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15 May 2019, Volume 38 Issue 05 Previous Issue    Next Issue
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Transport+Big Data and Artificial Intelligence
Bridge & Tunnel Engineering
Highway & Railway Engineering
Port & Waterway · Hydraulic & Hydroelectric · Resources & Environment
Traffic & Transportation Engineering
Vehicle &Electromechanical Engineering


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Transport+Big Data and Artificial Intelligence

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Highway Abnormal State Detection Based on Support Vector Machine (SVM) SUN Jingyi1, MOU Ruojin2, SU Xiaobo3 2019, 38(05): 1-7.  DOI: 10.3969/j.issn.1674-0696.2019.05.01 Abstract ( )   PDF (717KB) ( )   Aiming at the abnormal state caused by expressway accidents, the detection program of expressway abnormal states on the basis of support vector machine (SVM) was proposed. Firstly, the vehicle breakdown accident model at one-way three-lane basic section of Kun-Yu Expressway was established by VISSIM simulation software and the abnormal events under different conditions were simulated; furthermore, the influence of abnormal states on the traffic capacity of highway section was analyzed. Then, based on SVM model, the abnormal state detection model of expressway was established, and the difference between unilateral and bilateral input was analyzed. The results of the simulation demonstrate that: the established SVM model for detection of abnormal states has good comprehensive performance; with unilateral input, it can also provide satisfactory detection results of the occurrence of abnormal states. References | Related Articles | Metrics

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Subway IC Card Commuter Crowd Identification Based on GBDT Algorithm WENG Xiaoxiong, LV Panlong 2019, 38(05): 8-12.  DOI: 10.3969/j.issn.1674-0696.2019.05.02 Abstract ( )   PDF (417KB) ( )   With the application and popularization of public transport IC cards, digging commuter users from IC card data is of great significance for taking diversion measures to ease the pressure of morning and evening peaks and optimizing fare formulation at the next stage. Based on the Guangzhou metro data, suitable feature attributes were selected and a commuter crowd recognition method based on Gradient Boosting Decision Tree (GBDT) machine learning algorithm was proposed. Firstly, the data format of the questionnaire was formulated according to five characteristics, including the first and last average card-swiping moment, the first and last average card-swiping time-length, the fluctuation degree of the first and last card-swiping time-length, and the sum of the number of card-swiping at weekdays. Then the GBDT classifier model was trained by using the labeled (commuting/non-commuting) questionnaire data. The accuracy of commuting recognition of the test sample was as high as 94.16%. Finally, the proposed model was used to identify the commuters from the IC card data of Guangzhou Metro. The results show that the number of commuters in Guangzhou Metro card-swiping data is about 1.31 million, accounting for about 32% of the total number of metro card-swiping trips. References | Related Articles | Metrics

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Short-Term Traffic Flow Forecasting Based on Multi-source Traffic Data Fusion LU Baichuan1,2, SHU Qin1, MA Guanglu1 2019, 38(05): 13-19.  DOI: 10.3969/j.issn.1674-0696.2019.05.03 Abstract ( )   PDF (785KB) ( )   Traffic data acquired by different types of traffic detectors contain different traffic information and traffic flow prediction plays an important role in traffic management and control. According to this, multi-source traffic data dynamic weighted fusion and short-term traffic flow forecasting were carried out. On the premise of synthetically analyzing the characteristics of multi-source data and the superiority of data fusion, combining with the advantages of global search of genetic algorithm and adaptive learning of wavelet neural network, a short-term traffic flow forecasting model based on multi-source data fusion and genetic wavelet neural network (GA-WNN) was put forward. The results of case study show that: the traffic data fusion method based on GA-WNN has more advantages than others, and the prediction accuracy of multi-source data fusion is better than that of single data source short-term traffic flow prediction sequence, which provides more precise and comprehensive traffic information for the decision-making of traffic managers and the choice of path for traffic travelers. References | Related Articles | Metrics

