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25 April 2016, Volume 35 Issue 2 Previous Issue    Next Issue
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Bridge & Tunnel Engineering
Highway & Railway Engineering
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Bridge & Tunnel Engineering

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Analysis of Cable Parametric Vibration Model and Response with Consideration of Temperature Effect WANG Feng, Chen Fuqing, WEN Xiaoxu,PENG Zhang 2016, 35(2): 1-5.  DOI: 10.3969/j.issn.1674-0696.2016.02.01 Abstract ( )   PDF (2114KB) ( )   The vibration of super-long cable under joint effect of non-uniform temperature field and deck excitation was analyzed.A model of cable parametric vibration under the joint effect of gradient temperature field and deck excitation was set up by considering the impacts of cable nonlinearity and atmospheric gradient temperature field and taking force of temperature field as the boundary of cable vibration. Based on Galerkin method, the main parametric vibration equation within cable plane was developed and the equation of cable amplitude-frequency response under joint excitation of temperature and deck was obtained by means of multi-scale method. Program for numerical computation was prepared and the law of influences on their parametric vibrations imposed by gradient temperature field, detuning value and deck excitation amplitude was analyzed and explored. The results show that the cable vibration in gradient temperature field is of apparent hard spring nature. With the increased detuning the amplitude-frequency response curve gradually changed to straight angle and multiple-responses were caused. The cable vibration in the temperature field bears feature of “patting”. With the increase of temperature the cable parametric resonance area gradually expanded. The cable vibration amplitude under joint excitation of temperature and deck is lower than that of single cable plane. With the increased deck excitation amplitude, both the cable resonance area and vibration value increased notably. However, the resonance area and vibration amplitude decrease with increased damping. References | Related Articles | Metrics

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Application of Multistage Crossing Genetic Algorithms by Optimal Sensor Placement in Dynamic Test of Continuous Rigid Frame Bridge LIU Laijun,NI Futao,SUN Weigang,SHAO Yongjun,LI Xiao 2016, 35(2): 6-8.  DOI: 10.3969/j.issn.1674-0696.2016.02.02 Abstract ( )   PDF (2017KB) ( )   The improvement of genetic algorithm method based on optimal arrangement of sensor in dynamic test. was elaborated.The proposed improved method by using multistage crossing instead of two-point crossing improved the code of crossing in traditional genetic algorithm and was applied in the dynamic test of some continuous rigid frame bridge. Through calculation and comparative analysis, it is discovered that the application of multistage crossing method can effectively prevent the happenings of premature convergence and local optimal solution and better utilize the variety of initial population. Hence, the results by multistage crossing method are more superior to that of traditional generic algorithms. References | Related Articles | Metrics

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Anchorage Displacement Monitoring System Based on Laser and Image Analysis LAN Zhangli ,YAO Jinqiang ,ZHANG Hong ,TIAN Yuan ,LAN Tianfeng  2016, 35(2): 9-12.  DOI: 10.3969/j.issn.1674-0696.2016.02.03 Abstract ( )   PDF (2031KB) ( )   A new system was developed for monitoring displacement of anchorage structure based on image processing technology and laser projection displacement sensing technology for purpose of monitoring the stress and damage suffered by the tunnel-type anchorage structure in the complex water erosion condition after the inundation of Three Gorges reservoir. Firstly, the relationship between the spatial point and the plane point was established by pixel calibration. Secondly, the displacement of anchorage was calculated by use of the practical improved method based on dynamic gradient spot center positioning algorithm. Thirdly, the experimental results have proved the high accuracy and stability of the system which satisfies the required performance for long-term online displacement monitoring of anchorage structure. Finally, in order to broaden the application of the system in safety monitoring for large structures in earlier time, some errors in the experiment are analyzed and the countermeasures against such errors are provided. References | Related Articles | Metrics

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FEM Study on the Stress Concentration Factors at Weld Toe of Butt-Welded Joints for High Strength Steel JIANG Yong, QIAN Ji, CHEN Weizhen 2016, 35(2): 13-16.  DOI: 10.3969/j.issn.1674-0696.2016.02.04 Abstract ( )   PDF (2218KB) ( )   The stress concentration factor (SCF) is one of the most important factors to evaluate the safety of structures. According to the thereto-effect of welding process, the nonlinear changes of material properties were considered, the residual stress distribution was analyzed and compared with the experimental results. Furthermore, different weld geometric parameters were considered and the effects of them on SCFs were discussed. Research indicated: The influence of residual stress on stress concentration effect is evident when low stress is applied for RQT701 high-strength steel. And it is possible to decrease the stress concentration factor of butt-welded joint by decreasing weld bead flank angle or/and increasing the weld toe radius,and the SCFs increase with the augment of plate thickness. References | Related Articles | Metrics

