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Seismic Response of the Large Span Prestressed Concrete Continuous Girder Bridge YU Qian-hua,XIA Pei-hua,SONG Ze-gang,ZHANG Kai 2009, 28(1): 1-4.  DOI: 10.3969/j.issn.1674-0696.2009.01.01 Abstract ( )   PDF (334KB) ( )   In general, large span of continuous prestressed concrete girder bridges only place one fixed buttress. For the bridge span is longer, the vertical seismic response of a fixed pier is also correspondingly larger. Using response spectrum, the impact of the seismic response of different types of bearings bound for a fixed bridge pier and fixed bearing is discussed. The results show that different types of restraint bearing have a greater impact on the seismic response of continuous bridge. At the same time, the impact of pile-soil interaction on continuous bridge dynamic characteristics and the seismic response is also analyzed. The results of this research can provide references for the anti-seismic design of similar bridges. References | Related Articles | Metrics

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Variat ional Solution of Shear Lag E ffect of Box G irder in H igh Order D isplacement Function CHEN Chang-song,DENG An 2009, 28(1): 5-7.  DOI: 10.3969/j.issn.1674-0696.2009.01.02 Abstract ( )   PDF (212KB) ( )   Considering the shear lag longitudinal displacement, five times and six times parabola are adopted respectively to reflect the changing range of shear lag effect of thin wall box girders. And the calculation formula and boundary conditions of corresponding differential functions of shear lag effect are obtained by the adoption of energy variation method. According to the changing rules of different parabolic function of the displacement of shear lag effect in several common loading and bearing forms, a comparison between them are carried out. The results show that the vertical displacement box function is more precise when times get higher than three times parabola adopted in usual shear lag effect, which offers references and guides to the further study of shear lag effect. References | Related Articles | Metrics

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Calculation of B earing Capacity of AxialCompression Short Column w ith Round Cross??Section Reinforced by Enlarging Cross??SectionM ethod XIE Li-dong,LIU Han-bing 2009, 28(1): 8-10.  DOI: 10.3969/j.issn.1674-0696.2009.01.03 Abstract ( )   PDF (254KB) ( )   Axial compression short colunm with round cross-section is reinforced by enlarging cross-section method, for it is short of bearing capacity. In order to study the destruction limits and the bearing capability of normal cross-section of rein- forced column, the radical stress of the reinforeed column is obtained through the iterative numerical solution, according to the force balance of concrete at the junction of old concrete and new concrete. The vertical compressive strength of old concrete is calculated by tri-axial stress ; the compressive strength of new concrete is calculated by pulling in ring and pressing in longitude. When pulling-strain of the new enclosed concrete reaches the strain limits, the new concrete rips; meanwhile, the strengthened column reaches the destruction limits. References | Related Articles | Metrics

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Study on Spatial Stability ofMobile Bailey Truss Structure LI Wen-bin,LEI Jian-qiang,ZENG De-rong 2009, 28(1): 11-15.  DOI: 10.3969/j.issn.1674-0696.2009.01.04 Abstract ( )   PDF (587KB) ( )   Taking the southern approach bridge of Yudong Yangtze River Bridge as the research object, which applies the cast-in-place construction technology to continuous box girder on Bailey beams stent, the stent-reaction forces under different conditions of cast-in-place box girder are obtained through Dr 3.0 bridge finite element analysis software. Then Bailey truss structure model established by ANSYS 9.0 finite element analysis software is applied to check the spatial stability in the construction of Bailey truss structure. The relevant stability coefficients and the corresponding instability modes are obtained. Eventually, relevant recommendations to prevent such instability of Bailey stent are given. References | Related Articles | Metrics

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Test Study on theN ew Method of Bearing Replacement of Simple Support??Continuous G irder Bridge GUO Yan-fen,ZHANG Yong-shu,WAN Fei,HU An-lin 2009, 28(1): 16-19.  DOI: 10.3969/j.issn.1674-0696.2009.01.05 Abstract ( )   PDF (522KB) ( )   The simple support-continuous girder bridge is widely used in the highway construction. With the increase of operation period of bridge, the issues of bearing replacement must be faced. Aiming at the case of transforming the high piers bridge with simple support to T continuous girder bridge on the Shuima Highway in the mountainous area, and the new method of bearings replacement is put forward by model test. This method is called longitudinal single-point（ followed by pier）, lateral synchronous jacking-up. Taking the safety of girder body in the lifting process as the goal, the limits of lifting bearings for T girder bridge of 20, 30 and 40 meter span are obtained respectively. The results show that the new method ＂longitudinal single-point（ followed by pier）, lateral synchronous jacking-up＂ is reasonable and feasible, and the structural safety is assured. It has provided a new method and a new way for bearing replacement of similar bridges. References | Related Articles | Metrics

