷 42-63,I0003页

作者： Huanyu Yang Ying Huang Zhi Zhou jinping ou Faculty of Infrastructure Engineering Dalian University of TechnologyDalian116024Liaoning ProvinceChina Department of Civil and Environmental Engineering North Dakota State UniversityFargoNorth DakotaUSA Hainan University School of Civil and Architectural EngineeringHaikou570228Hainan ProvinceChina School of Civil and Environmental Engineering Harbin Institute of Technology(Shenzhen)ShenzhenGuangdong ProvinceChina

To investigate the long-term performance of the packaged fiber Bragg grating(FBG)sensors embedded in civil infrastructure for strain monitoring,in this paper,the influence of host matrix’s creep effect on the behavior of the FBG sensors was systematically studied through theoretical,numerical,and experimental analysis.A theoretical strain transfer analysis between the optic fiber,packaging layer,and host matrix to consider the creep effect of the host matrix was performed accordingly for long-term strain *** studies were carried out using numerical analysis for FBG sensors packaged with glass fiber reinforced plastic(GFRP),also known as FBG-GFRP sensors in concrete,as an *** results show that embedded in a creep medium,an acceptable long-term performance of packaged FBG sensors requires the packaging layer to have a minimum length and maximum thick*** long-term creep tests using epoxy resin and concrete as host matrix for FBG-GFRP sensors also clearly demonstrated that the influence of creep effect cannot be ignored for strain measurements if the host matrix has a creep potential and the developed correction model performed well to reduce measurement errors of such sensors in creep medium.

关键词： Fiber Bragg gratings(FBG)sensor strain transfer creep packaging layer epoxy resin concrete

Nanomechanical Characteristics of Interfacial Transition Zone in Nano-Engineered Concrete

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Engineering 2022年第10期17卷 99-109页

作者： Xinyue Wang Sufen Dong Zhenming Li Baoguo Han jinping ou School of Civil Engineering Dalian University of TechnologyDalian 116024China School of Transportation and Logistics Dalian University of TechnologyDalian 116024China Department of Materials and Environment(Microlab) Faculty of Civil Engineering and GeoscienceDelft University of TechnologyDelft 2628 CNNetherlands

This study investigates the effects of nanofillers on the interfacial transition zone(ITZ)between aggregate and cement paste by using nanoindentation and statistical nanoindentation ***,the underlying mechanisms are revealed through micromechanical *** nanoindentation results indicate that incorporating nanofillers increases the degree of hydration in the ITZ,reduces the content of micropores and low-density calcium silicate hydrate(LD C-S-H),and increases the content of highdensity C-S-H(HD C-S-H)and ultra high-density C-S-H(UHD C-S-H).In particular,a new phase,namely nano-core-induced low-density C-S-H(NCILD C-S-H),with a superior hardness of 2.50 GPa and an indentation modulus similar to those of HD C-S-H or UHD C-S-H was identified in this *** modeling results revealed that the presence of nanofillers increased the packing density of LD CS-H and significantly enhanced the interaction(adhesion and friction)among the basic building blocks of C-S-H gels owing to the formation of nano-core-shell elements,thereby facilitating the formation of NCILD C-S-H and further improving the performance of the *** study provides insight into the effects of nano fillers on the ITZ in concrete at the nanoscale.

关键词： Concrete Nanofiller Interfacial transition zone Nanoindentation Micromechanical modeling Nano-core effect

Tailoring Anti-Impact Properties of Ultra-High Performance Concrete by Incorporating Functionalized Carbon Nanotubes

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Engineering 2022年第11期18卷 232-245页

作者： Jialiang Wang Sufen Dong Sze Dai Pang Xun Yu Baoguo Han jinping ou School of Civil Engineering Dalian University of TechnologyDalian 116024China School of Transportation and Logistics Dalian University of TechnologyDalian 116024China Department of Civil and Environmental Engineering National University of SingaporeSingapore 117576Singapore Department of Mechanical Engineering New York Institute of TechnologyNew YorkNY 11568USA

Replacing micro-reinforcing fibers with carbon nanotubes(CNTs)is beneficial for improving the impact properties of ultra-high performance concrete(UHPC);however,the weak wettability and dispersibility of CNTs and the weakly bonded interface between CNTs and UHPC limit their effectiveness as ***,this study aims to enhance the reinforcement effect of CNTs on the impact properties of UHPC via *** ordinary CNTs,functionalized CNTs with carboxyl or hydroxyl groups can break the Si-O-Ca-O-Si coordination bond in the C-S-H gel and form a new network in the UHPC matrix,effectively inhibiting the dislocation slip inside UHPC ***,functionalized CNTs,particularly carboxyl-fu nctionalized CNTs,co ntrol the crystallization process and microscopic morphology of the hydration products,significantly decreasing and even eliminating the width of the aggregate-matrix interface transition zone of the ***,the functionalized CNTs further decrease the attraction of the negatively charged silicate tetrahedron to Ca2+in the C-S-H gel,while modifying the pore structure(particularly the nanoscale pore structure)of UHPC,leading to the expansion of the intermediate CS-H *** changes in the microstructures of UHPC brought about by the functionalized CNTs significantly enhance its dynamic compressive strength,peak strain,impact toughness,and impact dissipation energy at strain rates of 200-800 s^(-1).Impact performance of UHPC containing a small amount of carboxyl-functionalized CNTs(especially the short ones)is generally better than that of UHPC containing hydroxyl-functionalized and ordinary CNTs;it is even superior to that of UHPC with a high steel fiber content.