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Finite Element Analysis of Ship Collision Force of Wanzhou Yangtze River Bridge WEN Chuanyong 2016, 35(2): 17-20.  DOI: 10.3969/j.issn.1674-0696.2016.02.05 Abstract ( )   PDF (2041KB) ( )   With the rising of water level at Three Gorges Reservoir Region, the arch ring of Wanzhou Yangtze River Bridge is in danger of ship impact. Based on the shipping condition of Wanzhou reach of Yangtze River, an analytical study on the ship impact on the piers and arch ring of the bridge was conducted by means of setting up spatial finite element model on five different types of ships. The result shows that 5 000 t ships exert the greater impact on the bridge piers and the arch ring for longer acting time with greater impact on the piers. The ultimate lateral resistance capacities of the piers and arch ring are respectively 2 000 t and 350 t.When the water level reaches 175 m in the reservoir area, the affordable ultimate ship impact on the arch ring and piers are respectively 1 094 t and 115 t. References | Related Articles | Metrics

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Analysis on Displacement of Surrounding Rock in Tunnel with Consideration of Interval Influencing Factors  HUANG Mingkui,QUAN Jian 2016, 35(2): 21-23.  DOI: 10.3969/j.issn.1674-0696.2016.02.06 Abstract ( )   PDF (1796KB) ( )   Surrounding rock displacement was one of the important parameters to assess rock stability in tunnel and the uncertainty of these parameters was seldom considered in the conventional calculation of surrounding rock displacement. Because of the uncertainty of parameters that influence the surrounding rock displacement, a new displacement calculating model suitable for the interval analysis was built by combining the conventional displacement calculating model with the interval analysis method, and then the model was applied to analyze the interval distribution features of arch crown displacement of surrounding rock condition of rating IV. The analysis result shows that the model can objectively reflect the actual deformation behavior of rock due to displacement and the research results can be taken as the reference for determination on subsequent works design, execution and the time for supporting .  References | Related Articles | Metrics

Highway & Railway Engineering

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Progress of Study on Sulfate Attack on Concrete Materials CHEN Da,YU Xiaotong,LIAO Yingdi,WANG Qinfen,WANG Xiao 2016, 35(2): 24-30.  DOI: 10.3969/j.issn.1674-0696.2016.02.07 Abstract ( )   PDF (1030KB) ( )   Sulfate attack is one of the key factors to degrade the property of concrete materials.The experimental researches on the influence of sulfate attack onproperties of concrete materials were reviewed in ths paper.The concentration of SO2-4, types of anions pH values,temperature and dry-wet cycles in the surroundings have significant effect on the sulfate attack on the concrete materials.The water cement types and admixture influence the compactness of conxrete, the contents of C -S-H and Ca(OH)2,affecting the resistance of concrete to sulfate attack in another way. Furthermore , the tension and compression stress, other loads in the environment have effect on the evolution of properties of concrete under sulfate attack. Also,the statistical models and mechanical constitutive models were induced in this study and proved a new research direction for the life predication of the concrete structure under the condition of sulfate. References | Related Articles | Metrics

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Experimental Study on Dynamic Strain of Asphalt Surface Course of Rigid-flexible Composite Pavement Structure LIU Zhisheng，ZHAO Juanjuan  2016, 35(2): 31-34.  DOI: 10.3969/j.issn.1674-0696.2016.02.08 Abstract ( )   PDF (1888KB) ( )   For further research into rut disease mechanism of asphalt surface course of rigid-flexible composite pavement, wheel rutting test was used to simulate dynamic load on pavement. The dynamic strain of asphalt mixture of different types under different temperature, under different loads in sizes and directions were measured by use of optical fiber testing technology to analyze the characters of wheel rutting deformation of asphalt surface course in composite pavement from the three aspects of load size, mixture types and the temperature. The result showed that under dynamic loading, the cross strain of the asphalt surface course of the rigid-flexible composite pavement is less than the longitudinal strain. After removal of load, the cross strain can recover by 60% while the longitudinal strain can recover only by 20%. Within given range there exists a positive linear relationship between the dynamic strain of asphalt mixture and load size while a reverse directional linear relationship between strain recovering ability and load size. SMA is of 12% less dynamic strain than AC and of 60% higher recovering ability. In the surroundings of high temperarture, indirect loading may also cause strain of asphalt mixture and SMA has a notably higher resistance against deformation than AC. References | Related Articles | Metrics