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Influence Analysis on Catwalk Load in the Construction Control of Suspension Bridge LU Yi,YAN Dong-huang,CHEN Chang-song,LIU Wen-Deng 2009, 28(1): 20-22.  DOI: 10.3969/j.issn.1674-0696.2009.01.06 Abstract ( )   PDF (354KB) ( )   Taking Beipanjiang Bridge in Guizhou Province as an example, the catenary element calculation method is adopted to calculate the erecting parameters of catwalk construction, with the consideration of unbalanced horizontal force produced by the catwalk side mid-span separation and the influences the catwalk load has on the parameters of construction control of suspension bridge. The engineering practice indicates that this method is accurate and can provide the references for the calculation of catwalk construction and the construction control of suspension bridge. References | Related Articles | Metrics

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Optimization Design of Loading Procedure of Trestle Construction of Arch Bridge HUANG Ze-quan,MEI Gai-wei,YANG Xing 2009, 28(1): 23-25.  DOI: 10.3969/j.issn.1674-0696.2009.01.07 Abstract ( )   PDF (268KB) ( )   Taking Heping Bridge engineering as an example, the deformation of arch scaffolding loading procedure and stress calculation of drafted by construction units are carried out. Aiming at the problem of ＂W＂ deformation and inhomogeneous stress of the arch scaffolding, some general principles of optimizing trestle construction loading procedure are put forward and the method of temporary pre-loading near arch crown in the process of loading has been carried out. Then, the crude loading procedure is optimized by finite element program. The result indicates that the optimized procedure of construction loading makes the arch scaffolding deformation and stress become reasonable. Therefore, the goal of optimizing the loading procedure is realized References | Related Articles | Metrics

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On Digital Presentation of the Construction Process of B ridges via V irtualReality Technology CHEN Zheng-bin,YIN Xiang-lin 2009, 28(1): 26-28.  DOI: 10.3969/j.issn.1674-0696.2009.01.08 Abstract ( )   PDF (259KB) ( )   The concept of virtual reality technology and its application in bridge construction are introduced. The basic methods of the application of virtual reality technology in bridge construction and the prospect of the application are also explored, which will be significant to the design of bridge construction plan and the control of construction. References | Related Articles | Metrics

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Study on Mechanical Behavior of Tunnel Construction at Fault Zone with High Ground Stress LI Peng,LIN Zhi,ZHANG Ya-xing 2009, 28(1): 29-32.  DOI: 10.3969/j.issn.1674-0696.2009.01.09 Abstract ( )   PDF (709KB) ( )   Using the finite-difference software FLAC^3D, numerical simulation of the mechanical properties of construction and the effects of deformation space in the project with the tunnel at the fault zone with high ground stress is carried out. The space effect of excavation face is analyzed. The displacement which occurs at arch top, the skewback, surrounding rocks and boundary wall and the rule of rock＇s stress changing with the procedure of construction are focused, which offers referential basis to the optimum design and construction. References | Related Articles | Metrics

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Simulation of Supporting Effect of Tunnel Excavation in Fragment Strip DU Yong-bin 2009, 28(1): 33-35.  DOI: 10.3969/j.issn.1674-0696.2009.01.10 Abstract ( )   PDF (792KB) ( )   Excavating the tunnel under the complex geologic condition like fragment strip involves factors from various aspects. Sufficient geologic information is used to describe a certain tunnel in detail, including lithology, occurrence and other parameters which can be gained in practice work. Then the stability of wall rock resulting from excavation in fragment strip is simulated by particle flow code. The corresponding relations between laboratory parameters and ones used in PFC are finally found out through a large number of calibration tests. So the supporting model with liner and the one without liner are established. The displacement of wall rock and the change of tension stress near the section of the tunnel are compared on the base of 2 models mentioned above. The supporting effect of liner structure is evaluated. It can provide referential value for underground projects under similar geologic conditions. References | Related Articles | Metrics

