交通运输工程学报

Fatigue damage characteristics of rib-to-deck weld root on orthotropic steel bridge deck

ZHOU Xu-hong, PENG Qian, QIN Feng-jiang, DI Jin

Abstract: For the problems that the root-deck fatigue cracks of orthotropic steel decks with closed ribs located inside ribs were invisible and greatly harmful, the deck root welding fatigue details were divided into RD details (rib-to-deck details) and RDF details (rib-to-deck details crossing floor beams) according to the connected locations of longitudinal ribs and deck, and the finite element method was applied to study the stress influence surfaces of two fatigue details.The transverse frequency distribution of wheelmark, multiaxial loads and pavement-deck interactionwere considered, and the damage characteristics of two fatigue details were analyzed.Analysis result shows that the target details are in the most unfavorable condition when the wheel is right above each of them.In the longitudinal direction, the stress is relatively higher when the distances of wheel load and target details are no more than 0.6 m.In the transverse direction, the wheel load influence ranges of two details are within 1.0 m.When the transverse distribution of wheelmark is considered, the transverse reduction coefficients of equivalent stress ranges of two details in simplified computation are 0.92 and 0.96, respectively.Under the dual-axle and tri-axle loads, the damages of RD details are 2.10 times and 3.21 times of the damage under single-axle load, respectively.It is unsafe to compute the damage by approximately adding the damage of each axis load, so it is suggested to consider vehicle type while assessing the fatigue life.The stress range of each detail obviously reduces when the pavement-deck interaction is considered, and the change will increase with the increase of elastic modulus of pavement.The stress range of deck with 12 mm thickness considering pavement is almost equal to the range of bare deck with 16 mm thickness at the welding root.For the simplified diffusion model of pavement with 45°dispersion angle, when the thickness of deck is no less than 16 mm, the stress range is simultaneously less than the range of soild model considering the contributions of diffusion and stiffness of pavement, and the difference increases with the increase of thickness of deck, so it is slightly risky to simplify the dispersion effect of pavement without considering its scope of application.When the thickness of deck is 18 mm and the contribution of pavement is considered, the fatigue lifes of two details can meet the design requirement of service life, and RDF details are about 67% of RD details in fatigue life.More>

2018, 18(1): 1-12. doi: 10.19818/j.cnki.1671-1637.2018.01.001

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Review of ultra-high performance concrete shrinkage

CHEN Bao-chun, LI Cong, HUANG Wei, AN Ming-zhe, HAN Song, DING Qing-jun

Abstract: The shrinkage characteristics of ultra-high performance concrete (UHPC) were analyzed.The general rules of UHPC contraction with time were introduced.The influences of material composition, curing regime, internal temperature and internal humidity on UHPC shrinkage were summarized.Research result indicates that the shrinkage of UHPC develops rapidly at 0-7 d, accounting for 61.3%-86.5% of total shrinkage, develops slowly from 7 dto28 d, accounting for 13.5%-27.9%, and becomes steady after 28 d.Autogenic shrinkage is the main cause of early cracking of UHPC, and accounts for 78.6%-90.0% of total shrinkage.In term of the start point about shrinkage test, the initial time of test is 1 d (24 h) after specimen forming, and the termination time is 90 dor 120 d.In term of structural design, it may refer to the values (500-800με) in various countries' standards, and not to consider the residualshrinkage after heat curing.In term of shrinkage prediction models, the norms of all countries have not been uniformed yet, it can only refer to the existing models, and the shrinkage prediction models should be improved and revised.In term of component research, the quantitative impacts of types and contents of fibers and mineral admixtures on the shrinkage are research emphasis, the effect of each component on the shrinkage is different, and the evaluation indexes are relatively simple and should be combined with structural applications, preparation techniques and construction process to comprehensively evaluate the shrinkage.In term of the internal temperature and humidity fields, the research mainly concentrates on normal concretes, high-strength and high-performance concretes after 28 d, and it should be more in-depth study on the early internal temperature and humidity fields of UHPC with the large content of cementitious material, obvious difference of components, and high content of active mineral admixture.In term of reducing shrinkage, internal curing, expansive agent, shrinkage-reducing agent, coarse aggregate, and other measures are applied.Therefore, it should optimize the ratio of UHPC, rationalize the use of admixture, and adopt proper curing system and other measures to reduce the shrinkage of UHPC, but not to reduce its mechanical properties.More>

