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Influence of traffic on the temperature field of tunnel in cold region:A case study on the world’s longest highway spiral tunnel

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Underground Space 2023年第1期8卷 196-209页

作者： Yifan Jiang Jianyou Yu Ping Zhou Feicong Zhou Jiayong Lin Jinyi Li Ming Lin Feiya Lei Zhijie Wang Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengduSichuan 610031China School of Civil Engineering Southwest Jiaotong UniversityChengduSichuan 610031China Project Office of Yanchong Highway Zhang JiakouHebei 075000China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversitySichuan 611756China Infrastructure Operations Department of West China Hospital Sichuan UniversityChengduSichuan 610000China

The impact of the piston wind caused by vehicle traffic on the temperature field distribution of the tunnel cannot be ignored,especially in spiral tunnels,where the temperature field distribution is more complicated than that in straight *** on the world’s longest highway spiral tunnel,this study explores the influence of traffic on the temperature fields of spiral and straight tunnels,and proposes a new design method for laying length of insulation *** results show that traffic has a significant effect on the temperature field dis-tribution in the *** influence degree of different traffic elements decreases in the following order:average vehicle speed>daily traffic>morning rush hour>evening rush *** temperature field distribution of spiral tunnels is asymmetry on the left and right compared with straight tunnels,while the influence degree of traffic on the outside of spiral tunnels is similar to that of straight *** to the difference of wind direction and traffic direction at different tunnel openings,an asymmetric insulation layer laying method is *** is suggested that the lengths of the insulation layers of the Jinjiazhuang Tunnel should be 1200 m for the right tunnel inlet,700 m for the right tunnel outlet,700 m for the left tunnel inlet,and 1400 m for the left tunnel outlet.

关键词： Highway spiral tunnel Vehicle traffic cold region Temperature field Length of insulation layer

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Evolvement regularity of signal control parameters of urban road in cold region

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Journal of Harbin Institute of Technology(New Series) 2009年第6期16卷 873-878页

作者：蒋贤才苏小红 School of Transportation Science and Engineering Harbin Institute of Technology School of Computer Science and Technology Harbin Institute of Technology

In snow-icy road environment, the survey data indicate that the largest decrease in traffic flow running characters occurs when snow and ice begin to accumulate on the road surface. Saturation flow is decreased by 16% , speed is decreased by 30% , and start-up lost time is increased by 27%. Based on the signal control theory of HCM and Webster, the character values of traffic flow in different urban road environments were investigated, and the evolvement regularity of signal control parameters such as cycle, split, green time, offset, yellow time and red time in snow-icy road environment was analyzed. The impact factors and the changes in the scope of signal control parameters were achieved. Simulation results and practical application show that the signal control plan of road enviromnent without snow and ice will increase the vehicle delay, stop length and traffic congestion in snow-icy road environment. Thus, the traffic signal control system should address a suitable signal control plan based on different road environments.

关键词： evolvement regularity of signal control parameter traffic simulation cold region urban road

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Heavy metal contamination in soils of greenhouse vegetable production systems in a cold region of China

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International Journal of Agricultural and Biological Engineering 2019年第2期12卷 98-102页

作者： Pin Lv Zimin Wei Zhimin Yu Jizhou Zhang Limin Wang College of Life Science Northeast Agricultural UniversityHarbin 150030China Institute of Natural Resources and Ecology Heilongjiang Academy of SciencesHarbin 150040China

Heavy metal(HM)contamination in soils of greenhouse vegetable production(GVP)systems has drawn increasing attention in terms of food *** the present study,64 surface soils were sampled,and the concentrations of select HMs were determined using atomic absorption *** results showed that the concentrations of cadmium(Cd),lead(Pb),zinc(Zn),copper(Cu),nickel(Ni)and chromium(Cr)in the soils were(0.2±0.2)mg/kg,(26.5±8.4)mg/kg,(101.4±43.2)mg/kg,(29.1±8.6)mg/kg,(24.5±3.3)mg/kg,and(56.5±6.3)mg/kg,and the corresponding accumulation index(AI)values were 2.30,1.10,1.43,1.45,1.07,and 0.97,*** spatial distribution of the HMs suggested that Cd pollution displays a fractionation effect,which may be related to the source of Cd and its *** concentration of Zn was significantly correlated with that of other HMs,implying that a comprehensive interactive effect might occur between Zn and other ***,the values of the potential ecological risk index(RI)ranged from 41.23 to 185.91,meaning that attention should be paid to HM contamination of GVP soils to ensure food quality and safety.