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Study on Numerical Simulation of Crack Growth ofConcrete Based on XFEM DONG Yu-wen,REN Qing-wen 2009, 28(1): 36-40.  DOI: 10.3969/j.issn.1674-0696.2009.01.11 Abstract ( )   PDF (771KB) ( )   Extended finite element method（XFEM） is a new and effective method for analyzing discontinuity problem arisen in recent few years, specially the problem of fracture. The basic theory of XFEM is introduced and the method of analyzing concrete fracture and crack growth is presented. Finally, the fracturing process of two samples including initial cracks and the crack growth process of the concrete gravity dam are simulated by XFEM. The discipline of displacement and stress field distribution of the samples are analyzed. Comparing with classical finite element method, the crack growth of concrete can be simulated by XFEM without making the crack surface associated to the mesh, without setting dense mesh near the crack tip and without re-meshing after crack growth. Thus the cumbersome works and disadvantages in fracturing analysis are avoided by the application of XFEM. The unique advantage of XFEM in concrete fracturing analysis is displayed. References | Related Articles | Metrics

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Experimental Study on the Durability and Impact Resistance of Fiber Reinforced Concrete Structure GONG Bin,WANG Fu-min,WU Chang-hong,LI Ying 2009, 28(1): 41-44.  DOI: 10.3969/j.issn.1674-0696.2009.01.12 Abstract ( )   PDF (479KB) ( )   Impact resistance performance of the fiber reinforced concrete means the capacity of composite materials absorbing the kinetic energy under repeated impact load. Contrastive experiments of the impact resistance performance are carried out between alkali-resistant glass fiber reinforced concrete, polypropylene fiber reinforced concrete, reinforced concrete and ordinary concrete. The results of the experiment draw the conclusion that adding flexible fiber into the concrete can obviously improve the impact resistance of concrete and it is also advantageous to enhance the durability of the concrete structure. References | Related Articles | Metrics

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Performance Comparison of Unfold Capability of Crack in the Course of Concreting between Different Flexible FiberDust Plasma YANG Shi-cong,WANG Fu-min 2009, 28(1): 45-48.  DOI: 10.3969/j.issn.1674-0696.2009.01.13 Abstract ( )   PDF (377KB) ( )   The early crack of concrete is ubiquitous phenomenon in the engineering. Cracks seriously affect the durability of concrete, which is a hot research topic. The performance comparison tests of unfold capability of crack in the course of concreting are carried out between several flexible fiber dust plasma samples, in order to study the crack-resistance effect of different flexible fibers have on dust plasma samples at the same condition, which offers certain references to the design, construction and reinforcement of the bridge. References | Related Articles | Metrics

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Analysis on Crack Causes of Semi??Rigid Base of Asphalt Pavement under Load ZHAO Lei,FAN Tong-jiang,HE Zhao-yi,LI Chao 2009, 28(1): 49-53.  DOI: 10.3969/j.issn.1674-0696.2009.01.14 Abstract ( )   PDF (1032KB) ( )   Elastic fracture mechanics theory and finite element method are used to calculate the stress intensity factors of crack, and Paris formula is used to calculate the fatigue life of asphalt pavement. It is proposed that the semi-rigid base of asphalt pavement easily resulting in reflective cracking may be due to the thin layer of asphalt, the low stiffness of asphalt surface and the high siffness of base. The influence of the change of base＇s compressive modulus on the fatigue life of asphalt pavement is more significant than that of the change of surface＇s compressive modulus on. The asphah pavement fatigue life has enhanced greatly with the increase of surface＇s thickness. References | Related Articles | Metrics

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Application of Inclined Plane Shear Test to Asphalt Mixture WANG Rui-lin,YU Miao 2009, 28(1): 54-55.  DOI: 10.3969/j.issn.1674-0696.2009.01.15 Abstract ( )   PDF (159KB) ( )   Using inclined plane shear instrument to carry out the shear test of asphalt mixture, the best shear blade pitch in minimum of the standard deviation and coefficient of＂ variation can be got by adjusting the edge pitch of blades. And then the biggest shear strength of asphalt mixture is obtained, furthermore, the accuracy of the results is verified by uni-axial penetration test. The results show that the inclined plane shear test can accurately determine the largest shear strength of asphalt mixture. Its testing method is simple and feasible, and it can be applied and promoted in the shear test of asphalt mixture. References | Related Articles | Metrics

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Study on Pavement Performance of Nanometer Layered SilicateModified AsphaltM ixture HUANG Wei-rong 2009, 28(1): 56-59.  DOI: 10.3969/j.issn.1674-0696.2009.01.16 Abstract ( )   PDF (462KB) ( )   Marshall Test is adopted to determine the optimal asphalt-aggregate ratio of base asphalt, rosin-based nanometer layered silicate and SBS asphalt mixture. And contrastive tests between these three kinds of asphalt mixtures are carried out to test the pavement performances, such as high temperature stability, low temperature stability and water stability. The results show that compared with base asphalt, the high temperature stability and water stability of nanometer layered silicate modified asphalt are improved significantly; and the modified effect of nanometer layered silicate modified asphalt is equivalent to that of SBS asphalt mixture. So it has high application value in the actual project. References | Related Articles | Metrics