2018, 18(1): 13-28. doi: 10.19818/j.cnki.1671-1637.2018.01.002

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Ultimate flexural strength and ductility of steel and concrete composite girder with circle tubular flange

ZHU Jing-wei, WANG Chun-sheng, ZHAI Xiao-liang, LIU Hao, CUI Zhi-qiang

Abstract: In order to investigate the flexural performance of steel and concrete composite girders with circle tubular flange, the flexural failure tests of three composite girders with circle tubular flange were carried out by static loading, and the failure processes and failure characteristics of test girders were obtained.Based on considering the damage plasticity constitution of concrete, the slippages and fractures of studs, the nonlinear finite element models of composite girders wereconducted and validated by using experimental results.The width of lower flange of steel girder, the thickness of concrete slab and the diameter of tube were taken as main structural parameters, and the mechanical properties of 48 numerical model composite girders with circle tubular flange based on orthogonal design were calculated.According to the flexural behaviors of test girders and numerical model girders, the ultimate flexural bearing capacity formulas of composite girders with circle tubular flange were established based on the simplified plastic theory.By the numerical calculation results regression, the empirical expression of displacement ductile coefficient for composite girders was proposed.Computation result shows that the strength and deflection ratios of the numerical models to the test girders are 0.99-1.03 and 0.87-1.09, separately, so the moment-deflection computation curves are in good agreement with the experimental curves, which demonstrates that the whole processes of flexural behaviors for composite girders with circle tubular flange can be simulated accurately by using the numerical models.The ultimate flexural strength of composite girder with circle tubular flange increases with the increase of lower flange width of steel girder and the thickness of concrete slab, and changes little with the diameter of tube.The displacement ductile coefficient increases linearly with the increase of thickness of concrete slab and diameter square of tube, whereas reduces linearly with the increase of lower flange width of steel girder.For the model girders with different plasticity statuses, the displacement ductile coefficients are 3.16-7.19, which indicates good ductility.The ratios of ultimate flexural strengths computed by using the proposed simplified formulas and the numerical model composite girders are 0.91-1.09, and the average ratio is 0.98, so the computation result by using the formulas is accurate.To ensure the appropriate ductility of composite girder with circle tubular flange, it is suggested that the displacement ductile coefficient is greater than 3.5.More>

2018, 18(1): 29-41. doi: 10.19818/j.cnki.1671-1637.2018.01.003

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Seismic responses of CRTSⅡ track system on bridge under complex geography conditions

