交通运输工程学报

Modeling of key components in vehicle dynamics simulation

Shen Gang, Zhou Jing-song, Ren Li-hui

Abstract: In order to improve the modeling precision of nonlinear components' mathematics models in vehicle dynamics simulation, the dynamics properties of one/two dimension columbic friction pairs, the friction wedge of three piece bogies and the damper with series stiffness were analyzed, their unconventional mathematics models were set up without velocity variable, their Simulink programs were designed, and their characters were compared with traditional models. Analysis result shows that the models overcome the numerical computation problems resulted from traditional models, have higher computational precision and efficiency, and their computational velocities increase by 2~10 times according to the scales of the models and the numbers of their nonlinear components. 24 figs, 10 refs.More>

2007, 7(5): 1-5.

FullText HTML (72) PDF (208KB) (277)

Vibrant response characteristic of railway vehicle

CHI Mao-ru, ZHANG Wei-hua, CENG Jing, DAI Huan-yun, WU Ping-bo

Abstract: In order to improve the riding comfort of vehicle, the vibrant response characteristic of vehicle was studied, a dynamics model of vehicle system was set up, frequency-domain mode parameters on the hunting mode of bogie and the natural mode of car body were calculated, and stationarity indices of vehicle at the different speeds were computed in time-domain.Computation result shows that the hunting frequency of bogie and the primary frequency of track irregularities increase with the increase of running velocity, but the natural frequency of car body has no change; they must approach the natural frequency of car body and take place resonance at certain speed, and the resonance will badly worsen the riding comfort of vehicle.So in order to improve the comfort, some proper measures should be taken to keep the resonance speed away from the common running speed of vehicle.More>

2007, 7(5): 6-11.

FullText HTML (123) PDF (292KB) (597)

Dynamics model of secondary lateral stopping block of vehicle

LIU Jian-xin, WANG Kai-yun, FENG Quan-bao

Abstract: In order to discuss the effect of vehicle stopping block on vehicle dynamics, a dynamics model of secondary lateral stopping block was put forward, and its characteristics of dynamic interaction and stopping displacements in time and frequency domains were analyzed.Analysis result shows that the model has strong nonlinearity, stopping block can effectively restrict the lateral displacement of vehicle, and it decreases by 30 mm; the block has great influence on the lateral vibration of vehicle, the lateral force of wheel-rail has fluctuation in curve, the main frequency of the block is not more than 4 Hz, and its range accords with the main frequency range of lateral vibration acceleration of vehicle.More>

2007, 7(5): 12-14.

FullText HTML (86) PDF (146KB) (517)

Influence of air spring on curve negotiating property of vehicle

LUO Ren, CENG Jing, WU Ping-bo

Abstract: The coupled vertical model of left and right air springs was considered, a mathematical model of vehicle system was set up, the dynamic equations of air spring were derived from the state equations of ideal gas, and the dynamic performances of vehicle and air spring were simulated when vehicle passed through curve.Simulation result shows that because of the action of leveling valves, the pressures of air springs are different, so that the displacement of car body does not tend to zero after curve negotiation; when vehicle runs along curve at normal speed, its dynamic curving performance varies little; when vehicle passes through the same curve time after time, the pressure's mutative range of air spring is certain; the increase of anti-roll stiffness reduces the roll angle of car body and the pressure change of air spring; the lateral distance increase between air springs and choosing appropriate stiffness and damping of air spring may keep the pressure of air spring tending to its static equilibrium value after vehicle passes through the curve.More>

2007, 7(5): 15-18.

FullText HTML (80) PDF (192KB) (279)

Analysis method of dynamic responses on slab track

ZHAO Huai-yun, LIU Jian-xin, ZHAI Wan-ming

Abstract: In order to calculate the dynamic responses of slab track subjected to moving vehicular loads, slab was treated as linear viscoelastic continuously supported beam, rail was modeled as linear viscoelastic discretely supported beam, track and slab were regarded as a whole and represented by using finite elements, vehicle-track coupling dynamics theory and total potential energy principle with stationary value in elastic system dynamics were applied, a vertical dynamic coupling model of high-speed train and slab track was established, its dynamics equations were set up, and wheel and rail dynamic responses at the weld joint of slab track were calculated.Simulation result shows that comparing with existing methods, the variational trends and ranges of their computation results are basically consistent, so the model is feasible.More>

2007, 7(5): 19-23.