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Research on High Temperature Creep Test of Asphalt Mixture WANG Jin-he 2009, 28(1): 60-62.  DOI: 10.3969/j.issn.1674-0696.2009.01.17 Abstract ( )   PDF (119KB) ( )   Asphalt mixture is a viscoelastic material with grain composition. Grain composition of asphalt mixture determines the higher stress level is adopted in uni-axial creep test at normal temperature. Only lower stress level can be adopted at high temperature, or the sample will be undermined in advance. However, the load is always heavier than 0.8 MPa and the pavement temperature is over 60℃ in the service period. Therefore, the thick rutting plats（30cm × 30cm × 10cm）are used in uni-axial penetration creep test（ that is, single axis penetration creep test）. Making use of the lateral restraint thick rutting plats provide for the asphalt mixture under load, a reasonable test method for the investigation of viscoelastic proper- ties of asphalt mixture under heavy load and at high temperature is obtained. References | Related Articles | Metrics

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Study on Moving Feature of Bituminous Mixture Flow in Distributing Room LU Zhao-feng,QIN Min,GUO Xiao-hong 2009, 28(1): 63-66.  DOI: 10.3969/j.issn.1674-0696.2009.01.18 Abstract ( )   PDF (418KB) ( )   Based on the physical characteristics of bituminous mixture in the process of paving, hydromechanics is put forward to study the bituminous mixture flow＇s movement feature in the spiral-feeder. The flow patterns and corresponding flow characteristics of laminar flow and turbulent flow are explored and the transmission mechanism of spiral-feeder of asphalt paver and the moving law of asphalt mixture aggregates are analyzed. Through the theoretical mechanics and hydromechanics analysis, the movement mechanism of mixture aggregates is revealed, which can provide the reliable basis for improving the design of screw-feeder and paver construction technology. References | Related Articles | Metrics

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Investigation and Analysis on the Interior and Exterior Noises byM icro-SurfacingMaintenance T echnology DUAN Xu-bin,LIU Yu-heng,LI Zhi-dong,HUANG Xiao-ming 2009, 28(1): 67-73.  DOI: 10.3969/j.issn.1674-0696.2009.01.19 Abstract ( )   PDF (858KB) ( )   Micro-surfacing is a preventive maintenance technology, which is economic, convenient and effective. It plays a key role nowadays in China, where the highway is developed rapidly. However, interior noise of micro-surfacing is higher than that of HMA. In order to guide the indoor tests and construction practices, the interior and exterior noises of typical section are investigated by micro-surfacing maintenance technology, and the variation characteristics and their relevant influence factors are analyzed. References | Related Articles | Metrics

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Discussion on Pre-Cracking Spacing of Cement Stabilized Crushed Stone Base HU Xue-liang,YANG Wen-jun,ZHU Hong-zhou,WEI Gang 2009, 28(1): 74-76.  DOI: 10.3969/j.issn.1674-0696.2009.01.20 Abstract ( )   PDF (190KB) ( )   Basing on the basic theory of elasticity, the computation formula of the pre-cracking spacing of cement-stabilized crushed-stone base is proposed, with the consideration of stress-reduction and shrinkage stress on the impact of cracks. And then the relationship among basic thickness, temperature difference and the spacing of pre-cracking is analyzed. Taking Chongqing region as an example, the recommendation values of the spacing of pre-craeking at different basic thickness are given. References | Related Articles | Metrics

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Research on Thickness of Particle Improved Roadbed Based on IntervalAnalys is HUANG Ming-kui, 2009, 28(1): 77-79.  DOI: 10.3969/j.issn.1674-0696.2009.01.21 Abstract ( )   PDF (162KB) ( )   In mechanical analysis and design of roadbed engineering in permafrost, it is difficult to get a large amount of data samples. However, the numerical range of basic parameters which affect the design and application of the roadbed can be determined, because of the complexity of the environment and correlative parameters as well as the limitation of information. Therefore, the basic parameters which influence the thickness of particle improved roadbed are taken as the interval variables. The interval analysis method is adopted to study the thickness, which can overcome problems mentioned above. It is showed that the interval approach has good adaptability in engineering practice. References | Related Articles | Metrics