关键词： heavy metal contamination cold region greenhouse vegetable production(GVP) distribution ecological risk food quality food safety

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Advances on bioremediation of oil-contaminated soil in cold region

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Acta Geochimica 2006年第S1期 96-97页

作者： Xiaoyan LIU1, Jingxin SUN1, Guocheng MAO2, Chunlei DAI1, Chun LI1, Qianya ZHU1, Yingli LI1 1 Geoscience College, Daqing Petroleum Institute, Daqing 163318, China 2 Security and Environment Protection Department, Daqing Petroleum Administrative Bureau, Daqing 163453, China

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Prevention and control measures of the major cold-region diseases (hypertension) in China

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Frigid Zone Medicine 2021年第1期1卷 3-8页

作者： Zhenwei Pan Yong Zhang Tengfei Pan Haihai Liang Baofeng Yang Department of Pharmacology(The Key Laboratory of Cardiovascular Research Ministry of Education)at College of PharmacyHarbin Medical UniversityHarbin 150086China Research Unit of Noninfectious Chronic Diseases in Frigid Zone Chinese Academy of Medical SciencesChina2019RU070

Hypertension is the most common cardiovascular condition in clinical practice and a major risk factor for stroke and cardiovascular *** are more than 270 million hypertension patients in China,and the prevalence of hypertension in the high-latitude cold areas is significantly higher than in the low-latitude warm *** unique epidemiological characteristics and risk factors of hypertension in the cold regions of China urge for establishment of the prevention and control system for targeted and more effective management of the condition.

关键词： hypertension cold region prevention cure

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Study on mechanism of circumferential cracks in cold-region tunnels

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Global Geology 2010年第2期13卷 75-78页

作者： ZHOU Lincong ZHENG Yifeng LI Zhong College of Construction Engineering Jilin University Changchun 130026 China

There exists frost damage in cold-region tunnels. The circumferential cracks affect the function of tunnels. Using three-dimensional finite element method, the authors analyzed the mechanism of circumferential cracks in cold-region tunnels It is proved that the internal thermal stress in lining exceeds the tensile strength of concrete, which is the direct cause for circumferential cracks occurring. The laws of thermal stress in lining induced by parameters such as temperature drop, horizontal drag coefficient and length of lining are analyzed. The conclusions are valuable to the design and construction of cold-region tunnels considering the thermal stress.

关键词： tunnel cold region circumferential crack temperature stress

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Strategies and Economic Benefit Analysis for Productive Landscape of Rape Flower Sea in cold regions

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Journal of Northeast Agricultural University(English Edition) 2024年第2期31卷 34-42页

作者： Zhang Jiaxin Wu Zhiheng Zhu Xuanbo Pan Shengkai Yan Yongqing College of Horticulture and Landscape Architecture Northeast Agricultural UniversityHarbin 150030China

The cold regions are located in high latitudes and cold *** local excellent ornamental plant resources are relatively *** plant species that are suitable for both ornamental and productive benefits of landscape of flower sea construction are also even ***,it is imperative to introduce and screen the plant resources suitable for cold regions to create the landscape of flower *** rape,an oilseed crop,was used as a research object in order to create a productive flower landscape with both ornamental and economic values in cold *** rape flower varieties,Qingza No.5,7,9,and 11,were introduced from Qinghai Hufeng Agricultural Science and Technology Group Co.,*** were planted in the experimental practice base of Northeast Agricultural University in three *** characteristics and seed yield of rape flowers on different sowing dates were *** fuzzy probability method was used to comprehensively evaluate the *** results showed that the rape flowers grew well in Harbin City during the experimental sowing period,which could form a good landscape of flower sea and had a considerable rapeseed *** could be widely used in cold urban and rural areas,such as Harbin *** view of the experimental results,the strategies of creating a productive landscape of rape flower sea were proposed and the economic benefits were *** could change the status quo of a uniform landscape of flower sea in cold regions,help the development of rural tourism,and promote local economic income.