YAN Bin, HUANG Jie, LIU Shi, LOU Ping

Abstract: To study the effect of complex geographies on the seismic responses of CRTS II track system on bridge, the 16-32 msimply supported bridge on the Shanghai-Kunming High-Speed Railway was taken as an example, the nonlinear dynamics simulation model of multispan simply supported bridge and double CRTS Ⅱ track system was established based on considering rail, fastener, track plate, mortar layer, base plate, sliding layer, bridge, consolidation mechanism, terminal spine, check block and other parts, and the longitudinal force distribution characteristicsof CRTS II track system on the bridge were studied.Four kinds of typical geography conditions were set to study the seismic response rules of CRTS Ⅱ track system on the bridge.Research result shows that compared with the non-longitudinal continuous track structures, the maximum track stress of CRTS Ⅱtrack structure on the bridge is relatively smaller and about 138.8 MPa, and its stress envelope curve is antisymmetric and more smooth.Track plate and base plate together bear longitudinal forces, and their maximum values are near the bridge abutment and are25.2 MPa and 27.1 MPa, respectively, which can result in cracking during the earthquake.The terminal spine bears huge longitudinal force that can reach 14-20 MN.During earthquake, a greatly relative displacement more than 24 mm occurs between base plate and bridge deck, which has the effect of seismic isolation and energy consumption.The geography conditions have 30%influence on the longitudinal stresses of rail, track plate and base plate, while have greater influence on the shear force at the pier bottom.The shear force at the pier bottom increases 4 times where the terrain (pier height) mutates.The lateral deformation of sliding layer near the abutment is larger and can reach to 2.7 mm.With the increase of pier height, the longitudinal, lateral and vertical deformations of fastener and sliding layer increase.The sliding layer generally has larger vertical deformation that can reach 43.5 mm near the abutment.In the earthquake, there is frequent collision between check block and base plate, and the collision force near the abutment is more than 38 MPa that can cause the damage of check block.More>

2018, 18(1): 42-50. doi: 10.19818/j.cnki.1671-1637.2018.01.004

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Elastic-plastic solutions of bilinear strain-hardening tunnel and pile cavity based on tri-shear failure criterion

ZHAO Jun-hai, ZHANG Lei, ZHANG Chang-guang, CAO Xue-ye

Abstract: Tunnel and pile cavity were simplified as thick-walled cylinders, the effects of strain hardening and intermediate principal stress were considered, the elastic-plastic limit solution of thick-walled cylinder under uniform internal and external pressures was deduced based on the trishear failure criterion and the bilinear strain-hardening model, the relationship of internal pressure and elastic-plastic radius under constant external pressure was given, and the effects of many parameters on the limit solution of thick-walled cylinder were discussed, including strengthening modulus, radius ratio, intermediate principal stress and material strength heterogeneity of tension and compression.Research result shows that the proposed solution can overcome the deficiencies of material strength heterogeneity of tension and compression ignored by Tresca and Mises yield criteria, the intermediate principal stress ignored by Tresca and MohrCoulomb yield criteria, as well as the abrupt changing phenomenon of slip plane in twin shearstrength theory.The limit solution increases with the radius ratio and the intermediate principal stress coefficient, but decreases with the tension-compression strength ratio.The effect of external pressure on the limit internal pressure decreases with the tension-compression strength ratio.Compared with no considering strengthening modulus, when the strengthening modulus is0.1 and the radius ratio is 2, the plastic limit internal pressure increases by more than 10%.When the radius ratio increases to 4, the plastic limit internal pressure increases by more than38%, so the strengthening effect is more obvious.Obviously, for the material with strain hardening effect, the result analyzed by the bilinear strain-hardening model is closer to the engineering practices.When the intermediate principal stress and the strain hardening are not considered, the differences of limit expansion soil pressures calculated by the proposed solution are within 0.02% compared with the values calculated by the Vesic theory.However, when the intermediate principal stress and the strain hardening are considered and the ratio of the plastic zone radius to the inner radius is 10, the limit solutions are respectively 1.06 times and1.81 times the values calculated by the Vesic theory.As a result, the limit expansion pressure based on the Vesic theory is too conservative.More>

2018, 18(1): 51-60. doi: 10.19818/j.cnki.1671-1637.2018.01.005

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Stability of lime-fly ash loess under action of water immersion