FullText HTML (97) PDF (216KB) (175)

Frequency variety analysis and equivalent algorithm of metal spring stiffness

LIU Li, ZHANG Wei-hua

Abstract: In order to study the dynamic characteristics of metal helical spring and its dynamic stiffness response to driving frequency, a finite element model of the spring was set up by using FEM, its steady-state response was computed, its frequency-amplitude characteristic curve was analyzed, and an equivalent algorithm of its stiffness was proposed.Computation result shows that the dynamic stiffness of the spring increases with the increase of driving frequency in general tendency, it is minimal and smaller than the static stiffness of the spring corresponding to resonant frequency, however, it is maximal and greater than the static stiffness corresponding to anti-resonant frequency; the stiffness-frequency curves of finite element model and equivalent algorithm almost overlap, so the dynamic characteristic of the spring is remarkable, and the algorithm is feasible.More>

2007, 7(5): 24-27.

FullText HTML (64) PDF (194KB) (284)

Property of self-compacting concrete pavement

Ma Guo-jing, Cai Liang-cai, Wu Yong-gen, Wang Shuo-tai, Huang Can-hua, Su Jing-bin, Dai Nian-wen, Yu Feng-wu

Abstract: In order to improve the performance of self-compacting concrete pavement, the volume percentage of coarse aggregate in self-compacting concrete was increased to 75%, its largest granule diameter was 40 mm, so that the concrete shrinkage was less than 400με; the optimum amount of fly ash and super water reducing agent were added, and the flexural strength formula of sel-compacting pavement concrete was established to make its fluidity, cohesion, flexural strength and impermeability optimum, then, a full-scale slab flexural fatigue test was carried out. Test result shows that the flexural strength test value of self-compacting concrete is 7.0~8.0 MPa, its measure value is 6.5 MPa, and its charge passage is less than 1 000 C in the Cl^- penetrability test; the slump of self-compacting concrete pavement exceeds 160 mm, its fatigue service life increases by 1 time relative to design demand life, and its construction speed increases by 1.5 time. It is obvious that the property of self-compacting concrete pavement is ascendant. 5 tabs, 6 figs, 10 refs.More>

2007, 7(5): 28-32.

FullText HTML (97) PDF (298KB) (209)

Controll index of run-off loss for porous asphalt mixture

YANG Jun, GUO Yong, YIN Chao-en, LIU Qing-quan, CHEN Rong-sheng

Abstract: In order to ascertain the rational control index of run-off loss for porous asphalt mixture, based on the perspective of low run-off loss and adequate strength and durability, optimum asphalt content was selected through laboratory run-off test and Cantabro abrasion test, it was compared with the content selected in current specification, and the influences of different types of fine aggregates were investigated.Analysis result shows that the index in current specification is not more than 0.3%, it is irrational for porous asphalt mixture, so a new index is put forward, it is not more than 0.8%.In the construction of test road, all properties of porous asphalt mixture have little variety, the main properties are superior to that in current specification, so the index is rational, which ensures the quality stability of pavement construction.More>

2007, 7(5): 33-36.