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Correlation Study on Strength Parameters of Slide Surface Silty Clay of Landslide in Chongqing Reservoir Area LUO Hong,TANG Hong-mei 2009, 28(1): 80-83.  DOI: 10.3969/j.issn.1674-0696.2009.01.22 Abstract ( )   PDF (418KB) ( )   Landslide is a kind of main geological disasters in Three Gorges Reservoir area. To landslide, the slide surface soil is an important component which relates closely to the deformation development and stability evaluation, so it is a key problem to study the shear strength parameters of these soils in stability evaluating and slide resistant designing. Most of the slide surface soil of the landslides along Three Gorges Reservoir in Chongqing is silty clay. The geological survey reports of representative landslides in Chongqing are collected. Taking strength parameters the slide soil as the research object, studies are mainly concentrated on the samples got from the site of the landslide and survey reports. The correlation among the natural peak strength, residual strength, saturated peak strength, residual strength by the conventional direct shear test in laboratory, and the correlation between the strength parameters from conventional direct shear test in laboratory and in situ are deduced. Then the regression equations among these strength parameters are established, and the characteristics of strength parameters under different test conditions are revealed finally. References | Related Articles | Metrics

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SOM Neural Network Judgment and Validation on Swelling and Shrinking Grade of Expansive Soil BAO Ling-gao,LIANG Xiang 2009, 28(1): 84-89.  DOI: 10.3969/j.issn.1674-0696.2009.01.23 Abstract ( )   PDF (515KB) ( )   The existing approaches to identify and classify expansive soil have been evaluated. The indices that can reflect and characterize the swell-shrink mechanism and properties are analyzed. Making use of six indices such as liquid limit, plasticity index, less than two microns glutinous granule percent, CBR, free expansion ratio and CBR expansion ratio, the swelling and shrinking grade model on the theoretic base of SOM neural network model is established through determining the limit value of every, index. And the judgment software is also progrannned. Furtbermore, the judgment model is applied to judge and classify the swelling and shrinking grade of expansive soil samples. The model is tested by other two indices besides the six indices of expansive soil mentioned above, that is, swelling and shrinking performance and strength performance. The classification is proved correct and credible. References | Related Articles | Metrics

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Optimization of Support ing Parameters for Treating H igh L iquid L imit Soil Slope by SoilNails WU Guo-xiong,GUO Guo-he,XIN Shu-jie 2009, 28(1): 90-94.  DOI: 10.3969/j.issn.1674-0696.2009.01.24 Abstract ( )   PDF (546KB) ( )   Soil nailing has been widely used in slope engineering, but so far there are no norms that the soil nailing parameter selection carl conform to. Based on the finite difference method FLAC software, orthogonal design for numerical simulation is used to get a reasonable range of soil nailing parameters under a certain slope height, and the example of typical soil nailing is selected to evaluate the supporting effect, and then the slope safety coefficient and the largest horizontal displacement before and after＇ treatment are compared. The test results show that slope stability has been greatly increased by selecting the reasonable supporting parameters of soil nailing based on the orthogonal test. The results of soil nailing can be used as references for quantitative design of soil nailing. References | Related Articles | Metrics

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Research and Practice on Earth Fill Reclamation of the Reservoir Bank Protection Technology CUI Zhi-bo,CHEN Hong-kai,CHEN Tao 2009, 28(1): 95-99.  DOI: 10.3969/j.issn.1674-0696.2009.01.25 Abstract ( )   PDF (993KB) ( )   Following the principle of organically combining earth-fill reclamation with bank protection, the protective technology of the reservoir bank is explored, which is of important practical significance to beautify and improve the urban function as well as increase the urban land. Taking the Ningjiangdao general harness project of Wushan in Three Gorges Reservoir area as an example, the bank protective technology with the consideration of reclamation is proposed and applied to earth-fill reclamation about 100 Mu. This technology consists of several elements, such as the reservoir bank foundation treatment, riprap protection, rockfill dam, rolled backfill soil, slope surface protection and gravity retaining wall. The stability under different conditions is analyzed, and the conclusion that taking dead weight and water level fall from 175m to 145m as the control condition is reasonable is drawn. The subentry design of design approach is explicated in detail. The quality control of earth-fill compaction problem is also explored. Research results show that the area of 3m on the surface of slope is usually the un-compacted area. Partial collapses always occur in the period of water level falling and the potential danger of crack exists. Thus the structure of protective slope and the grouting treatment method arc proposed. References | Related Articles | Metrics