ZHANG Zhi-quan, JING Yan-lin, KONG De-quan, ZHAO Jie

Abstract: The strength tests and mercury injection tests on lime-fly ash loess under 2 actions of water immersion with different times of wetting-drying cycle and different saturation times were conducted, and the stability of lime-fly ash loess was analyzed.Analysis result shows that the unconfined compressive strength of lime-fly ash loess at 7 dis higher and about 1.33 MPa.With the increase of the times of wetting-drying cycle, the strength of lime-fly ash loess decays.After2 times of wetting-drying cycle, the strength falls drastically and tends to be stable.After10 times of wetting-drying cycle, the unconfined compressive strength and shear strength of limefly ash loess decrease by 42.8% and 47.4%, respectively.With the increase of the times of drying-wetting cycle, the total void volume of lime-fly ash loess increases linearly.After 10 times of wetting-drying cycle, the total pore volume of lime-fly ash loess increases from 0.200 1 mL·g^-1 to 0.238 3 mL·g^-1, which is equivalent to 19%.During drying-wetting cycle, the pore diameter variation rules are different, the large void volume increases linearly, but the small and micro void volumes do not change basically.With the increase of saturation time, the strength of limefly ash loess decays, decreases significantly after 2 dwater immersion, and gradually stabilizes with the continuous immersion.After 4 dwater immersion, the unconfined compressive strength and shear strength of lime-fly ash loess decrease by 33.6% and 54.7%, respectively.The result indicates that when the contents of lime and fly ash are less, the water can weaken the strength of lime-fly ash loess obviously, the action of water immersion can lead to the decrease of strength, the dry density slightly decreases, and the total pore volume increases.But compared with the unmodified loess, the lime-fly ash loess has higher strength and better water stability, and can be used as road subgrade in loess area.More>

2018, 18(1): 61-70. doi: 10.19818/j.cnki.1671-1637.2018.01.006

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Fatigue failure mechanism and improvement method of safety suspender mounting base of speed-up passenger car bogie

LIAN Qing-lin, LIU Zhi-ming, WANG Wen-jing

Abstract: The fatigue crack characteristics in the vicinity of bolt hole on the safety suspender mounting base of speed-up passenger car bogie were analyzed.A hypothesis was proposed that the structural vibration fatigue caused by resonant phenomena is the most important reason of the crack initiation in the position.The first 1-10 order modes' vibration shapes of safety suspender were obtained by using finite element simulation.The frequency of each order mode was analyzed.Field tests on acceleration and dynamic stress were conducted.The equivalent stresses and accelerations as well as their dominant frequencies were obtained.Field test results were compared and analyzed with FE simulation result.Based on the command of failure mechanism of safety suspender mounting base, the structure of safety suspender and the way of connection were optimized by using structure improvement and connection adjustment.Field line tests were applied to the new structures, and the safety and economy were evaluated.Analysis result showsthat because of the influence of track line conditions of normal passenger car, the vibration frequency of safety suspender, which is 91.78 Hz for acceleration and 91 Hz for dynamic stress, is very similar to the fourth order mode frequency (95.79 Hz) calculated by FE simulation, so that the resonance occurs.The longitudinal acceleration power spectral density of safety suspender is much higher than its lateral value and vertical value, which corresponds to the running direction of train, so crack initiation in the vicinity of safety suspender mounting base is resulted from vibration fatigue.The equivalent stress amplitudes can reduce effectively while placing 5 mm shims on both sides of bolt hole and altering the steel plate bending structure with flexible wire rope structure, and less fatigue damage accumulates.The improved safety suspender can meet the application requirement of running 12 million kilometers, and economic benefit is better.More>

2018, 18(1): 71-78. doi: 10.19818/j.cnki.1671-1637.2018.01.007

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Stress response and fatigue damage assessment of high-speed train gearbox