关键词： Functionalized carbon nanotubes Concrete Anti-impact properties Reinforcing mechanisms

基于自感知纤维增强复合材料锚杆的隧道围岩松动圈识别

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西南交通大学学报 2024年第1期59卷 11-19页

作者：李锦辉张俊齐魏强贾大鹏郭东白石欧进萍哈尔滨工业大学(深圳)深圳市土木工程智能结构系统重点实验室广东深圳518055 中国国家铁路集团有限公司北京100844 智性纤维复合加固南通有限公司江苏南通226010

隧道围岩变形和松动圈厚度是隧道结构设计的重要考虑因素和安全运营的重要参考依据,现有的松动圈识别方法和隧道围岩变形测量手段多停留在检测层面,缺乏长期实时监测方法.为此,研发内嵌光纤的自感知纤维增强复合材料(FRP)锚杆,提出基于... 详细信息

隧道围岩变形和松动圈厚度是隧道结构设计的重要考虑因素和安全运营的重要参考依据,现有的松动圈识别方法和隧道围岩变形测量手段多停留在检测层面,缺乏长期实时监测方法.为此,研发内嵌光纤的自感知纤维增强复合材料(FRP)锚杆,提出基于内嵌光纤自感知FRP锚杆的隧道围岩智能监测系统,可以实现对围岩变形立体化、全天候的实时监测;结合监测数据与理论分析,提出隧道围岩松动圈的识别方法,并将该智能监测方法应用于广汕高铁陈塘隧道.研究结果表明:自感知FRP锚杆能够精准探知现场施工对围岩变形的影响规律,型钢钢架对隧道围岩的支护作用较为突出;监测数据可以实时反映自感知锚杆的受力规律,从而准确识别隧道不同位置围岩的松动圈厚度;基于自感知FRP锚杆的隧道围岩智能监测系统将在隧道运营过程中持续、实时监测隧道围岩的变形,为隧道全生命周期的结构安全提供高技术保障.

关键词：智能监测松动圈围岩变形光纤光栅自感知FRP锚杆

海水环境下BFRP筋-海水海砂混凝土粘结耐久性

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海南大学学报（自然科学版） 2024年第1期42卷 87-93页

作者：吴云飞常宇飞于志力周智欧进萍海南大学土木建筑工程学院海南海口570228 大连理工大学建设工程学部辽宁大连116024 哈尔滨工业大学(深圳)土木与环境工程学院广东深圳518055

对BFRP筋-海水海砂混凝土界面粘结耐久性开展长期浸泡侵蚀试验,分析真实海水浸泡后界面粘结性能的长期退化规律,浸泡时间分别是30 d、90 d、180 d、270 d、360 d、450 d、540 d和630 d.基于拉拔试验数据,对真实海洋环境下BFRP筋-海水海... 详细信息

对BFRP筋-海水海砂混凝土界面粘结耐久性开展长期浸泡侵蚀试验,分析真实海水浸泡后界面粘结性能的长期退化规律,浸泡时间分别是30 d、90 d、180 d、270 d、360 d、450 d、540 d和630 d.基于拉拔试验数据,对真实海洋环境下BFRP筋-海水海砂混凝土的长期极限粘结强度保留率进行模拟预测.结果表明:在真实海水浸泡630 d后,BFRP筋-海水海砂混凝土的极限粘结强度降低了66.13%,且0~270 d退化速率明显高于270 d以后的退化速率.采用Bank模型并引入湿度修正系数,预测50 a后在海洋环境、室外环境及室内环境条件下极限粘结强度保留率分别为31.42%、57.15%和74.85%,为BFRP筋-海水海砂混凝土构件在沿海地区建筑中的应用提供参考.

关键词： BFRP筋海水海砂混凝土拉拔试验真实海水长期性能预测

Exploring the impact of new particle formation events on PM_(2.5) pollution during winter in the Yangtze River Delta,China

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Journal of Environmental Sciences 2022年第1期34卷 75-83页

作者： jinping ou Qihou Hu Haoran Liu Shiqi Xu Zhuang Wang Xiangguang Ji Xinqi Wang Zhouqing Xie Hui Kang Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China Key Lab of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Environmental Science and Optoelectronic Technology University of Science and Technology of ChinaHefei 230026China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Institute of Polar Environment&Anhui Province Key Laboratory of Polar Environment and Global Change Department of Environment Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026China