Bridge & Tunnel Engineering

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Layout Method of Side-Wall Reflective Material in Highway Tunnel Threshold Zone Based on DIALux LIANG Bo1,2, WEI Qinghua1,3, LI Yanjun4, HE Shiyong1,2 2019, 38(05): 20-26.  DOI: 10.3969/j.issn.1674-0696.2019.05.04 Abstract ( )   PDF (592KB) ( )   Based on the general sky luminance model recommended by the International Lighting Association and the DIALux lighting calculation software, the indoor lighting environment of threshold zone of highway tunnel was simulated. Lighting conditions in threshold zone of highway tunnel of 3 kinds of reflective materials with different reflective nate (0.75,0.80,0.85) under different sky types(sunny day, cloudy day) and lamp layout modes( intermediate and staggered lamp layout) were simulated, with 4 kinds of layout heights (2.0,2.5,3.0,3.5). The influence of different layout methods of reflective materials at the side-wall of the highway tunnel threshold zones on the average brightness and brightness uniformity of road surface in highway tunnel was researched. And actual energy efficiency value was chosen to characterize the influence of laying methods of reflective materials on energy saving effect of highway tunnel lighting. The results show that: the illuminance of road surface in the threshold zone of the highway tunnel increases with the increase of the reflectivity of the side-wall reflecting material and the height of the layout; the average illumination value corresponding to staggered lamp layout is much higher than that corresponding to intermediate lamp layout; the greater the luminance of the natural light outside the tunnel, the more obvious the improvement effect of side-wall reflective material on the lighting quality of the tunnel threshold zone; the energy efficiency ratio per unit length of the reflective material laid on the side-wall of the tunnel is greatly affected by the brightness outside the tunnel. References | Related Articles | Metrics

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Estimation Formula of Vertical Bending Vibration Fundamental Frequency of Self-anchored Single Tower Suspension Bridge GUO Jun, LIU Shenghong, GAO Song, CAI Linzhen 2019, 38(05): 27-32.  DOI: 10.3969/j.issn.1674-0696.2019.05.05 Abstract ( )   PDF (374KB) ( )   In order to calculate the vertical natural frequencies of self-anchored single tower suspension bridge conveniently, the self-anchored single tower suspension bridge with tower-beam support system was taken as the research object. The formula of the vertical bending vibration frequency of the system was deduced by the energy method. Finally, the feasibility of the proposed formula was verified by the case study. The results indicate that the errors between the calculated values of vertical bending fundamental frequencies of the proposed analytical solutions and those of the literature can meet the requirements of the preliminary design stage, and the proposed formula can be used to select reasonable structural calculation parameters in the preliminary conceptual design of the system. References | Related Articles | Metrics

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Influence Analysis of Concrete Strength on Time-Varying Reliability of Widening T-Beam Bridge Based on Support Vector Method WU Xiaoguang1, HE Qilong1, 2, ZHENG Peng1, XIAO Kailong1 2019, 38(05): 33-38.  DOI: 10.3969/j.issn.1674-0696.2019.05.06 Abstract ( )   PDF (520KB) ( )   Based on support vector method, the fitting accuracy of implicit function for the effect function of widening T-beam bridge under the condition of small sample was studied, whose error was less than 5%. The fitting implicit function was used to construct the function of flexural capacity of normal section, and the variation law of time-varying reliability of widening T-beam bridge was analyzed. The research results show that: the prediction results obtained by SVM method are smaller; considering the time-varying effect of concrete strength as well as shrinkage and creep, the reduction of reliability index of beam structure in 70 years is not significant, and it is higher than that of structure without considering time-varying effect. Taking the widening of old beams after 20 years of operation as an example, the reliability index of widening bridge system decreases relatively smoothly in 45 years of operation of new beams, while the reliability index of widening bridge system decreases significantly after 45 years of operation of new beams. References | Related Articles | Metrics

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Pore Structure of Concrete under Action of Vibration Based on Microscope Image Analysis HUANG Weirong1,3, XI Lei2,4, YI Jinming5, LING Yun5 2019, 38(05): 39-44.  DOI: 10.3969/j.issn.1674-0696.2019.05.07 Abstract ( )   PDF (1019KB) ( )   In order to investigate the influence of vibration on the change of pore structure in the process of concrete condensation, the indoor simulation of vehicle-bridge vibration was carried out, and the influence of vibration in different concrete setting time on the mechanical properties of concrete was studied by setting different vibration test parameters. And the change of concrete pore structure after vibration was analyzed by using microscopic image analysis technology. The results show that: the pore area ratio and the number of pores decrease to some extent before applying the vibration with small vibration frequency and amplitude (5Hz, 4mm) during concrete initial setting period, which improves the later strength of concrete. The larger vibration frequency and amplitude (9 Hz, 8 mm) affect the concrete structure, especially from the initial setting period to the final setting period. The larger vibration will destroy the concrete structure, produce certain cracks, increase the number of holes and reduce the strength to a certain extent. There is a good correlation between the strength of concrete and the proportion of the number of holes and the area of holes. The strength of concrete can be reflected by the proportion of the number of holes and the area of holes. References | Related Articles | Metrics