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Analysis of the Properties of Asphalt Mortar Affected by DCLR Content and Filler-Asphalt Ratio JI Jie,LI Pengfei,SUO Zhi,SHI Yuefeng,XU Ying ,XU Shifa， 2016, 35(2): 35-39.  DOI: 10.3969/j.issn.1674-0696.2016.02.09 Abstract ( )   PDF (1936KB) ( )   To analyze the properties of asphalt mortar affected by DCLR content and filler-asphalt ratio, the asphalt mortars with different DCLR content and filler-asphalt ratio were prepared. The “two factors and four levels” orthogonal experiment was conducted. The G*/sinδ, G*·sinδ, m-value and S of asphalt mortar affected by DCLR content and filler-asphalt ratio were evaluated by using DSR and BBR. The results show that DCLR content and filler-asphalt ratio exert significant effect on the properties of asphalt mortar. The high-temperature property of asphalt mortar is improved constantly but the fatigue resistance and low-temperature property of asphalt mortar gradually decreased with the increase of DCLR content and filler-asphalt ratio. It is discovered that compared with filler-asphalt, the addition of DCKR exerted far greater influence on asphalt mortar.In view of overall property changes of asphalt mortar, the asphalt demonstrated best property when DCLR content is lower than 10% and filler-asphalt ratio less than 1.0.  References | Related Articles | Metrics

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Study of Water Stability of Different Asphalt Mixtures for Ultra-Thin Surfacing Layer SU Zhonggao 2016, 35(2): 40-44.  DOI: 10.3969/j.issn.1674-0696.2016.02.10 Abstract ( )   PDF (984KB) ( )   By performing immersion rutting test and freeze-thaw splitting test, the water stability of nine different asphalt mixtures for ultra-thin surfacing layer was studied. The said nine asphalt mixtures were made respectively by three gradations (namely Type-B with USA gradation, improved SMA-10 and OGFC-10) and with three binders (namely SBS modified asphalt, common asphalt + 8% anti-rutting agent and highly viscoelastic asphalt). The test results show that five types of asphalt mixture for ultra-thin surfacing layer (namely Type-B SBS modified asphalt mixture, improved SMA-10 SBS modified asphalt mixture , Type-B highly viscoelastic asphalt mixture, improved SMA-10 highly viscoelastic asphalt mixture and OGFC-10 highly viscoelastic asphalt mixture ) meet China’s prevailing specification for water stability of asphalt mixtures.Among them the improved SMA-10 highly viscoelastic asphalt mixture demonstrated optimal general performance with both rut dynamic stability and the immersion rutting dynamic stability 2.0~4.5 times and 2.0~4.7 times that of other eight mixtures and is thus recommended for use in pavement protective maintenance or repair of key urban artery, expressway or road of heavy traffic. References | Related Articles | Metrics

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Research of the Influential Factors of Asphalt Mixture Permittivity WANG Zijing 2016, 35(2): 45-49.  DOI: 10.3969/j.issn.1674-0696.2016.02.11 Abstract ( )   PDF (1390KB) ( )   To assess the impact of factors affecting the dielectric constant of asphalt concrete, we studied the inhomogeneous composition of asphalt concrete material dielectric properties, considering the impact on the dielectric constant of bitumen content, unit weight and moisture content. The results show that at the same porosity range, asphalt concrete specimens dielectric constant decreases with increase of asphalt content；asphalt concrete specimen’s dielectric constant can be calculated by the mixed theoretical model；asphalt concrete density can be predicted by dielectric constant,porosity and asphalt content. References | Related Articles | Metrics

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Dynamic Simulation Analysis on Vibration Compaction System of Pavement HUANG Zhifu, LIANG Naixing, ZHAO Yi, FAN Wensheng, FAN Youwei 2016, 35(2): 50-53.  DOI: 10.3969/j.issn.1674-0696.2016.02.12 Abstract ( )   PDF (2117KB) ( )   A dynamic model of pavement vibratory compaction system was established based on the relationship between the vertical acceleration of vibratory roller and pavement compactness. The results of simulation by Simulink show that if the vibratory roller is in reasonable conditions within the scope of work and on the basis of the constant exciting force and vibrating frequency, the accelerating speed of roller wheel increases with increased stiffness coefficient of pavement material and decreases with the increased damping coefficient. The three-dimensional vibratory-pavement simulating model was established with finite element analysis software ABAQUS to simulate the pavement vibratory compaction system. Analysis results show that if pavement materials permit, use of strong vibration and first gear speed generates optimum compaction result. With the increased rounds of compaction, the pavement material density is improved. During re-compacting and final compacting the higher speed of vibratory roller should be applied and second gear of driving speed can be applied in compacting to improve production efficiency and reduce works cost.  References | Related Articles | Metrics