New particle formation(NPF)events are an increasingly interesting topic in air quality and climate *** this study,the particle number size distributions,and the frequency of NPF events over Hefei were investigated from November 2018 to February *** proportions of the nucleation mode,Aitken mode,and accumulation mode were 24.59%,53.10%,and 22.30%,respectively,which indicates the presence of abundant ultrafine particles in ***-six NPF events occurred during the observation days,accounting for 41.82%of the entire observation ***,the favorable meteorological conditions,potential precursor gases,and PM_(2.5)range of the NPF events were *** to non-NPF days,the NPF events preferentially occurred on days with lower relative humidity,higher wind speeds,and higher *** the PM_(2.5) was 15–20,70–80,and105–115μg/m^(3),the frequency of the NPF events was *** mode particles were positively related to atmospheric oxidation indicated by ozone when PM_(2.5) ranged from 15 to 20μg/m^(3),and related to gaseous precursors like SO_(2) and NO_(2) when PM_(2.5)was located at 70-80 and 105–115μg/m^(3).On pollution days,NPF events did not directly contribute to the increase in the PM_(2.5) in the daytime,however,NPF events would occur during the night and the growth of particulate matter contributes to the nighttime PM_(2.5) *** could lead to pollution that lasted into the next *** findings are significant to the improvement of our understanding of the effects of aerosols on air quality.

关键词： New particle formation Aerosols PM_(2.5) Hefei Meteorological conditions

Design approaches for active,semi-active and passive control systems based on analysis of characteristics of active control force

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Earthquake Engineering and Engineering Vibration 2009年第4期8卷 493-506页

作者： ou jinping Li Hui School of Civil ＆ Hydraulic Engineering Dalian University of Technology Dalian 116024 China School of Civil Engineering Harbin Institute of Technology Harbin 150090 China

In this paper, the characteristics of forces in active control systems connected to adjacent levels of a building are analyzed. The following characteristics are observed：（1） active control can provide significantly superior supplemental damping to a building, but causes a small frequency shift; （2） the linear quadratic regulator （LQR）-based control force is composed of an elastic restoring force component and a damping force component, where the damping force is almost identical to the total control force, however, the elastic restoring force is very small; and （3） the active control forces prevent mction most of the time during the entire control process. These three characteristics imply that active control systems connected to adjacent levels of a building behave like passive damping devices with adjustable parameters, namely damping characteristics in an active control, which is the mechanism used by semi-active control devices to reach similar performance as active control systems. Two indices are defined to quantify the damping characteristics of control forces in active control systems. These two indices can also be used to quantify the capacity of semi-active control to achieve the perfonrlance of active control. Based on the above observations, two principles are founded for optimization of parameters of semi-active control devices and passive dampers. The first is that the maximum output force of a semi-active or passive device to be designed is identical to an active device, called ＂design principle＂. The other is the response equivalent principle, which states that the response of a building with semi-active or passive devices is the same as with active devices when the same maximum output force is applied. The design procedure for semi-active control devices and passive dampers is described in detail. Finally, numerical simulations of two benchmark problems is conducted to demonstrate the damping characteristics of active control and investigate the c

关键词： active control: semi-active control smart control damping design approach

Vertical distribution and temporal evolution of formaldehyde and glyoxal derived from MAX-DOAS observations:The indicative role of VOC sources

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Journal of Environmental Sciences 2022年第12期34卷 92-104页

作者： Qianqian Hong Cheng Liu Qihou Hu Yanli Zhang Chengzhi Xing jinping ou Wei Tan Haoran Liu Xiaoqing Huang Zhenfeng Wu School of Environment and Civil Engineering Jiangnan UniversityWuxi 214122China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Environmental Optics&Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China Anhui Province Key Laboratory of Polar Environment and Global Change University of Science and Technology of ChinaHefei 230026China Guangdong Key Laboratory of Environmental Protection and Resources Utilization State Key Laboratory of Organic GeochemistryGuangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou 510632China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China

Formaldehyde(HCHO)and glyoxal(CHOCHO)are important oxidization intermediates of most volatile organic compounds(VOCs),but their vertical evolution in urban areas is not well *** profiles of HCHO,CHOCHO,and nitrogen dioxide(NO_(2))were retrieved from ground-based Multi-Axis Differential Optical Absorption Spectroscopy(MAXDOAS)observations in Hefei,*** and CHOCHO vertical profiles prefer to occur at higher altitudes compared to NO_(2),which might be caused by the photochemistry-oxidation of longer-lived VOCs at higher *** means of HCHO concentrations were higher in summer,while enhanced amounts of NO_(2)were mainly observed in *** exhibited a hump-like seasonal variation,with higher monthly-averaged values not only occurred in warm months(July-August)but also in cold months(November-December).Peak values mainly occurred during noon for HCHO but emerged in the morning for CHOCHO and NO_(2),suggesting that HCHO is stronger link to photochemistry than *** further use the glyoxal to formaldehyde ratio(GFR)to investigate the VOC sources at different *** lowest GFR value is almost found in the altitude from 0.2 to 0.4 km,and then rises rapidly as the altitude *** GFR results indicate that the largest contributor of the precursor VOC is biogenic VOCs at lower altitudes,while at higher altitudes is anthropogenic *** findings provide a lot more insight into VOC sources at vertical direction,but more verification is recommended to be done in the future.

关键词： Formaldehyde Glyoxal MAX-DOAS Vertical distribution VOC