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Lining Stress Caused by Crystal Lization Clogging of Tunnel Drainage Pipe at Different Water Levels GAO Chunjun1，XIANG Lihui2，ZHANG Xuefu1，ZHOU Yuanfu1，LIU Shiyang1 2019, 38(05): 45-51.  DOI: 10.3969/j.issn.1674-0696.2019.05.08 Abstract ( )   PDF (720KB) ( )   In order to study the variation law of lining stress caused by crystallization clogging of tunnel drains at different water levels, the variation law of lining stress under 5 kinds of blocking conditions and 4 kinds of groundwater level conditions was studied by simulating the blockage of drainage pipes with the method of “replacing holes with plates”. The results show that: the variation law of tunnel lining stress under different blocking conditions and different water level conditions is consistent. Under the same degree of blockage, with the increase of the original groundwater level, the tunnel lining stress increases, the maximum principal stress difference between the left and right arch foot of the tunnel increases, and the minimum principal stress difference decreases. Under the same water level condition, 75% of the blockage degree is the turning point of the stress change of tunnel lining. It is concluded that due to the blockage of the drainage pipe, the lining stress increases obviously. When the groundwater level is increased due to the blockage of the drainage system, the lining stress is more unfavorable. Therefore, in the process of tunnel construction, attention should be paid to the effective drainage of drainage system to ensure the safety of lining structure. References | Related Articles | Metrics

Highway & Railway Engineering

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Pavement Performance of Asphalt Mixtures with Economical Low Content Crumb Rubber Modified Asphalt XU Ouming1,2, ZHANG Hong1,2, CAO Zhifei1,2, LI Mingyue1,2, HE Yihua1,2 2019, 38(05): 52-56.  DOI: 10.3969/j.issn.1674-0696.2019.05.09 Abstract ( )   PDF (392KB) ( )   In order to evaluate the effect of low content crumb rubber modified asphalt on the pavement performance of continuous graded asphalt mixtures, the storage stability test, wheel track test, low temperature bending test, moisture susceptibility test and fatigue test were carried out to compare the engineering properties of asphalt and mixtures prepared with base binder, 7% (by mass of asphalt) and 18% ((by mass of asphalt) crumb rubber modified asphalt. The results show that the high temperature stability, low temperature performance and fatigue life of asphalt mixtures modified with 7% crumb rubber are reduced to a certain extent compared with those of mixtures produced with 18% crumb rubber modified asphalt, but they are still significantly improved compared with ordinary asphalt mixtures. In addition, the immersion residual stability of specimens made with low content crumb rubber modified asphalt is higher than that of ordinary asphalt mixture and conventional rubber powder content asphalt mixture, while freeze-thaw splitting ratio is slightly lower than that of ordinary asphalt mixture, but higher than that of conventional rubber powder content asphalt mixture. Meanwhile, the storage stability of rubber asphalt with low rubber powder content is better than that of rubber asphalt with conventional rubber powder content, and when the asphalt content decreases, it has good technical economy. References | Related Articles | Metrics

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Comparison of Performance of Gussasphalt with Different Asphalt Binders WANG Min1，BAO Guangzhi2，LI Lu1，YANG Xinyao2 2019, 38(05): 57-61.  DOI: 10.3969/j.issn.1674-0696.2019.05.10 Abstract ( )   PDF (419KB) ( )   Aiming at the performance differences of polymer composite modified asphalt, lake asphalt compound modified asphalt, and hard modified asphalt for steel bridge deck gussasphalt in China, the basic properties of the three asphalt binders and their fluidity, high temperature stability and fatigue durability were tested and compared, and their performance differences were comprehensively analyzed. The experimental results show that the performance of the gussasphalt is consistent with its binder type. The comprehensive performance of the mixture formed by polymer composite modified asphalt has obvious advantages. The static penetration of the mixture formed by polymer composite modified asphalt is 9.0% and 28.4% lower than that of the other two mixtures when the temperature reaches 70 ℃. Its ultimate strain at low temperature is 22.8% and 60.2% higher than that of lake asphalt composite modified asphalt and hard asphalt modified asphalt mixture respectively. Under 600 με control, the four-point bending fatigue times of polymer composite modified asphalt are more than 1 million times, those of lake asphalt composite modified asphalt are about 325 000 times. Hard asphalt modified asphalt is damaged at the beginning of loading. References | Related Articles | Metrics