FullText HTML (74) PDF (193KB) (260)

Viscoelastic performance analysis of fiber reinforced asphalt concrete

GUO Nai-sheng, ZHAO Ying-hua

Abstract: In order to investigate the viscoelastic performance of fiber reinforced asphalt concrete, five kinds of cylinder samples were produced, and four samples for each cylinder sample were tested on MTS810 by using uniaxial static compression creep test at 45 ℃.The viscoelastic performance was simulated by using four-unit five-parameter model, its parameters were obtained from the data of the test, and a four-unit five-parameter viscoelastic constitutive model with fiber content was set up.The loading process of the test was simulated by using the new model, and the influence of fiber content on the performance was analyzed.Analysis result shows that the creep response of fiber reinforced asphalt concrete is similar to that of conventional asphalt concrete except the difference of creep deformation, the computation optimal average value of fiber content is 0.18%, its test optimal value is 0.20%, the difference between the values is less, so the new model may be applied in the reference of theory research and material design.More>

2007, 7(5): 37-40.

FullText HTML (125) PDF (198KB) (251)

Nonlinear viscoelastic-elastoplastic constitutive model of permanent deformation for asphalt pavement

PENG Miao-juan, XU Zhi-hong

Abstract: In order to correctly predict the permanent deformation of asphalt pavement, nonlinear viscoelastic finite element method was studied, the finite element method of nonlinear viscoelasticity for generalized Maxwell model was deduced, a nonlinear viscoelastic-elastoplastic constitutive model of permanent deformation for asphalt pavementhen was set up, and the permanent deformation of asphalt pavement was analyzed depending on its material properties, such as elasticity, nonlinear elasticity, plasticity, viscoelasticity and nonlinear viscoelasticity, etc., the permanent deformation of asphalt pavement was simulated by using the model, SHRP and SWK/UN experiment, and the numerical results were compared.Comparison result shows that their relative error are 6.567% and 6.069% respectively, the model is effective.More>

2007, 7(5): 41-47.

FullText HTML (94) PDF (287KB) (692)

Integrative evaluation index system for preventive maintenance timing of asphalt pavement

YAO Yu-ling, LI Xue-hong, ZHANG Bi-chao

Abstract: In order to decide the best timing of preventive maintenance of asphalt pavement, the evaluation indices of service performance and the characters of preventive maintenance were analyzed, an integrative evaluation index system of the timing was set up based on integrating pavement condition index, ride quality index, anti-skid coefficient and asphalt rutting index.The differences of traffic volumes, road environments and compound loads aimed at different roads were considered, the weight coefficients of subentry indices were computed by applying grey relation theory based on the practical status of road.Computation result shows that weight coefficients are 0.27, 0.21, 0.25 and 0.27 respectively, rutting index is a vital controlling target to reflect the nature of young asphalt pavement, and the weight values of subentry indices enable the selection time of the preventive maintenance more pertinent and practicable.More>

2007, 7(5): 48-53.

FullText HTML (71) PDF (281KB) (211)

Service performance prediction model of asphalt pavement with two corrected parameters

ZHANG Zhan-jun, WANG Xiao-feng

Abstract: In order to accurately evaluate the service performance of asphalt pavement, the standard disintegration equation of performance curve of asphalt pavement was studied, the function differences of its shape factor and life factor were analyzed, the shape factor was taken as main dynamic parameter and predicted by adopting modified parameter self-adaptation method, the life factor was taken as a function of traffic load and modified, and a service performance prediction model of asphalt pavement with two corrected parameters was set up.Computation result shows that the prediction value of the model accords with the measure value for the performance, its computation error is minimum, so the prediction precision of model is high.More>

2007, 7(5): 54-57.

FullText HTML (86) PDF (189KB) (197)

Anti-skid property analysis of asphalt runway

SHI Bao-hua, LI Guang-yuan, SHAO Bin, WANG Shi-zhi, CHEN Wei-xing

Abstract: In order to improve the anti-skid property of asphalt runway, ensure the take-off and landing safety of airplane, the anti-skid demand of asphalt runway was analyzed, its friction coefficient, roughness and durability were studied, the criterion of international civil and the anti-skid criterion of asphalt pavement in China were considered, the technical parameters of the pavement were put forward to ensure take-off and landing safety, and the influences of material character, the types, gradations and asphalt contents of asphalt mixtures on the anti-skid property were studied.Analysis result shows that the take-off and landing of airplane are safe when the friction coefficient is 45 measured by using portable pendulum tester, and the texture depth is more than 0.4 mm; rigider broken stone is taken as aggregate, stone matrix asphalt mixture is taken as pavement material, design gradient is rational, pavement firn is cleaned in time, etc, which may improve the anti-skid property of asphalt runway.More>

2007, 7(5): 58-62.