LI Guang-quan, LIU Zhi-ming, GUO Ru-bing, XU Ning

Abstract: A high-speed train line test was carried out, the GPS signal and mechanical characteristics of gearbox structure were researched, and the stress-time history curves under torque load and vibration load were obtained.The stress response characteristics of gearbox under the action of torque load and vibration load were analyzed, and the stress spectrum was compiled.The influencing parameter of fatigue damage was used to reflect the effect degrees of torque load and vibration load on the fatigue damage of gearbox.Research result shows that under torque load, the alternative change between train traction and braking can cause greater stress response of gearbox, and the maximum stress amplitude is 25.80 MPa.In the braking condition, the stress of gearbox fluctuates like ladder wave.The frequency of high stress amplitude at the end of gearbox hanger seat is higher at low speed than at high speed, and the influencing parameter of fatigue damage declines by 60.0% from 0.20 to 0.08.Under vibration load, when train speed drops from 350 km·h^-1 to 200 km·h^-1, the stress response strength at the end of gearbox hanger seat declines by 53.4% from 2.08 MPa to 0.97 MPa.The gearboxstress amplitude is lower at the front of train than at the tail at the same speed level.When the train transforms from traction state to inert operation, the stress response strength decreases by70.6%from 3.4 MPa to 1.0 MPa.When the train transforms from low speed to high speed, the influencing parameter of fatigue damage at the end of gearbox under vibration condition increases by 27.9 times from 0.009 to 0.260.More>

2018, 18(1): 79-88. doi: 10.19818/j.cnki.1671-1637.2018.01.008

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Influence of dynamics effect on safety of cable in wreck up-righting project

JIA De-jun, LI Fan-chun

Abstract: In order to study the influence of dynamics effect on the safety of wreck up-righting project, cable tension was introduced as the evaluation index of the safety.Four hypotheses were made, including that the hanging point of lifting arm was be fixed, the seabed in research area was rigid, the effect of superstructure was ignored, and restoring force and external loads were only considered in establishing the quasi-static model of up-righting wreck.Cable tensions, ship weight, cable stiffness, cable-winded velocity and wave loads were taken as variables.Cable tensions in wreck up-righting project were calculated by using the time-domain analysis method while considering dynamics effect.Based on the maximum calculated cable tensions, the influences of ship weight, cable stiffness, cable-winded velocity and wave loads on cable tensions were analyzed, and the safety of up-righting project was evaluated.Calculation result shows that in wreck up-righting project, the maximum cable tension increases when ship weight, cable stiffness and cable-winded velocity increase, and has linear relationship with cable-winded velocity, approximate linear relationship with ship weight, and nonlinear relationship with cable stiffness.When cable-winded velocity increases from 0.001 m·s^-1 to 0.020 m·s^-1, theincrement of the maximum cable tension increases by 22 times, so the dynamics effect cannot be ignored in the safety evaluation of wreck up-righting project.More>

2018, 18(1): 89-100. doi: 10.19818/j.cnki.1671-1637.2018.01.009

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Influence of parameters of magnetorheological damper on vibration attenuation effect of seat suspension system

HU Guo-liang, LIU Qian-jie, LI Gang, XU Ming

Abstract: The relationships among the output damping force and the structural dimension parameters (cylinder inner diameter, piston diameter, piston rod diameter, effective piston length), coil turn, and apparent viscosity of magnetorheological fluid of magnetorheological damper (MRD) were obtained based on the Bingham constitutive mechanical model.The effects of the six parameters of MRD on the output damping force and the dynamic range were analyzed by using the obtained mechanical model.A semi-active seat suspension system model based on MRD was established, and the RMSs of driver acceleration and dynamic displacement of seat cushion were used as the evaluation indexes of vibration attenuation effect, and the RMS of percentage-based slope was put forward to evaluate the influence degrees of MRD parameters.The influences of the six parameters of MRD on the vibration attenuation effect were investigated, and the influence of MRD wear on the vibration attenuation effect was analyzed simultaneously by using the Bingham constitutive inverse mechanical model.Analysis resultshows that the influence factors of piston diameter on the driver acceleration and the dynamic displacement of seat cushion are 4.83 and 5.46, respectively.The influence factors of cylinder inner diameter are 4.45 and 4.75, respectively.The influence factors of coil turn are 0.61 and0.67, respectively.The influence factors of piston rod diameter are 0.53 and 0.59, respectively.The influence factors of effective piston length are 0.51 and 0.56, respectively.So piston diameter has the most important influence on the vibration attenuation effect, the second is cylinder inner diameter, and then followed by coil turn, piston rod diameter and effective piston length.However, the apparent viscosity of magnetorheological fluid has little influence on the vibration attenuation effect.Besides, in order to obtain a better vibration attenuation effect, the maximal output damping force and dynamic range of MRD should be larger enough.More>