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Study on the Optimum Design Method for Vertical Pre-Stressed Anchor Anti-Slide Piles with Trapezoid Section CHEN Hongkai, ZHAO Chunhong 2016, 35(2): 54-59.  DOI: 10.3969/j.issn.1674-0696.2016.02.13 Abstract ( )   PDF (2018KB) ( )   By fusing advantages between cantilevered anti-slide piles and pre-stressed anchor anti-slide piles, a new method for landslide control, the vertical pre-stressed anchor anti-slide piles with trapezoid section, was proposed. By analyzing loaded performance of the vertical pre-stressed anchor anti-slide piles with trapezoid section, the calculation method for its internal force was established, and the optimum formula for the design value of pre-stressed anchor tension, which was related to design parameters, such as, landslide thrust and pile distance, was gained. Engineering examples indicated that, within same cross-sectional area, by comparing with cantilevered anti-slide piles with rectangle section, the vertical pre-stressed anchor anti-slide piles with trapezoid section could increase the compression zone of anti-slide piles by 25.8 percent and decrease the reinforcement amount in tensile area by 20.4 percent. It has a good economic performance. The method provides a new technological selection for the management of large and oversize scale landslide in the river and reservoir slope and/or landslides with thick colluvium and slope sediments along highway. References | Related Articles | Metrics

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Technical Design of Embankment Subsidence Monitoring of High-speed Railway in Operation and Maintenance ZHOU Jinguo, CUI Shuzhen, ZHU Chengfei 2016, 35(2): 60-63.  DOI: 10.3969/j.issn.1674-0696.2016.02.14 Abstract ( )   PDF (1454KB) ( )   An embankment settlement monitoring technical scheme was developed for purpose of embankment settlement monitoring in operation and maintenance of express railway based on the features of high flatness of high-speed railway and routine maintenance and regulation works below embankment line. Monitoring sections were arranged and stable points CPIII on bridge were selected as reference points for embankment settlement monitoring and the observational method was used by taking CPIII points in monitored route as turning points. This technical scheme solves the problems of difficult fixation of monitoring points in surface settlement zone and tight schedule for maintenance and monitoring works and its application in embankment settlement monitoring during maintenance and operation stages generated positive results and meet technical requirement for third-level deformation measuring of high-speed railway. References | Related Articles | Metrics

Port & Waterway · Hydraulic & Hydroelectric · Resources & Environment

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Sediment Numerical Simulation of Changshou to Luoqi Reach in Fluctuating Backwater Area of Three Gorges Project BI Fangquan 2016, 35(2): 64-69.  DOI: 10.3969/j.issn.1674-0696.2016.02.15 Abstract ( )   PDF (2214KB) ( )   The accumulated siltation and sediment in Three Gorges reservoir zone caused new problem to the daily management, maintenance and regulation of waterway. In this paper, the 2D flow-sediment mathematical model was established to simulate the muddy sand transport in the Three Gorges Reservoir regional backwater variation zone in the river reach from Changshou to Luoqi. Sensitivity analysis shows that sediment input factor is key parameter influencing sedimentation volume. Water level, flow velocity and direction and topography verifications show that this mathematical model calculation results well reflect the reality hydrology and siltation. The calculation results show that subject to the influence of backwater of the Three Gorges Reservoir, cumulative deposition happens in the reach from Changshou to Luoqi and siltation zones are located primarily in the river sinuses，the backflow zones and broad-shallow reaches of the river and siltation mainly occurred in deep trench and side beach in flooding season from June to September. Because of the siltation and sediment, water depth at upper and lower reaches of Luoqi and Wangjiatan is insufficient so as to impede navigation. It is suggested to enhance monitoring and take timely rectification and regulating measures. References | Related Articles | Metrics

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Numerical Model of Channel Regulation for Bazinao Shoal Group NI Zhihui ，GUO Yi，WU Lichun 2016, 35(2): 70-74.  DOI: 10.3969/j.issn.1674-0696.2016.02.16 Abstract ( )   PDF (2163KB) ( )   Jialing River Bazinao group shoal section is located in the tail of Fengyi navigation power junction reservoir. Due to the separation of the water discharge outlet of Mahui power station and vessel lock exit, the right branch of Bazinaotan is of narrow channel of shallow water and the left branch is extremely curved and narrow, which can not accommodate navigation. Further in Dashi shoal section the sand-pebble bar in water splits Jialing river into two branches right and left of which the left branch is relatively straight but is of insufficient water depth in dry season while the right branch is of smaller curve radius and does not meet requirement for high class channel construction. Aiming at these navigation impeding characteristic problems of Bazinaotan shoal group reach of Jialing river, a mathematical model was set up to calculate, analyze and compare the two different treatment schemes for current and sediment conditions. The results show that this mathematical model can well simulate reach flow and sediment accumulation situation. As to the end result of regulation and rectification, scheme one is superior for such advantages of less siltation, more stable channel and thus can be taken as implementation scheme for reference of design. References | Related Articles | Metrics