FullText HTML (103) PDF (274KB) (257)

Compactness automatic detecting method of subgrade for intelligent impact roller

ZHANG Hong-chun, DAI Jing-liang, LI Xiao-zhong

Abstract: In order to improve the compactness detecting accuracy of subgrade, Rayleigh wave method was put forward to detect the degree of compaction of subgrade.Rayleigh wave was brought by using dropping hammer, its signal was detected by using detector, and recorded by using earthquake instrument.Processed Rayleigh wave was extracted by using τ-p transform, and its dispersion curve was obtained.The shear velocity of subgrade was invertely computed according to Rayleigh wave, the degree of compaction was computed according to the velocity, its profile diagram was analyzed, and it was detected by using Rayleigh wave method and pouring sand method, and the detecting results were compared.Comparison result shows that the compactness curves almost lap, the maximal absolute error is-0.300%, the maximal relative error is 0.308%, which indicates that the detecting result is credible, and the method is feasible to control impact rolling construction.More>

2007, 7(5): 63-67.

FullText HTML (92) PDF (283KB) (756)

Nonlinear analysis element model of prestressed concrete beam

ZHANG Feng, YE Jian-shu, XU Xiang-feng

Abstract: In order to analyze the mechanics properties of tendon exactly and effectively, simulate normal steel bar, linear tendon and curved tendon in prestressed concrete beam, a nonlinear analysis element model of prestressed concrete beam was presented.In the model, based on finite element method, tendon was simulated by 3-D link bar element of total Lagrangian method, solid degenerated-combined shell element was used to simulate prestressed concrete beam, and the stiffness of link element contributing to concrete element was computed according to the displacement relationship of tendon element and shell element, the action of tendon contributing to the structure was directly reflected inside the element.The simulation result of the destroyed process of prestressed concrete T beam shows that the computation deflection and test deflection in middle span are accordant, and the model can simulate the mechanics properties of tendon.More>

2007, 7(5): 68-72.

FullText HTML (115) PDF (222KB) (281)

Overload capacity analysis of prestressed reinforced concrete beam

ZHAO Wei-guo

Abstract: In order to attested the analysis veracity of ultimate bearing capacity for prestressed concrete beam with finite element method, an loading experiment of ultimate bearing capacity was carried out, a detached finite element model of T beam was designed by using ANSYS finite element program, and the whole processes of T beam's stress and deformation from loading to destructing were analyzed.It is pointed that the variational trends of T beam's load-deflection curves and load-strain curves gained by experiment and the model are accordant, and the curves have good nonlinearity, but the experimental value of ultimate bearing capacity is 9.07 kN·m, the computational value is 12.48 kN·m, their error is appreciably big because of the idealization of the model.Analysis result shows that the nonlinear variations of all variables for prestressed reinforced concrete beam may are simulated by using finite element method in loading process as a whole, and the solution of ultimate bearing capacity is feasible.More>

2007, 7(5): 73-76.

FullText HTML (109) PDF (241KB) (239)

Dynamics analysis model of port group logistics system in Yangtze River Delta

WANG Chuan-xu, CUI Jian-xin

Abstract: In order to realize the coordination development of port group logistics system in Yangtze Rive Delta (YRD), a dynamics model of the system was set up.The effect factors of international container transshipment volume and waterway transportation percentage at Shanghai Port and Ningbo Port were analyzed, the cause-effect relation graphs of the system were constructed, the system was simulated and the rational orientation of port function, the structural optimization of transportation system and transshipment port choice of near sea routes were studied.Simulation result shows that there will be an increase trend of international container transshipment volume in Shanghai Port in 2010, its waterway transportation percentage will be more than 30%, so it should be developed as a container hub port to expand international transshipment business; Taicang Port can be developed as a main transshipment port in near sea routes resulted from possessing the ability of container transshipment.More>

2007, 7(5): 77-83.