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Analysis on Macro Geography Background of Landslide Development at ThreeGorges Reservoir Area and Nearby LIANG Xue-zhan,TANG Hong-mei 2009, 28(1): 100-104.  DOI: 10.3969/j.issn.1674-0696.2009.01.26 Abstract ( )   PDF (489KB) ( )   Landslide disasters at Three Gorges Reservoir area and nearby are constrained by the geological structure, geomorphologie units, lithology, precipitation and other factors. The eonstruetion-lithology-geomorphologie combination of conditions is in control of the formation and distribution of landslide geological disasters. Strong new teetonie movement controls the convergence of landslide distribution. The large-landslides mainly distribute near the geomorphologie ladder; tectonic stress field is closely related to the direction of landslides. Landscape of deep valleys and abundant rainfall is helpful to the landslide development; the development of landslide is essentially a kind of geomorphologie development, formation and change in the process. On this basis, taking Yangjiawuchang landslide as an example, the macro background of landslide development of Three Gorges Reservoir area and nearby is analyzed in order to have a new understanding and further research on the landslide development in this area. References | Related Articles | Metrics

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Design of Road Traffic Safety Color System Based on Color Perception XU Hong-liang,ZHANG Tai-xiong,TANG Bo-ming,LIU Tang-zhi 2009, 28(1): 105-107.  DOI: 10.3969/j.issn.1674-0696.2009.01.27 Abstract ( )   PDF (309KB) ( )   Combining with the traffic psychology, the theoretic basis of color perception is introduced. Then its practical application in the road traffic safety field is discussed. At last, the design framework and attentive factors of the road traffic safety color system are proposed on the basis of the psychological effects the color perception has on the human and the identification resulting from different environment under different weather condition, which provides reference for improving the safety level of driver＇s driving behavior and road. References | Related Articles | Metrics

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Mechanism Analysis on Conflicts and Collisions Caused by Aggressive Pedestrian Crossing Single Lane LU Si-wen,FANG Shou-en,WANG Jun-hua 2009, 28(1): 108-110.  DOI: 10.3969/j.issn.1674-0696.2009.01.28 Abstract ( )   PDF (159KB) ( )   According to traffic conflict technique, the mechanism of pedestrian-vehicle conflict and collision is studied when aggressive pedestrians cross the single lane, and the probability models of single-lane pedestrian-vehicle conflict and collision are established. Then the specific probability values are calculated by the Bayesian statistics. The calculation out- comes show that the aggressive crossing pattern is one of the primary reasons for the pedestrian-vehicle conflict and colli- sion; the vehicle volume, instant velocity, reflection time are also the ingredients for crash. The research results will provide not only the references for the reasonable implement of traffic regulations measures on pedestrians＇ safety at the intersection and segment, but also the thought to develop the in-vehicle ITS against the pedestrian-vehicle crash and to simulate the safety of pedestrians crossing street. References | Related Articles | Metrics

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Discussion on Quantitative Evaluation Method of Urban Traffic Satisfaction XIAO Yu-min 2009, 28(1): 111-115.  DOI: 10.3969/j.issn.1674-0696.2009.01.29 Abstract ( )   PDF (270KB) ( )   Through the investigation and analysis of a variety of statistical data of several cities＇ traffic satisfaction, three main factors influcncing the traffic satisfaction are analyzed, such as air and noise pollution, energy useless depletion and traffic situation. Mathematical model is established to test the residents＇ traffic satisfaction. Through the quantitative description of urban road density, the number of motor vehicles and the influencing factors on environment, the weight of various factors in the model is obtained. To test whether the ultimate quantitative data of this model can represent the satisfaction of residents on local traffic situation actually and effectively, the calculation＂ results of traffic satisfaction of various places and their possibilities of actual causes are given, thus the correctness of this model is verified. References | Related Articles | Metrics

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Application of Key Factor Analysis Method to the Calculation of Elastic Coefficients ofH ighway Passenger Transportation REN Qi-liang 2009, 28(1): 116-120.  DOI: 10.3969/j.issn.1674-0696.2009.01.30 Abstract ( )   PDF (244KB) ( )   In order to analyze the effect so many factors have on highway passenger demand and reveal the relationships between them roundly and effectively, the proposal that highway passenger factors are divided into economy factors and elastic factors and the key factor analysis method about elastic coefficients of highway passenger transportation is given. Using key factor analysis method, the highway passenger indexes from 1980 to 2005 of Jiangxi province are computed and the elastic coefficients of highway passenger transportation are got by analyzing the relationship between economy factors and elastic factors. The result shows that key factor analysis method is useful to analyze the highway passenger demand because it can reduce the amount of variables for models and cannot result in the loss of much information, and then it shows that all ＋the elastic coefficients change a little, which can reflect the relationship between highway passenger transportation and social economy. And the development trend of elastic coefficients got from geometric average method changes more gently and the fluctuation range is smaller than that got from arithmetical average method. References | Related Articles | Metrics