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Three-Dimensional Finite Element Analysis on Stress Path for Core Rock-Fill Dam ZHU Jungao , SUN Pengfei ,CHU Fuyong 2016, 35(2): 75-79.  DOI: 10.3969/j.issn.1674-0696.2016.02.17 Abstract ( )   PDF (2259KB) ( )   Three-dimensional finite element stress and strain analysis was conducted for the core rock fill dam founded on deep covering layer and the change of stress path of rock fill dam and foundation during dam construction and inundation period were studied. The results are concluded as follows: in both dam construction and inundation periods, the stress path within dam body and foundation can be approximated to linear changes. The two ratios basically remain constant namely the increment ratio between major and minor principal stresses and the increment ratio between partial and spherical stresses and they varied with dam filling building period and inundation period. The magnitude of ratio changed with position and surrounding of materials placed. These research results provide the basis for relevant tests of earth dam and facilitates the establishment of constitutive model for further study of stress deformation of core rock-fill dam.  References | Related Articles | Metrics

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Research and Design of Centrifuge Model Tests on Lateral Mechanics Properties of Composite Foundation LI Lianxiang, FU Qinghong, ZHANG Haiping, HU Xuebo 2016, 35(2): 80-88.  DOI: 10.3969/j.issn.1674-0696.2016.02.18 Abstract ( )   PDF (1878KB) ( )   The centrifuge model tests on lateral mechanics properties of composite foundation were designed, some feasible solutions to these key complex technological problems in the tests were achieved including preparation of the composite foundation models, fabrication of the simulating structures, arrangement of data acquisition system, application of the surcharge load on pit edge and development of excavation method. In addition, numerical software PLAXIS 3D was used to simulate all loading cases of tests. So expected results were achieved by which we can generally master ground deformation under all loading cases, supporting and CFG pile deformation under forces and retained soil pressure distribution and variation law. It is preliminarily assumed that both the horizontal deformation and its scope of CFG piles decrease with the increasing distance from the edges of the pit and the settlement at CFG piles is far smaller than the of the soil between piles. It is considered that the CFG piles have stuck in cushion. The surcharge load on pit edge can make CFG piles more effective in aspects of consolidating soil, reinforcing the retaining structure and controlling their own deformation.  References | Related Articles | Metrics

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Non-Cohesive Particles Starting Mechanism Under the Changing Seepage Direction LIANG Yue, ZHANG Qiang, ZENG Chao, LIU Zeyu, 2016, 35(2): 89-92.  DOI: 10.3969/j.issn.1674-0696.2016.02.19 Abstract ( )   PDF (1995KB) ( )   Through varying angle model slots designed by self a series of non-cohesive particles starting tests were researched. The hydraulic gradient flow velocity and particle size were studied under the different angle between the seepage direction and the horizontal direction. Results show that the incipient velocity and hydraulic gradient of gravel particles increases as the angle between the seepage direction and the horizontal direction. Particles permeating the gap scouring becomes more difficulty.At the same time the incipient velocity and hydraulic gradient of gravel particles increases as the particle size when the angle keeps constant.With the particles being carried out, integral structure of the test sample is affected,it accelerates the seepage velocity and forms seepage channels which the average width narrow from downstream to upstream. References | Related Articles | Metrics

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Characteristic Analysis of Climatic Elements Change in Heilongjiang Province HAO Zhenchun,SONG Junbo,XING Ruofei,LIU Wenbin 2016, 35(2): 93-99.  DOI: 10.3969/j.issn.1674-0696.2016.02.20 Abstract ( )   PDF (2085KB) ( )   Based on the 9 meteorological elements of data and statistics taken from 30 meteorological stations between 1972 to 2012 in Heilongjiang province, the decadal meteorological elements and seasonal changes of precipitation and snow and further reveals the law of such changes were analysed. Meteorological trend rate and Mann-Kendall test were used to test the element tendency and analyze meteorological elements changing tendency and prominence. Then the mean values of meteorological elements for years from stations were treated by reverse distance weighted mean method and interpolation and contour map indicating its spatial distribution was obtained to analyze the climatic element changes in different regions. The results show that Heilongjiang experiences obvious climatic changes which vary subject to different regions and different years. The mean temperature of majority regions rises and the difference between lowest temperature and highest temperature is reducing year by year and their spatial distribution is closely related to altitude. Snow amount and precipitation increases variably year by year and precipitation decreases from central region to bilateral regions as to spatial distribution. The data from majority stations show decreased mean wind speed, relative humidify and daily sunlight hours and small-scaled evaporation. Spatial distribution differs due to different specific locations of stations. References | Related Articles | Metrics