FullText HTML (79) PDF (347KB) (207)

Optimization model and algorithm of utilization of arrival and departure tracks in railroad passenger station

LEI Ding-you, WANG Dong, LIU Ming-xiang

Abstract: To improve the automation level and transportation efficiency of passenger station, the technical operation properties of arrival and departure for passenger train were analyzed, and an utilization optimization model of arrival and departure tracks was established.The model had three targets, they were the convenience of riding for passengers, the safe assurance for both train and technical operation, and the effective utilization of technical equipments for train operation, and it was considered to arrange higher rank trains firstly.The model was calculated by applying multiple target programming theory and branch-bound method, and the model and the algorithm were introduced into a large three-line through-type passenger station.Applied result shows that the plan of station tracks is changed obviously, and above 1/3 of train's lines are changed, the effect is ideal.More>

2007, 7(5): 84-87.

FullText HTML (72) PDF (191KB) (838)

Optimization method of configuration of traffic flow guidance information board in urban

MEI Zhen-yu, XIANG Yi-qiang, CHEN Jun, WANG Wei

Abstract: In order to distribute traffic flow guidance information board(TFGIB) in urban properly, the optimization model of configuration of TFGIB was put forward based on the restriction of improving guidance coverage rate and reducing guidance repeat rate.The layout optimization function of TFGIB to maximize the guiding rate of traffic volume was established on the presumption that road network condition and traffic demand area were ensured, the algorithm of the layout function was designed on the basis of genetic algorithm, and the reasonable quantity of TFGIB was confirmed under the restriction.The model was proved through a road network with 15 nodes.It is pointed that when 6 TFGIB are collocated in the net, the guidance repeat rate is 1.000, the guiding coverage rate reaches 0.978, and it is optimal configuration.The result indicates that the method can get the maximum guiding coverage rate under determinate guiding repeat rate, and is an effective method to improve traffic guidance efficiency.More>

2007, 7(5): 88-92.

FullText HTML (83) PDF (252KB) (447)

Bi-level programming model of route traffic information guidance

XU Li-li, SHAO Chun-fu

Abstract: In order to reduce traffic congestion and improve road network efficiency, a bi-level programming model of route traffic information guidance was set up.Managers' optimal function about road network efficiency was optimized by providing different types of information in its upper model, the optimal route choice behavior of driver was described by using utility function in its lower model, its decision-making variables were information types, so that the influence of traffic information on the route choice behavior of driver was introduced into the model.A simple road network was analyzed by using extreme point search method, and the upper function values were computed under different traffic informations.Computation result shows that the fluctuation range of the values is from 8% to 13%, but the congestion vanishing information promulgated from the model in traffic congestion is optimal, the total benefit from qualitative information is greater than that from indication information, so the model is feasible.More>

2007, 7(5): 93-96.

FullText HTML (113) PDF (202KB) (369)

Particle swarm optimization arithmetic of traffic assignment

WANG Su-xin, GAO Li, CUI Xiao-guang, CHEN Xue-mei, GU Li-fang

Abstract: In order to assign traffic volume rationally and expediently, a particle swarm optimization arithmetic (PSOA) of traffic volume multipath assignment was put forward.In the arithmetic, multidimensional particle space was constructed, every dimension was a feasible path, and its value was the assigned traffic volume on corresponding path; particle was united to make traffic volume conservation, and traffic volume multipath assignment was processed by PSOA; particles were circularly evaluated and filtered according to an optimal aim function, so that terminating qualification was satisfied.Computation result shows that the aim function value gained by using the arithmetic is least, the assigned traffic volume of every path is its capacity, the solving process of the arithmetic has optimization direction property and has no limit to net scale, so the arithmetic is feasible and rational.More>

2007, 7(5): 97-100.