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A Novel Method of Confirming the Boarding Station of Bus Holders YU Yong,DENG Tian-min,,XIAO Yu-min 2009, 28(1): 121-125.  DOI: 10.3969/j.issn.1674-0696.2009.01.31 Abstract ( )   PDF (600KB) ( )   A new way of collecting passenger flow information comes into being since the intelligent cards are used in public transport charge systems. The data recorded by these intelligent cards can help transport service providers obtain a large amount of statistic data they need. Confirming the boarding station of bus IC card holders is studied through the existing IC card data. At first, the hierarchical clustering method is adopted to classify the source data according to the minimum time interval between two passengers using IC card to get on the bus in adjacent stations. Then, the prediction value of the bus arrival time at each stop can be obtained from the bus schedule information. On the basis, the boarding station of bus IC card holders can be confirmed by the time matching between the results from IC card data and the bus arrival time at each stop. Finally, the feasibility and practicality of the method is proved by actual examples. References | Related Articles | Metrics

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Calculation of the Longitudinal Depth Averaged Velocity D istribution of Curved Conduit Flow TONG Si-chen,GAO Jian,XU Guang-xiang,ZHONG Liang 2009, 28(1): 126-129.  DOI: 10.3969/j.issn.1674-0696.2009.01.32 Abstract ( )   PDF (393KB) ( )   The hydraulic characteristics of curved conduit flow arc one of the most interesting subjects to hydraulic researchers. Among them the longitudinal depth averaged velocity distribution is an important topic. A generalized curved conduit flow experiment was employed to obtain the longitudinal velocity parameters by adopting the ADV to measure the 3D flow velocity data. Based on the calculation methods of water surface transverse gradient and longitudinal gradient in curved flow, a longitudinal depth averaged veloeity distribution formula was theoretically established to explore the bend flow charaeteristics. Results show that the calculated data agree well with the measured ones, which provides a theoretic basis to explore the hydraulie characteristics profoundly References | Related Articles | Metrics

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Application of Hinge Concrete Sinking Platoon to Waterway Regulation Engineering from Huaibin to Sanhejian in Huaihe River ZENG Ya-dong,ZHANG Xu-jin 2009, 28(1): 130-133.  DOI: 10.3969/j.issn.1674-0696.2009.01.33 Abstract ( )   PDF (250KB) ( )   The segment of waterway from Huaibin to Sanhejian in Huaihe River with many long shoals has seriously hampered the development of shipping and needs the rectification. However, the situation of the Huaihe River flood control is grim, so the traditional dams and other buildings which jam the flow of water can＇t be used in the waterway regulation of this segment. The rectification measures with the combination of dredging and concrete hinge row to protect the beach are proposed and the width, length, spacing and stability of concrete hinge row are studied. References | Related Articles | Metrics

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Application of GIS to Port and Waterway Management of Lancang??Mekong River LIN Xiao-song,XU Xi-bin,ZHOU Fu-chun,YU Qing 2009, 28(1): 134-138.  DOI: 10.3969/j.issn.1674-0696.2009.01.34 Abstract ( )   PDF (665KB) ( )   With the rapid development of the inf~rmational teehnology, tire traditional port and waterway management is increasingly unable to meet tire modern needs of the development of shipping traffic. As a result, the construction of the port and waterway geographic information system and the realization of the modernization of port and waterway management are imperative. Laneang-Mekong River is an important international waterway of strategic： importance. The application of GIS to port and waterway management of Lancang-Mekong River is discussed on the basis of GIS main functions and four aspects are foeused, that is, the data storage and management, information performance and visualization, spatial analysis and simulation as well as information output and sharing References | Related Articles | Metrics