关键词： rape flower sea productive landscape cold region landscape construction economic benefit

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Dynamic response characteristics of a circular lined tunnel under anisotropy frost heave of overlying soil at the tunnel portal section in cold regions

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Journal of Mountain Science 2023年第5期20卷 1424-1440页

作者： ZHANG Shuo-cheng CHEN Wen-hua School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China

The rapid development of traffic engineering in cold regions and its consequent problems need to be *** this paper,the dynamic response characteristics of the tunnel portal section in cold regions with harmonic load acting on the lining were studied in the frequency *** lining is in close contact with the frozen soil,and there is relative movement between the frozen and unfrozen soil due to the phase *** analytical solution of the vibration of tunnel portal section caused by the harmonic load acting on the lining was derived under the consideration of the anisotropy frost heave of overlying *** on the continuity conditions and boundary conditions,the undetermined coefficients were obtained,and the analytical solutions for different medium displacements and stresses of the cold-region tunnel system were *** vertical pressure coefficient was equivalently simplified as a variable that could be used to replace the thickness of the overlying soil above the *** analysis of the parameter model shows that the change of the medium parameters(lining,frozen,and unfrozen soil)affects the circumferential stresses,the radial displacements and their peak frequencies of the *** example,the increase of density ratio of tunnel lining to frozen soil decreases the radial stresses of the frozen and unfrozen soil;the increase of volumetric frost heaving strain of the frozen soil increases the radial displacements of the frozen surface and decreases the stability of the frozen surface;the increasing of thickness of the frozen soil significantly reduces the radial displacement of unfrozen soil at dimensionless radius η=4.5 compared with that of frozen soil at η=1.5.

关键词： Frost heave Tunnel portal section Relative movement Dynamic response characteristics cold region

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Numerical simulation investigation on hydration heat temperature and early cracking risk of concrete box girder in cold regions

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第4期10卷 697-720页

作者： Shi Han Yongjian Liu Yi Lyu Jiang Liu Ning Zhang School of Highway Chang'an UniversityXian 710064China Qinghai Transportation Engineering Technical Service Center Xining 810008China School of Civil Engineering Chongqing UniversityChongqing 400045China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China

The temperature change caused by hydration leads to early-age cracking in concrete box *** early-age cracking risk is further improved with low air temperature and large daily temperature difference,especially in Northwest *** fill this gap,a temperature experiment and numerical simulation were performed on an actual concrete box girder segment in Northwest *** temperature field,thermal stress and cracking risk were analyzed using evolution curves,distribution curves and *** key parameters that influence the hydration heat temperature,including the cement hydration heat release,cement content,height-width ratio of web,initial temperature,convective coefficient of top plate surface,were *** anti-cracking case based on parameters analysis was put *** results indicated that the temperature evolution can be divided into three stages:warming,cooling and environment significantly *** the thickness of each plate,temperature distributed is single peak in the *** the width or height,temperature distributed is double peaks at axillary position for the top and bottom plates,and single peak in center for the *** axillary position and web have high thermal stress and significant cracking *** temperature difference of each plate,and the early-age cracking risk can be reduced by effectively adjusting the key *** these,the former two parameters are the most significant *** maximum cracking risk can be decreased by 15.7%for every 50 kJ/kg hydration heat *** maximum cracking risk can be decreased by 13.1%for every 50 kg/m^(3)cement content reduction.

关键词： Bridge engineering Concrete boxgirder Hydration heat cold region Temperature action Thermal stress

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Correlation analysis of longitudinal cracks and vertical deformation within asphalt pavement of cold regions

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Research in cold and Arid regions 2023年第6期15卷 278-287页

作者： Ke Chen Lun Ji ZeYu Xiao JinQi Wu LinLin Xu ZhiCe Cheng Heilongjiang Provincial Highway Survey and Design Institute HarbinHeilongjiang 150080China School of Traffic Science and Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150090China Heilongjiang Highway Construction Center HarbinHeilongjiang 150090China

The asphalt pavement longitudinal crack is a common distress in cold regions,resulting from uneven deformation of the *** of the correlation law between uneven deformation and crack distress is of positive significance for understanding the mechanism of crack initiation,and putting forward treatment *** view of the complexity of longitudinal crack inducement and road surface deformation,the grey relational method was used to analyze this *** long-term monitoring of the vertical deformation data of typical road sections,the vertical deformation law of the pavement surface and its deformation characteristics under the action of temperature field are *** such as vertical relative deformation,vertical relative deformation rate and vertical differential deformation VDSr were constructed to describe vertical deformation *** distribution characteristics of longitudinal fractures and their length and distribution characteristics are also *** grey correlation analysis theory was utilized to analyze the relationship between deformation characteristics of sections,cross sections and monitoring points and longitudinal crack characteristics(length and location).The analysis reveals a linear positive correlation or a high correlation between several *** study can provide a deeper understanding of the occurrence and development mechanism of longitudinal cracks in asphalt pavement of cold areas,and give references for the research of road engineering structure,materials and distress prevention.

关键词： Asphalt pavement cold region Longitudinal crack Vertical deformation Grey relational analysis

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