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Design and application of structural health monitoring system in long-span cable-membrane structure

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Earthquake Engineering and Engineering Vibration 2019年第2期18卷 461-474页

作者： Tang Teng Yang Dong-Hui Wang Lei zhang jian-ren Yi Ting-Hua School of Civil Engineering Changsha University of Technology Yueyang Sanhe Investment Management of Airport Construction Co.Ltd School of Civil Engineering Dalian University of Technology

Cable-membrane structures have small rigidity and are highly sensitive to wind. Structural health monitoring is necessary to ensure the serviceability and safety of the structure. In this research, the design method of a structural health monitoring system is using the characteristics of a cable-membrane structure. Taking the Yueyang Sanhe Airport Terminal as an example, a finite element model is established to determine the critical structural components. Next, the engineering requirements and the framework of the monitoring system are studied based on the results of numerical analysis. The specific implementation of the structural health monitoring is then carried out, which includes sensor selection, installation and wiring. The proposed framework is successfully applied to the monitoring system for the Yueyang Airport terminal building, and the synchronous acquisition of fiber Bragg grating and acceleration sensor signals is implemented in an innovative way. The successful implementation and operation of structural health monitoring will help to guarantee the safety of the cablemembrane structure during its service life.

关键词： cable-membrane structural health monitoring fi nite element model synchronous acquisition structural safety

Carbonaceous aerosols in PM_(10) and pollution gases in winter in Beijing

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Journal of Environmental Sciences 2007年第5期19卷 564-571页

作者： zhang ren-jian CAO Jun-ji LEE Shun-cheng SHEN Zhen-xing HO Kin-Fai Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences START Regional Center for Temperate East Asia Beijing 100029 China Institute of Earth Environment Chinese Academy of SciencesXi＇an 710075China Research Center for Urban Environmental Technology and Management Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China Department of Environmental Science and Technology Xi＇an Jiao Tong University Xi＇an 710049 China

An intensive observation of organic carbon （OC） and element carbon （EC） in PM10 and gaseous materials （SO2, CO, and O3,） was conducted continuously to assess the characteristics of wintertime carbonaceous aerosols in an urban area of Beijing, China. Results showed that the averaged total carbon （TC） and PM10 concentrations in observation period are 30.2±120.4 and 172.6±198.3 μ/m^3 respectively. Average OC concentration in nighttime （24.9±19.6 μ/m^3 was 40% higher than that in daytime （17.7±10.9 μ/m^3. Average EC concentrations in daytime （8.8±15.2 μ/m^3 was close to that in nighttime （8.9±15.1 μ/m^3. The OC/EC ratios in nighttime ranging from 2.4 to 2.7 are higher than that in daytime ranging from 1.9 to 2.0. The concentrations of OC, EC, PM10 were low with strong winds and high with weak winds. The OC and EC were well correlated with PM10, CO and SO2, which implies they have similar sources. OC and EC were not well correlated with O3. By considering variation of OC/EC ratios in daytime and night time, correlations between OC and O3, and meteorological condition, we speculated that OC and EC in Beijing PM10 were emitted as the primary particulate form. Emission of motor vehicle with low OC/EC ratio and coal combustion sources with high OC/EC ratio are probably the dominant sources for carbonaceous aerosols in Beijing in winter. A simple method was used to estimate the relative contribution of sources to carbonaceous aerosols in Beijing PM10. Motor vehicle source accounts for 80% and 68%, while coal combustion accounts for 20% and 32% in daytime and nighttime, respectively in Beijing. Averagely, the motor vehicle and coal combustion accounted for 74% and 26%, respectively, for carbonaceous aerosols during the observation period. It points to the motor vehicle is dominant emission for carbonaceous aerosols in Beijing PM10 in winter period, which should be paid attention to control high level of PM10 in Beijing effectively.

关键词： organic carbon elemental carbon diurnal variation PM10

Chemical Composition of Summertime PM_(2.5) and Its Relationship to Aerosol Optical Properties in Guangzhou,China

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Atmospheric and Oceanic Science Letters 2012年第2期5卷 88-94页