Traffic & Transportation Engineering

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Analysis of Impact of Parking Construction Scale on Road Capacity TANG Boming，WANG Weijun，LIU Tangzhi，ZENG Chao 2016, 35(2): 100-104.  DOI: 10.3969/j.issn.1674-0696.2016.02.21 Abstract ( )   PDF (1294KB) ( )   It is analyzed from the size and nature of the parking lot, with the actual statistical laws of the different nature of the parking lot and out of traffic, to establish the model of in and out of rush hour traffic. Then according to traffic flow theory, analyzing the influence of in and out of traffic under the two forms of organization of parking lot, and calculating the relationship between its size and road capacity after the parking lot constructed. Finally, the use of simulation software VISSIM to do a visual simulation analysis and simulation statistics of two entrances traffic organization form ,which verifies the correlation between the size of parking lot and road capacity. The result shows that parking siting, construction scale and entrances traffic organization must consider the impact on road capacity to ensure smooth traffic of city roads. References | Related Articles | Metrics

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Research on Connectivity Reliability of OD in Urban Road Network Based on Floating Car Data HU Jihua , YANG Yuanyuan , CHENG Zhifeng , LIANG Jiaxian , 2016, 35(2): 105-109.  DOI: 10.3969/j.issn.1674-0696.2016.02.22 Abstract ( )   PDF (1138KB) ( )   A road connectivity reliability model based vehicular speed of the road section was established. In this model, the connectivity of a given road section was indicated by the ratio of freedom loss of vehicle on given road section in real scenario in relation to that of free running scenario. Connectivity was expanded from the 0,1 binary value judgment to the interval ［0, 1］. By taking Guangzhou city as an example, the model was applied to analyze the changes of the connectivity reliability of the road sections based on the floating car data (FCD) of taxi GPS. A conclusion is drawn that the percentage of the sections of good connectivity reliability in the afternoon is about 10%~35% lower than those in other periods, and drops to 51.2%, the lowest in the evening peak.  References | Related Articles | Metrics

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Study of the Traffic Network Efficiency Based on Individual Traveler’s Behavior SUN Qiuxia, SUN Lu,LIU Xinmin 2016, 35(2): 110-113.  DOI: 10.3969/j.issn.1674-0696.2016.02.23 Abstract ( )   PDF (2098KB) ( )   The impact of the individual traveler’s micro behavior on the macro characteristics of the transportation network. was discassed. The traveller types and their route selection rule were redesigned according to different traffic information received by them. The impact rate of individual traveller’s action on traffic network efficiency was simulated by considering traffic network evaluation model including such factors as need for transport, time and cost .The simulation results show: the timely supply of traffic information and traveller’s learning ability of traffic information can overall improve the running efficiency of road network. Of similar travelling scale, the traveller with learning behavior causes minor influence to the traffic network efficiency which is stable. In case of sufficient traffic information supplied, the number of information learned travellers is influenced by the capacity of road network. References | Related Articles | Metrics

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A Model Study on Multiple Transport Service Decision Based on Travelers’ Profits SHEN Li，ZHANG Tong，QIU Huiyang 2016, 35(2): 114-119.  DOI: 10.3969/j.issn.1674-0696.2016.02.24 Abstract ( )   PDF (1025KB) ( )   Considering the synergic competition that private cars and surface public transit means share the travelling passengers in peak time of ubran traffic artery, a traveller’s subjective trip preferable choice and the objective effect of trip mode were introduced and a transport service decision model based on traveller’s maximum total benefits was established. By simulating and calculating the outward motorcar moving on Chengdu Tianfu Avenue, the optimal road traffic allocation structure was obtained to meet different demands and achieve maximum traveller’s benefits and the feasibility of this model was thus verified. By application of this model , the travel’s trip mode choice can be influenced to promote the balance of between private car and public bus in respect of occupying motorway of urban artery and realize the traveller’s mixum profits. So this model can provide some valuable suggestions to road managers and mass transit operater in traffic flow control, decision-making and ticket pricing. References | Related Articles | Metrics

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Analysis of Travel Behavior and Its Elasticity for Migrant Workers CHEN Hong，GAN Zuoxian，HE Yuting，FENG Hui 2016, 35(2): 120-125.  DOI: 10.3969/j.issn.1674-0696.2016.02.25 Abstract ( )   PDF (1053KB) ( )   To study migrant workers’ travel behavior, multinomial logit models of travel chain choice and travel mode choice were established by taking seven factors as characteristic variables including gender, age, family members, travel distance etc. and travel chain and travel mode as decision variables. The models were calibrated and tested with 244 as sample data on migrant workers’travel behavior in Xi’an. Thus, choice probability models were fitted out and the influence of various characteristic variables impacting the choice models were analyzed. Finally, by introducing the concept of elasticity, the elasticity of the travel behavior for migrant workers was analyzed. The result shows that the travel chain choice and travel mode choice of migrant workers are both lack of elasticity, and their travel behavior is of single-mode. References | Related Articles | Metrics