FullText HTML (104) PDF (233KB) (828)

Robust optimization model and algorithm of emergency establishment

JIANG Tao, ZHU Jin-fu

Abstract: In order to effectively choose emergency establishment in uncertain case, the weight interval estimation of emergency node was dealt with by using robust optimization method, the minimum weight distance between emergency establishment and emergency node was regarded as aim function, a choice model of emergency establishment in uncertain case was built, a solving arithmetic of the model was put forward, and the robust optimization result and the optimization choice result in certain case were compared.Comparison result shows that compared with the optimization function value, the windage of the optimization solution in certain case is larger than that of the robust optimization solution in uncertain case, so the model availably avoid risk.More>

2007, 7(5): 101-105.

FullText HTML (97) PDF (207KB) (419)

Intelligent selection system of adaptive optimal route based on GIS and grey-fuzzy decision theory

Zhang Fu-ren

Abstract: In order to satisfy drivers' individual interests road traffic, the influence factors of drivers' route selection were analyzed, an optimum index system of route selection was designed, grey-fuzzy decision theory and GIS technique were introduced, an intelligent selection system of adaptive optimal route was put forward, and Web information share method of dynamic data update was adopted to ensure the dynamic property of route selection. Applying result shows that the system can display traffic figures intuitively and visually, driver can well and truly find optimal driving route traffic figures, and the efficiency and dependability ot enhanced. 2 tabs, 7 figs, 15 refs.More>

2007, 7(5): 106-111.

FullText HTML (102) PDF (304KB) (233)

Hybrid-genetic-heuristic algorithm of vehicle routing problem with hard time-windows

HU Da-wei, CHEN Cheng, WANG Lai-jun

Abstract: In order to improve the efficiency of logistics distribution, a mathematic model of vehicle routing problem with pickups, deliveries and hard time-windows was set up, and a hybrid-genetic-heuristic algorithm is designed to solve the model.In the algorithm, improved C-W method and random producing method were used to produce the initial group of solutions to increase its varieties, and the tabu search was used for some better chromosomes of genetic algorithm to avoid local optimization and increase search beginning speed.Simulation result shows that the algorithm has better adaptability, the solution's precision is improved by 11.0% when improved cross operator is used, and the solution's precision is improved by 11.6% when reversed variation tactic is used under big time-windows condition.More>

2007, 7(5): 112-117.

FullText HTML (61) PDF (301KB) (365)

Attribute mathematical recognition model of development level of urban public transportation

WANG Xin-fan

Abstract: In order to rationally evaluate the development level of urban public transportation, its measure index system and grade standard were put forward, and an attribute mathematical recognition model was set up.The weights of the indices were determined by variation coefficient method, and the level was identified by using confidence rule according to the attribute measure values of single index and multiple indices.Evaluation result shows that the development level of public transportation in Qingdao City belongs to fairly high grade, which accords with the result of opinion poll, moreover, the level of its public transportation facilities belongs to high level, the levels of its service and benefit belong to middle level, so the model is feasible.More>

2007, 7(5): 118-122.

FullText HTML (64) PDF (230KB) (242)

Trip speed measurement model of transportation mode under economic restraint condition

Sun Qi-peng

Abstract: In order to reflect accurately the time effect of transportation mode and provide more superior analysis method for each kind of transportation mode, trip speed concept was raised, the constitution of trip time was analyzed from transportation demand, the time interval of vehicle was calculated under economic restraint condition, and a trip speed measurement model of transportation mode was constructed. Analysis result shows that trip speed is a basic index to evaluate the time effect of transportation mode, and trip speed varies dynamically because of economic restriction; in some transport corridor, the key to determine trip speed is the time interval of vehicle, the longer the time is, the smaller the difference between the waiting time saving and transportation time of vehicle, and the lower trip speed is. 11 refs.More>

2007, 7(5): 123-126.

FullText HTML (54) PDF (200KB) (710)

User Center

Journal Info

Collection of Source JournalsMore>

2007 Vol. 7, No. 5

Search Type

Search Journal

LinksMore>