2018, 18(1): 101-110. doi: 10.19818/j.cnki.1671-1637.2018.01.010

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Review on location-routing problem

HU Da-wei, CHEN Xi-qiong, GAO Yang

Abstract: Location-routing problem (LRP) was studied.The models of LRP and LRP extensions at home and abroad were summarized.The applicability of solving methods to LRP models were compared.The nodes-distributions and data scale of testing instances were analyzed.The main future research directions of LRP were proposed.Analysis result shows that the research of LRP models extends from the mostly simplified problem of basic logistics network (the capacitated LRP, CLRP) to multi-direction: including LRP extensions based on complicated networks such as, multi-objective LRP based on specific network systems, LRP with simultaneous pickup and delivery, LRP with cross-docking center, two-echelon LRP, location arc routing problems, truckand trailer routing problem and Planar LRP; and extensions based on uncertainties such as, LRP with fuzzy factors, multi-period LRP; meanwhile developing to more practical problems such as highly integrated LRPs, LRP with uncertainties and dynamic LRPs.On algorithms for LRPs, the exact algorithm can only be used to solve the small-scale problem.So the main researches on algorithms are gradually turned from intelligent algorithms in earlier times to metaheuristic algorithms, algorithms based on various neighborhood search optimization methods and hybrid algorithms.These algorithms which are designed based on the specific problems have good performance, especially the adaptive large neighbors search with various destruction factors and repair factors obtained better solutions on large-scale instances, and it is highly reusable.Test instances frequently used in the literature reflect that nodes in the instances follow uniform distribution, heap distribution and mix distribution.The instances specifically adapted to 2 ELRP, LRPSPD and other LRP extensions are gradually generated.Finally, the main direction of future research on LRP extensions is put forward according to the change and demand of logistics market environment, which include extensions of multi-echelon LRP such as 2 E-LRPSPD and 2 ELRP with inventory, planar LRP, priority based LRP with profits or competition, LRP with mixed uncertainty.Future directions on solving methods are also proposed: further exploration of exact algorithms for medium and large scale problems, the designation of hybrid heuristic algorithms with higher accuracy and efficiency, and the application of approximate algorithm for solving the optimal solutions of LRP and LRP extensions.More>

2018, 18(1): 111-129. doi: 10.19818/j.cnki.1671-1637.2018.01.011

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Integrate opitmization model of operation schedule for metro express/local train

SHI Jun-gang, YANG Jing, ZHOU Feng, XU Rui-hua

Abstract: In order to optimize express/local train operation schedule of metro, an integrated calculation optimization model of train operation scheme, stop schedule plan and timetable was established.The characteristics of train stop, interstation running, express/local train operation organization and passenger travelling were analysed.The constraint conditions of operation plan of express/local train were built, and an objective function of comprehensive coordination optimization of train operation time and transportation cost was designed.The integrated operation plan optimization model of metro express/local train was established, and a two-stage approximate algorithm was designed to solve the model.At the first stage, according to the maximum waiting time that passengers can endure, the number of local trains can be calculated.The local trains were required to evenly depart in the considered time horizon, then the initialtimetable was reasonably adjusted.At the second stage, the express/local train operation schedule was solved by using CPLEX solver.Aiming at Shanghai Metro Line 16, the express/local train operation schedule experiment was worked out during morning peak 7:00-9:00 in down direction.Experimental result shows that 30 trains operate in the express/local train operation schedule, including 11 express trains and 19 local trains.9 times of overtaking and 87 times of skip-stopping are accomplished, the maximum saving time of express train during whole journey is 628 s, reduces about 4.1%, and the total travel time saves 4 450 s.The ratio of express/local trains are flexibly assigned between 1∶1-1∶2 according to the passenger demands.The stopping scheme of express trains are flexibly assigned according to the inflow and outflow demands of passenger at each station, and their stopping schemes are not constant.The computing time turns to be much longer as the train scale gets larger, so a more effective algorithm need to be designed when the scale increases to a certain extent.More>