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An Optimization Model and Algorithm for School Bus Routing HAO Zhongna 2016, 35(2): 126-130.  DOI: 10.3969/j.issn.1674-0696.2016.02.26 Abstract ( )   PDF (1893KB) ( )   To facilitate selection of school bus stations, allocating student groups to stations and developing vehicle routings, the mathematical programming model was established to minimize the cost of the vehicle travel time, the students journey time, and the students walking time to the station by considering the key constraint conditions such as the longest riding time in the school bus and the longest walking time of students to the station. Then the improved genetic algorithm was put forward to for above purpose and by this algorithm, the excellent individual of initial population was produced by heuristic method, and the operators with heuristic knowledge were designed to improve the excellent searching efficiency. The example analysis results show that the proposed method is feasible with significant results, which can effectively provide optimal route for school bus of large number. References | Related Articles | Metrics

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Passenger Satisfaction Evaluation of Urban Rail Transit Based on Comprehensive Weight PENG Jinshuan, HE Jianwei, SHAO Yiming, CHEN Jian 2016, 35(2): 131-136.  DOI: 10.3969/j.issn.1674-0696.2016.02.27 Abstract ( )   PDF (1969KB) ( )   To avoid the defect of over-subjective evaluation by tradition method, a new method evaluating passenger satisfaction of urban rail transit was raised based on AHP-entropy weight. An index system for evaluating rail passenger satisfaction was established by considering such items as transport efficiency, convenience, comfort, security, neatness and service level. With the comprehensive weight determined by analytic hierarchy process and entropy weight methods and in combination with the improved fuzzy mathematical method, passenger satisfaction evaluation was conducted subsequently. The working efficiency of the model was then verified by case study of Chongqing rail transit.  References | Related Articles | Metrics

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Pricing Method of the Urban-rural Public Transportation in Hilly City under Urban-rual Integration WU Lingling，XIAO Liaomei，YIN Huasheng 2016, 35(2): 137-140.  DOI: 10.3969/j.issn.1674-0696.2016.02.28 Abstract ( )   PDF (989KB) ( )   Based on the precondition of urban-rural integration,the certain relation existing between the public passenger bus ticket and the riding comfort level were elaborated by introducing comfort factor and by emphasizing the difference of bus route between hilly city and plain city. Considering that the urban residents’ travel means were limited in hilly city and through questionnaire inquiry, the functional relationship between passenger’s acceptable ticket price and its actual acceptance rate was obtained thus determining the bus price elasticity of demand of urban public transport in hilly city. A pricing model suitable for hilly urban public transport was further determined by considering the influence of governmental financial subsidy on bus ticket pricing, setting up financial subsidy mechanism and in combination with Ramsay pricing model. The feasibility of this given pricing model is verified by a practical case study. References | Related Articles | Metrics

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Research on Highway Engineering Cost Estimation Based on the GA-BP Algorithm PAN Yuhong，ZHANG Yilong，CAI Yajun，WU Huanhuan，SUI Hongyan 2016, 35(2): 141-145.  DOI: 10.3969/j.issn.1674-0696.2016.02.29 Abstract ( )   PDF (1053KB) ( )   Aiming at the problems existing in current highway engineering cost estimation, in combination with respective features of artificial neural network model and genetic algorithm to achieve mutual complement of respective advantages, the artificial intelligence algorithm —GA-BP algorithm model is introduced into the highway engineering cost estimation. The engineering cost data of some completed highways was used in an attempt to find the characteristic values impacting cost and their respective membership degrees. Based on the MATLAB platform, the results of GA-BP algorithm was compared with that of BP algorithm by the simulating experiment. The findings show that the results of sample tests by the two methods all meet expected accuracy and the GA-BP is of higher accuracy meanwhile the results also prove that the optimized GA-BP algorithm is not only simpler and faster but also of high calculation accuracy thus being feasible and effective.  References | Related Articles | Metrics

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Variable Weight Evaluation for Public Transportation Security Capacity of Railway Passenger Terminals GUO Hongyang, LI Hui, LIU Fuhua, LIU Lan 2016, 35(2): 146-150.  DOI: 10.3969/j.issn.1674-0696.2016.02.30 Abstract ( )   PDF (1049KB) ( )   The existing safety assurance evaluation system for hub public passenger transport normally addresses single type of hazard and always uses invariable weighting evaluation method. Where in passenger transportation hub some safety parameters contain defects which cause the inconstance between the evaluation results and reality. A variable weight evaluation method is thus used in the safety assurance system evaluation with consideration of multiple hazard types. On basis of overall consideration of the elements impacting public transport safety, the expert precedence was firstly determined by consistent fusion algorithm; then the variable weight evaluation method was used to evaluate the completeness of the safety assurance system of hub public transport and finally the effectiveness and reasonableness of this method was proved by a practical case. Compared with invariable weight evaluation method with existing problems, variable weight evaluation method can solve those problems existing in safety assurance of public transport meanwhile the calculation results also show that results of evaluation by variable weight method are more close to reality. References | Related Articles | Metrics