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Acceleration Effective Value Fitting Analysis Method of Vibration Compaction of Continuous Testing System ZHU Fei1, JIAN Jieqiang1, LIANG Naixing2 2019, 38(05): 62-65.  DOI: 10.3969/j.issn.1674-0696.2019.05.11 Abstract ( )   PDF (354KB) ( )   In order to continuously detect the compactness of asphalt mixture pavement in real time, the acceleration effective value in the process of vibration compaction was used as the main calculation parameter of the compactness of asphalt pavement. Based on Labview virtual instrument, a continuous testing system for vibration compaction was established, and the data of the measured acceleration in different periods were fitted and analyzed. The compactness data was compared with that obtained from field experiments. The results show that calculation of the effective value of acceleration within 0.4 seconds can be used as the main parameter of the pavement compactness of asphalt mixture, which provides a theoretical and scientific basis for the study of the continuous testing system for mixture vibration compaction. References | Related Articles | Metrics

Port & Waterway · Hydraulic & Hydroelectric · Resources & Environment

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Port Performance Measurement Based on Big Data Analysis ZHANG Qiang1, HE Kai2, WANG Xuefeng1 2019, 38(05): 66-73.  DOI: 10.3969/j.issn.1674-0696.2019.05.12 Abstract ( )   PDF (513KB) ( )   Based on the literature from databases of CNKI and Science Direct, the research trends and development directions of port performance measurement including measurement objects, index system components and evaluation analysis methods at home and abroad during 1984—2017 were reviewed. The research results show that the performance evaluation index system includes traditional performance evaluation index system, input-output evaluation index system and comprehensive performance evaluation index system. The traditional performance evaluation index system is easy to compare and evaluate, but the system is complex; the input-output index system can effectively reflect the relationship between input and output, but the system is relatively simple and lacks comprehensiveness; the comprehensive performance evaluation index system integrates quantitative and qualitative indicators, but the system is too large, and part of the information is difficult to statistics. The evaluation and analysis methods mainly include frontier analysis method, BP neural network method, simulation method and comprehensive analysis method. Among them, DEA model of the frontier analysis method is the most widely used in port performance evaluation. The other three new research methods are the effective supplement and expansion of the traditional frontier analysis method. The research puts forward the direction of development: future research in this field should pay attention to the influence of enterprise management behavior, external institutional environment and other factors on port performance; pay attention to the internal relationship between index system and measurement objects, and the relationship between indicators in the index system; it is also necessary to further develop comprehensive qualitative and quantitative research methods which are practical and operable. References | Related Articles | Metrics

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Calculation Method of Rock Slope Reinforced by Prestressed Anchor Gridiron Beam HOU Junwei1, WU Shuguang2 2019, 38(05): 74-79.  DOI: 10.3969/j.issn.1674-0696.2019.05.13 Abstract ( )   PDF (461KB) ( )   Deficiencies of the commonly-used calculation model of the rock slope reinforced by prestressed anchor gridiron beam were analyzed. The Winkler foundation model was appropriate in calculating internal force of gridiron beam. Based on the regression analysis of test data, regressive formulas to estimate coefficient of subgrade reaction for uniaxial compressive strength of rock under natural condition were given. Based on Winkler foundation model theory, the simplified calculation method of internal force of gridiron beam was obtained through theoretical analysis and calculation. The result indicates that the reaction distribution of prestressed anchor gridiron beam on rock slope is uneven, and the reactions tend to concentrate under the anchor nodes. Interaction of gridiron beam and slope rock mass should be considered when calculating reaction and internal force of gridiron beam. Compared with the conventional design method, the simplified calculation method based on Winkler foundation model theory is more reasonable and economical, in which the cross-section size and reinforcement ratio of gridiron beam are optimized by over 30%, which can provide reference for optimum design of this type of support structure. References | Related Articles | Metrics