2018, 18(1): 130-138. doi: 10.19818/j.cnki.1671-1637.2018.01.012

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Distribution characteristics of traffic crash data of freeway based on statistics and hypothesis test

MENG Xiang-hai, TAN Wei, HUO Xiao-yan

Abstract: In order to analyze the distribution characteristics of traffic crash data on the basic sections of freeway, traffic crash number, fatal and injury crash number, death and injury numbers of traffic crash were taken as discrete random variables, and crash interval time and average annual crash number per kilometer were taken as continuous random variables.For discrete crash data, the sections of freeway were divided by using equally divided method, dynamic clustering method and sliding window method, and crash data were fitted by using Poisson distribution, negative binomial distribution, zero-inflated Poisson distribution and zeroinflated negative binomial distribution.For continuous crash data, the sections were divided based on the toll intervals, crash data were fitted by using normal distribution and negativeexponential distribution.The goodness-of-fit tests of various fitting results were performed by using Pearson's square.Analysis result shows that in all sections, crash numbers are subject to negative binomial distribution, and in some cases, obey negative binomial distribution and Poisson distribution at the same time.Fatal and injury crash number and death number of traffic crash mainly obey zero-inflated Poisson distribution or zero-inflated negative binomial distribution.The probabilities of goodness-of-fit test are all greater than 0.05.Average annual crash number per kilometer is more subject to normal distribution, while crash interval time mainly obeys negative exponential distribution, and the probabilities of goodness-of-fit test are also greater than 0.05.The statistical distribution characteristic of traffic crash data is one of the prerequisites for establishing crash prediction model and the identification of crash black spots, and crash interval time can be used as the measurement indicator of safety reliability.More>

2018, 18(1): 139-149. doi: 10.19818/j.cnki.1671-1637.2018.01.013

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Public bicycle usage modeling based on urban land use

TANG Lu-liang, CHEN Xi, YANG Xue, ZHANG Xia, LI Qing-quan

Abstract: The public bicycle travel pattern was divided into three phases, namely going to a station, riding after renting, and leaving after returning.The influence of urban land use on public bicycle usage was investigated for each phase.For the first and third phases, the points of interst were used to measure the type of urban land use surrounding public bicycle station.By introducing time satisfaction function, a modeling method of the prediction of public bicycle demand and attraction was proposed based on multiple regression analysis.For the second phase, six influence factors of public bicycle usage related to urban land use were established, including the bicycle demand of origin station, the density of origin station, the remoteness of origin station, the attraction of destination station, the distance between origin and destination station, and the land use difference between origin and destination station.961 865 and 1 185 816 records of public bicycle usage respectively from New York and Shanghai were analyzed by using multipleregression analysis.Analysis result indicates that for the records of New York and Shanghai, the modeling method yields higher determination coefficients (0.738 and 0.607) than the traditional method (0.581 and 0.474) when the number of land use factors is invariable.All of six proposed factors have significant influence on the traffic volumes between the stations in bicycle traffic volume model, and the adjusted determination coefficient is 0.487.In conclusion, the modeling method can measure the influence of urban land use on the public bicycle usage more feasibly, and it provides a more accurate model of trip demand at stations, traffic volume between stations, and attraction of stations for public bicycle trips.More>

2018, 18(1): 150-158. doi: 10.19818/j.cnki.1671-1637.2018.01.014

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