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Proactive Evaluation on Sailing Risk of Real-time Ship Traffic in Waterway ZHANG Shukui, ,XIAO Yingjie , SU Wenming 2016, 35(2): 151-155.  DOI: 10.3969/j.issn.1674-0696.2016.02.31 Abstract ( )   PDF (1022KB) ( )   In order to assess sailing risk of real-time ship traffic in waterway and give early warning of accident, the Bayesian network was built by using Gaussian mixture model and maximum expectation algorithm. Through our study and training about Bayesian network structure and parameters and based on the data from ship detectors and the record of traffic accident occurred in Caoxiexia waterway of Yangtze River, BN distributor was established. BN classification models in relation to 8 group data of ship traffic flow were set up respectively. Results show that the model using data taken from the two ship detectors closest to traffic scene within 20 to 40 minutes just before occurrence of accident generates optimum prediction results with accuracy up to 78.13%.The result of comparison among BN, BP neural network and K close neighbor proves that BN prediction model generates a more accurate prediction result and is thus a good method of risk evaluation of sailing ships in real-time.  References | Related Articles | Metrics

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Multi-Unloading Packing Problem Model Research Based on MMAS TIAN Ran, SUN Linfu, TANG Huijia, LI Binyong 2016, 35(2): 156-162.  DOI: 10.3969/j.issn.1674-0696.2016.02.32 Abstract ( )   PDF (1055KB) ( )   Aiming at the packing problems of container truck with multiple loading points, goods variety and multi-truck carriers, cargo loading and unloading sequence for different unloading locations was generated. Mathematical model was set up based on volume, weight and loading-unloading distance and the constraints to various packing types were defined. Firstly, a feasible solution generated as per packing rule and packing constraint served as initial solution by ant colony algorithm. Then, pheromone and selection probability formula was defined in accordance with characteristics of ants route seeking on goods to calculate the optimum solution within certain cycle numbers by max-min ant colony algorithm so as to achieve the goal of maximum loading utilization and maximum volume utilization of goods truck. Finally, the rationality and effectiveness of this method is justified by a practical case. References | Related Articles | Metrics

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Dynamic Model of Block Space Allocation on Container Terminal Yard YAN Nannan, CUI Jingyun 2016, 35(2): 163-168.  DOI: 10.3969/j.issn.1674-0696.2016.02.33 Abstract ( )   PDF (1049KB) ( )   Aiming at the problem of low utilization of container area of storage yard on container terminal, the dynamic space deployment model was set up for solution by using the mathematics planning method, considering the balanced workload between adjacent bays and the number of gantry carne involved and adoption of storage strategy for workload balance. The running results demonstrate that this model can not only determine the actual numbers of the different-sized containers assigned to each bay but also achieve the staggered stacking of containers on different loading and unloading lines thus effectively improving space utilization of storage yard meanwhile improving the loading and unloading efficiency. References | Related Articles | Metrics

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Quay Crane Dynamic Allocation and Scheduling with Bay Research at Container Terminal LIANG Chengji，WANG Dandan 2016, 35(2): 169-183.  DOI: 10.3969/j.issn.1674-0696.2016.02.34 Abstract ( )   PDF (1187KB) ( )   In order to improve the quay crane’s efficiency and service level for vessels at container terminal, aiming at the heavy workload in every bay of multi-vessels, by considering such factors as ship priority, quantity of available quay crane, quay crane collision and safe distance, a mixed integer programming model on dynamic allocation of quay crane for vessels and scheduling and deployment of bay was establizhed in an attempt to minimize vessels’ staying time at container terminal. Through different scales of examples, the results obtained from Cplex and genetic algorithm programmed by C# respectively showed that the proposed model can effectively solve the problems of quay crane allocation and scheduling of multi-vessels and genetic algorithm has shorter computing time and higher quality solution thus verifying the effectiveness of this model and algorithm. References | Related Articles | Metrics

Vehicle & Electromechanical Engineering

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Propeller Shaft and Rear Axle Housing System Vibration Analysis Based on ADAMS ZHOU Haichao，ZHAI Huihui，YANG Jian 2016, 35(2): 174-178.  DOI: 10.3969/j.issn.1674-0696.2016.02.35 Abstract ( )   PDF (1593KB) ( )   According to the powertrain parameter and numerical model simulating axle housing of some motorcar type , a dynamic model simulating propeller shaft-Rear Axle Housing system was established by ADAMS and an analysis was made on the impact of variations of equivalent angle and rotational speed of propeller shaft on vibration response of driving shaft and rear axle housing. The results show that increasing of propeller shaft angle and rotational speed may not only intensify the vibration response of the half axles left and right but also may affect the vibraton response of surface of driving axle housing. The study result lays a foundation for further optimization of powertrain parameters matching. References | Related Articles | Metrics