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Slope Stability Evaluation Based on Monitoring Information of Horizontal Strain TANG Shengchuan1, HUANG Shiyuan2, ZHOU Yongfeng2 2019, 38(05): 80-85.  DOI: 10.3969/j.issn.1674-0696.2019.05.14 Abstract ( )   PDF (889KB) ( )   Based on the finite element method, 3 numerical models of slopes with different top slope spacing were established. By applying gradually increasing additional loads on the strip footing, displacement and strain responses of the slope were obtained. The failure forms of the slopes were discussed. The relationship between the maximum horizontal strain of the measuring line at different elevations of the slope and the slope stability coefficient was analyzed. Results show that with the gradual increase of base load, the soil horizontal strain also increases gradually; but the maximum horizontal strain and displacement do not appear on the sliding surface. However, the local stress state of soil can be observed by horizontal strain distribution. There is a certain fitting relationship between the slope stability coefficient and the maximum horizontal strain of the measuring line. When the top slope spacing is small, it can be fitted by logarithmic function or power function; when the top slope spacing is large, it can be fitted by linear function. Comparing the correlation coefficients between the maximum horizontal strain and the stability coefficient of different measuring lines in slope models with different top slope spacing, it is found that the best monitoring area is in the middle and upper part of the slope. References | Related Articles | Metrics

Traffic & Transportation Engineering

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Characteristics of Drivers Gaze Shift in Upstream Transition Area of Expressway Maintenance Operation GAO Jianping1, XIE Yichang1, LIU Yuanyuan1, AN Wenjuan2 2019, 38(05): 86-90.  DOI: 10.3969/j.issn.1674-0696.2019.05.15 Abstract ( )   PDF (512KB) ( )   To study the gaze behavior of drivers in the upstream transition zone of highway maintenance operations, real vehicle driving tests were carried out with application of non-contact eye tracker Smart Eye Pro5.7. Eye movement data of 3 tested drivers were monitored and recorded when crossing the upstream transition area of the normal road section and the maintenance operation section. The dynamic cluster algorithm and Markov chain theory were applied to analyze the regularity of drivers gaze shift and the smooth distribution of drivers gaze behavior in traffic environment of common section and upstream transition zone of expressway. Results show that: the front view, far left and far right are the main areas where the drivers get the road information, in which the gaze probability accumulates more than 70 percent; the fixation points have the tendency to transfer between fixation areas taking front view as a center; compared with the normal section, the drivers visual search range is reduced and the probability of gaze return of the main target is increased in upstream transition area; under the influence of the closed lane of maintenance operation, drivers need to pay attention to traffic safety facilities for many times to obtain enough information about the lane channelization and traffic requirements, and at the same time, they need to pay attention to the driving state of vehicles in adjacent lanes. References | Related Articles | Metrics

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Choice Behavior of Bike-Sharing Based on Structural Equation Model CHEN Yanyan, HAO Shiyang, CHEN Ning, LI Jiaxian, LAI Jianhui 2019, 38(05): 91-96.  DOI: 10.3969/j.issn.1674-0696.2019.05.16 Abstract ( )   PDF (542KB) ( )   In order to study the choice behavior of bike-sharing deeply, a bike-sharing travel choice behavior model was established from the perspective of user perception. Taking the bike-sharing users as the research object, a questionnaire survey was conducted to extract the relevant individual characteristics and travel characteristics, and the maximum likelihood estimation method was used to estimate the model. Relative factors that might affect the intention of continuous use of bike-sharing were analyzed quantitatively, and connections between these variables were also explained. The results show that the service quality, attitude and satisfaction of bike-sharing have significant influence on the intention of continuous use, and the service quality also has significant influence on attitude and satisfaction. It has certain reference significance for improving the quality of bike-sharing service, formulating multi-directional green traffic guidance policy, and establishing efficient and fair government management and sustainable mechanism. References | Related Articles | Metrics

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Influence of Bus Dwell Time on Intersection Delay Based on VISSIM Simulation SUN Xianglong1, FENG Shumin2 2019, 38(05): 97-101.  DOI: 10.3969/j.issn.1674-0696.2019.05.17 Abstract ( )   PDF (418KB) ( )   In order to study the impact of bus dwell at the upstream of intersection on vehicle delays, VISSIM simulation was used to study the delay of bus and social vehicles on the primary and secondary intersecting roads, considering the fixed signal timing and bus priority signal timing. The simulation results show that when fixed signals are used at intersections, the delay of social vehicles on primary and secondary roads does not change with the change of bus dwell time. The larger the flow of main roads, the greater the delay of vehicles. When bus signal is preferred, the delay of bus on main roads varies significantly with the change of dwelling time, and the delay of social vehicles is significantly lower than that of fixed signal. The delay of social vehicles on secondary roads increases obviously when the bus stops on the main road for a long time. References | Related Articles | Metrics