作者： Tao Jun Cheng Tian-Tao zhang ren-jian South China Institute of Environmental Sciences Guangzhou 510655 China Department of Environment Science and Engineering Fudan University Shanghai 200433 China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia (RCE-TEA) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Urban aerosols have a large effect on the deterioration of air quality and the degradation of atmospheric *** of the chemical composition of PM 2.5 and in situ measurements of the optical properties of aerosols were conducted in July 2008 at an urban site in Guangzhou,Southern *** mean PM 2.5 concentration for the entire period was 53.7±23.2 μg m *** mean PM 2.5 concentration (82.7±25.4 μg m 3) on hazy days was roughly two times higher than that on clear days (38.8±8.7 μg m 3).The total water-soluble ion species and the total average carbon accounted for 47.9%±4.3% and 35.2%±4.5%,respectively,of the major components of PM *** increase of secondary and carbonaceous aerosols,in particular ammonium sulfate,played an important role in the formation of haze *** mean absorption and scattering coefficients and the single scattering albedo over the whole period were 53±20 M m 1,226±111 M m 1,and 0.80±0.04,*** 2.5 had a high linear correlation with the aerosol extinction coefficient,elemental carbon (EC) was correlated with aerosol absorption,and organic carbon (OC) and SO 4 2 were tightly linked to aerosol scattering.

关键词： fine aerosol particle chemical composition aerosol optical coefficient

A Case Study of the Impacts of Dust Aerosols on Surface Atmospheric Variables and Energy Budgets in a Semi-Arid Region of China

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Atmospheric and Oceanic Science Letters 2010年第3期3卷 145-150页

作者： Ling Xiao-Lu Guo Wei-Dong zhang Lei zhang ren-jian Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China Key Laboratory of Regional Climate-Environment for East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Insititute for Climate and Global Change Research University School of Atmospheric Sciences Nanjing University Nanjing 210093 China

The authors present a case study investigating the impacts of dust aerosols on surface atmospheric variables and energy budgets in a semi-arid region of China. Enhanced observational meteorological data, radiative fluxes, near-surface heat fluxes, and concentrations of dust aerosols were collected from Tongyu station, one of the reference sites of the International Coordinated Energy and Water Cycle Observations Project (CEOP), during a typical dust storm event in June 2006. A comprehensive analysis of these data show that in this semi-arid area, higher wind velocities and a continuously reduced air pressure were identified during the dust storm period. Dust storm events are usually associated with low relative humidity weather conditions, which result in low latent heat flux values. Dust aerosols suspended in the air decrease the net radiation, mainly by reducing the direct solar radiation reaching the land surface. This reduction in net radiation results in a decrease in soil temperatures at a depth of 2 cm. The combination of increased air temperature and decreased soil temperature strengthens the energy exchange of the atmosphere-earth system, increasing the surface sensible heat flux. After the dust storm event, the atmosphere was dominated by higher pressures and was relatively wet and cold. Net radiation and latent heat flux show an evident increase, while the surface sensible heat flux shows a clear decrease.

关键词： case study dust aerosol energy budget semiarid region

The Role of Aerosol in Climate Change,the Environment,and Human Health

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Atmospheric and Oceanic Science Letters 2012年第2期5卷 156-161页

作者： zhang ren-jian Ho Kin-Fai Shen Zhen-Xing Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China School of Public Health and Primary Care Chinese University of Hong Kong Hong Kong China Department of Environmental Science and Engineering Xi’an Jiaotong University Xi'an 710049 China

Aerosol is an important component of the atmosphere,and its source,composition,distribution,and effects are highly *** and scientists have given much attention to aerosol problems,and it has become a hot topic due to the important role it plays in climate change and the Earth's *** this paper,1) the importance of aerosol in climate change,the atmospheric environment,and human health is summarized;2) the recent serious problems of aerosol pollution and the shortage of current aerosol research in China are pointed out;and 3) the necessity to enhance aerosol research in China is emphasized.

关键词： aerosol climate change environment humanhealth

Observations of Aerosol Optical Properties in the Beijing Urban Area in Summer

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Atmospheric and Oceanic Science Letters 2011年第6期4卷 338-343页

作者： JING Jun-Shan zhang ren-jian TAO Jun zhang Lei-Ming Key Laboratory of Regional Climate-Environment Research for Temperate East Asia （RCE-TEA） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China South China Institute of Environmental Sciences Ministry of Environmental Protection Guangzhou 510655 China Air Quality Research Division Science and Technology Branch Environment Canada. Toronto. Canad

To investigate aerosol optical properties in the Beijing metropolitan area, aerosol absorption coefficient （Ab）, scattering coefficient （So）, and fine particulate matter （PM2.5） were measured in the Beijing urban area from 20 May to 30 August 2009. The average Ab, So, single scat- tering albedo （SSA）, and PM2.5 concentration were 58.0±39.5 M m^-1, 343.5±353.7 M m 1, 0.80±0.10 and 63.6＋50.0 μg m^-3, respectively, during the observation period. Ab, Sc, and SSA all showed single peak diurnal variations, with their maximum values being measured at 0500, 1000, and 1300 local time, respectively. Ab and Sc had a strong positive correlation with PM2.5, and Ab, Sc, and PM25 all had positive correlations with relative humidity and negative correlations with wind speed.