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Study on Locating and Navigating Conditions of Heavy Cargo Wharf at Xiangjiaba Hydropower Station in Jinsha River LIU Ya-hui,CHEN Xue 2009, 28(1): 139-141.  DOI: 10.3969/j.issn.1674-0696.2009.01.35 Abstract ( )   PDF (197KB) ( )   In order to ensure the security and reliability of the transportation, loading and unloading of heavy cargo for Xiangjiaba hydropower station in Jinsha River, it is required to have a contrasting test study on several wharf locations and their corresponding wharf types which are designed in the preliminary process, including the layout of the project, water area conditions, ship entering-departing conditions, wharfing loading-unloading conditions and their influence on waterway of Jinsha River. Meanwhile, the recommendation project and advice are put forward, which will provide a scientific basis for the location and design of heavy cargo wharf. References | Related Articles | Metrics

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Analysis on Spatial??Temporal Evolution of Expansion of Macao Urban Built Up Area MU Feng-yun,,ZHANG Zeng-xiang 2009, 28(1): 142-146.  DOI: 10.3969/j.issn.1674-0696.2009.01.36 Abstract ( )   PDF (247KB) ( )   Making use of two MSS images, four Landsat TM images and one ETM ＋ image, which are well accordant with the location and corrected accurately by geometrics, the dynamic monitoring of expansion of Macao urban built-up area from 1973 to 2004 is carried out. The hierarchical classification method and truman-computer interaction and visual interpretation method are adopted in the monitoring process to obtain the changes of built-up area at different time and the expansion speed at different monitoring periods. The result shows that the urban built-up area in Macao increases by 16.02 km^2 during the past 31 years and increased by 0.52 km^2 per year. The expansion of Macao urban built-up area is influenced by many factors, in which the national（regional） policies and the economic development are the most manifest ones. References | Related Articles | Metrics

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Stochastically Optimal Research on Empty Container Reposition at Sea WANG Bin,TANG Guo-chun 2009, 28(1): 147-150.  DOI: 10.3969/j.issn.1674-0696.2009.01.37 Abstract ( )   PDF (171KB) ( )   The chance-constrained programming is used to do a stochastically optimal research on empty container reposition at sea. The objective function of this model is to minimize the costs of reposition and renting. The restricted conditions should meet the following factors including the requirement of empty containers, the ability of supply and storage of empty containers, time limit and load limit of empty containers. Probability distribution function is adopted to transform chance- constrained condition into contain constraint condition, thus the stochastic programming is transformed into certain programruing model. The computing result shows that the model can reduce the reposition costs effectively. The model gives an effective method about the reposition of empty containers for a shipping company. References | Related Articles | Metrics

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Research on the Management of Supplier Selection and Stock Strategies Based on C lassification of EnterpriseMaterials CHI Jie,WU Peng 2009, 28(1): 151-155.  DOI: 10.3969/j.issn.1674-0696.2009.01.38 Abstract ( )   PDF (457KB) ( )   Aiming at the disadvantages of current evaluation index system of supplier, it is proposed to start from the classification of enterprise materials and then classify suppliers accordingly. Corresponding selection index systems for different kinds of suppliers are established and Analytic Hierarchy Process （AHP） is used to choose the best suppliers. Then the comprehensive value and order for each supplier in terms of the evaluation index are quantificationally acquired. Finally, linear programming is used to establish a model for distributing stock materials between suppliers. References | Related Articles | Metrics

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Optimal Condition for a Kind of Multi??Objective Fractional Programming w ith D ifferentialConvexity Functions PENG Zai-yun,LEI Ming,LIU Ya-wei,TAN Yuan-shun 2009, 28(1): 156-157.  DOI: 10.3969/j.issn.1674-0696.2009.01.39 Abstract ( )   PDF (135KB) ( )   A class of multi-objective vector fractional programming problem （VFP）is studied. Under the condition that fi（x）≤0（i=1,2,…,ρ）,ρ（x）〉0,and f（x）、g（x）、ρ（x） are differential convex functions, the Kuhn-Tucher optimal condition of the muhi-objective vector fractional programming problem is discussed. References | Related Articles | Metrics

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A New Solution of Linear Differential Equations with Constant Coefficient CHEN Chun-bao,SHEN Jia-hua,DING Song-kang 2009, 28(1): 158-160.  DOI: 10.3969/j.issn.1674-0696.2009.01.40 Abstract ( )   PDF (129KB) ( )   Differential equation is of great importance in the advanced Mathematics. The solution method of second-order coefficient of linear differential equation is studied in general literature and textbooks, that is, undetermined coefficient method. The explanation of constant coefficient of linear differential equations to be determined index and non-homogeneous factor to be determined explanation is given, and a new method -- reduced order method is proposed and studied. References | Related Articles | Metrics