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Conditional Value-at-Risk Shortest Path in Stochastic Traffic Network PAN Yiyong, CHEN Lu, DING Yuan 2019, 38(05): 102-107.  DOI: 10.3969/j.issn.1674-0696.2019.05.18 Abstract ( )   PDF (402KB) ( )   In order to study the impact of risk on vehicle routing choice behavior in congested traffic network, the mathematical model of conditional value-at-risk shortest path problem in stochastic traffic network was established through defining the conditional value-at-risk as the objective function of path. The subadditivity of conditional value-at-risk of path was proved, and the conditional value-at-risk shortest path problem was transformed into the conditional value-at-risk shortest path problem based on road segments. A labeling algorithm based on dynamic programming was constructed to solve the problem. Based on the numerical experiments of Sioux Falls network, the calculation results of the conditional value-at-risk shortest path in stochastic traffic network under different risk confidence levels were compared and analyzed. Numerical results show that the conditional value-at-risk shortest path obtaining under different risk confidence levels is different, and the level of risk confidence has a significant impact on the choice of the optimal path. References | Related Articles | Metrics

Vehicle &Electromechanical Engineering

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FEM Analysis and Experimental Research of Vibration Compaction Based on Drucker-Prager Model MA Liying, LI Maoqi, WANG Wei, CAO Yuanwen 2019, 38(05): 108-113.  DOI: 10.3969/j.issn.1674-0696.2019.05.19 Abstract ( )   PDF (795KB) ( )   In order to further study the compaction characteristics of vibratory wheel and the dynamic response relationship between vibratory wheel and soil, the finite element model of “vibratory wheel-soil” was established by ABAQUS. The relationship and the applicable conditions between Mohr-Coulomb model and linear Drucker-Prager model were discussed. The distribution characteristics of soil stress under vibratory wheel and the influence of soil parameters on the dynamic response of vibratory wheel were analyzed, and the model was tested and verified. The results show that: Drucker-Prager model is more suitable for modeling the soil unit, when the friction angle is less than 22°. When the friction angle is more than 22°, the Mohr-Coulomb model should be used to model the soil. The vertical stress of soil is symmetrically distributed along the axis of vibratory wheel, and shifts along the forward direction of vibratory wheel. The vertical stress of soil decreases sharply with the increase of depth of soil. Under the reasonable working conditions of the vibratory roller, with the working parameters unchanged, the effective value of the vertical acceleration of the vibrating wheel of a vibrating roller increases with the number of compaction cycles. The proposed model is basically correct, and the regression equation between the compaction degree and the effective value of acceleration is obtained, which provides the idea for the new compaction degree monitoring system. References | Related Articles | Metrics

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Stiffness Optimization of Powertrain Mounting System LIU Shaohua1, SHAO Tingting1, LU Jilei2 2019, 38(05): 114-117.  DOI: 10.3969/j.issn.1674-0696.2019.05.20 Abstract ( )   PDF (474KB) ( )   The powertrain mounting system has an important influence on the performance of the NVH. A fifteen degree of freedom model was established on the basis of the powertrain mounting system selected for a certain type of vehicle. With the help of ADAMS simulation software, the decoupling analysis of the proposed mounting system was carried out. The simulation results show that the decoupling degree of the mounting system is not high in the first and the six order, and it needs to be optimized. The bushing stiffness and elastic center at four mounting points of the engine were taken as design variables, and the first and the six order decoupling degrees were taken as the objective functions to optimize the simulation. The results after optimization show that: the decoupling degree of the first six orders of the system is improved, and the first order and the sixth order are increased by 21.87% and 4.56%, respectively. References | Related Articles | Metrics

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Economic Model and Evaluation of Engineering Retread Tires Based on Life Cycle Theory WANG Qiang1,2, QI Xiaojie1, WANG Yunlong1, JIANG Li1, WANG Guotian1 2019, 38(05): 118-122.  DOI: 10.3969/j.issn.1674-0696.2019.05.21 Abstract ( )   PDF (370KB) ( )   On the basis of determining the life cycle system of the engineering retread tires, the cost analysis model, the profit analysis model, and the environmental cost-environmental profit analysis model based on the life cycle theory were constructed, and the economic evaluation indicators were put forward. The cost and profit of engineering tires was analyzed and evaluated, in the production stage, transportation stage, use stage and reuse stage (ordinary retread, graphene enhanced retread, mechanical crushing, cryogenic crushing, combustion decomposition and combustion power generation, etc.). The results show that the cost of the engineering tire is the highest in the production stage and the lowest in the transportation stage. The profit-cost ratio of reused engineering tires is the highest using graphene enhanced retread method, followed by ordinary retread method, and the lowest using combustion power generation method. References | Related Articles | Metrics