关键词： optical properties fine particulate matter meteorological conditions

Elemental Composition of Atmospheric Particles in Winter at Datong City, Shanxi Province, China, and Its Impact on Beijing

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Atmospheric and Oceanic Science Letters 2009年第6期2卷 345-349页

作者： zhang ren-jian zhang Mei-Gen ZHU Ling-Yun HU Liang-Wen Key Laboratory of Regional Climate-Environment Research .for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Meteorological Science Institute of Shanxi Taiyuan 030002 China

Atmospheric particle samples were collected at an urban site of Datong, Shanxi Province, during December 2004 and their element concentrations at different sizes were analyzed by particle-induced X-ray emission (PIXE). Analysis of the observation data showed that particle pollution was heavy in winter at Datong and that concentrations of most elements were high in the coarse range. Factor analysis (FA) results indicated that the soil and dust, coal combustion dust, and industry dust are main sources for atmospheric particles in winter at Datong. The enrichment factors of element concentrations showed that particle pollution at Datong impacts the down-wind region-Beijing-in the dust season.

关键词： particles elemental concentration factor analysis

Transforming waste particles into valuable adsorbents via amyloid-mediated molecular engineering

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Science China Chemistry 2025年第1期68卷 317-328页

作者： Qingmin Yang jian Zhao Yujia zhang Xingyu Zhou Hao ren Bowen Hu Zhongli Lei Lixin Chen Peng Yang School of Material and Chemical Engineering Bengbu University Anhui Provincial Engineering Laboratory of Silicon-Based Materials School of Chemistry and Chemical Engineering Northwestern Polytechnical University Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education School of Chemistry and Chemical EngineeringShaanxi Normal University Xi'an Key Laboratory of Polymeric Soft Matter School of Chemistry and Chemical Engineering Shaanxi Normal University International Joint Research Center on Functional Fiber and Soft Smart Textile School of Chemistry and Chemical EngineeringShaanxi Normal University

The high-value utilization of industrial solid waste using a facile and eco-friendly process is of great interest and significance in reducing environmental pollution and developing a green circular economy. Herein, we propose an amyloid-mediated molecular engineering strategy to transform particulate waste into valuable adsorbents for metal ions. Our method has the advantage of aqueous solution fabrication under mild conditions without the use of high-temperature hydrothermal methods and toxic chemical reagents. Amyloid-mediated molecular engineering manipulates the phase transition of bovine serum albumin(BSA)on particulate waste surfaces, resulting in a remarkable ～3.1 times improvement in the adsorption capacity of fly ash, a typical industrial solid waste for gold ions after modification with the phase-transitioned BSA(PTB). The resultant adsorption ability was 69–1,980 times higher than those of conventional and emerging adsorbent materials such as ion exchange resins, activated carbon(AC), covalent organic frameworks(COFs), and metal-organic frameworks(MOFs). We further demonstrated the application of our PTB-modified materials in the recovery of precious metals from low-grade gold ore and electronic waste leachates. Consequently, this strategy could increase the value of waste materials nearly 27 times. In addition, this method is generally extendable to other conventional industrial adsorbents such as resin, clay, and Al2O3, and enhances their adsorption capabilities at least twofold. Overall, this work provides a simple and green approach for improving the adsorption performance of solid particles, and is expected to develop into a universal strategy for transforming waste particles into high-value-added products.

关键词： amyloid-like protein aggregates surface engineering fly ash solid waste adsorption

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混凝土斜拉桥施工阶段的体系可靠度

中国公路学报 2006年第5期19卷 53-58页

作者：刘扬张建仁长沙理工大学桥梁与结构工程学院

针对斜拉桥失效路径繁多的问题,采用改进的β约界法限制分枝规模,寻找并识别对结构体系可靠度起主导作用的主要失效模式。通过现场试验建立了高强度混凝土早龄期力学性能的经时概率模型。同时,考虑各主要失效模式间的相关性,提出了计算... 详细信息

针对斜拉桥失效路径繁多的问题,采用改进的β约界法限制分枝规模,寻找并识别对结构体系可靠度起主导作用的主要失效模式。通过现场试验建立了高强度混凝土早龄期力学性能的经时概率模型。同时,考虑各主要失效模式间的相关性,提出了计算体系失效概率上下界的实用方法。通过一座双塔斜拉桥施工期体系可靠度的计算实例表明了这一方法的有效性。研究成果对于评价混凝土斜拉桥施工期的结构整体性能和安全程度具有参考价值。

关键词：桥梁工程斜拉桥改进的β约界法体系可靠度施工期早龄期失效模式