Archive

20 March 2024, Volume 43 Issue 3 Previous Issue   
---
Transportation Infrastructure Engineering
Transportation+Big Data & Artificial Intelligence
Transportation Equipment


For Selected:

Download Citations EndNote Ris BibTeX

Toggle Thumbnails

Transportation Infrastructure Engineering

Select

Bridge Physiognomy and Its Research Progress ZHOU Zhixiang1,2, ZHOU Fengli1,2, CHU Xi1 2024, 43(3): 1-9.  DOI: 10.3969/j.issn.1674-0696.2024.03.01 Abstract ( )   PDF (24800KB) ( )   In order to explore a new method of bridge safety inspection/monitoring that was more effective, economical, convenient and credible, the bridge physiognomy that obtained the recent safety status of the structure according to changes in the appearance of the bridge was proposed, which was inspired by the traditional Chinese medicine concept of “observing, smelling, inquiring and palpation” in diagnosing human health status. The research progress of bridge safety condition inspection/monitoring based on bridge physiognomy for more than 10 years was summarized. The composition theory of the holographic monitoring system for dynamic and static images of bridges based on fixed-point camera flat-turn+vertical-turn shooting, the WWWQ-G bridge safety inspection vehicle based on LIDAR+panoramic digital camera shooting, the system for safety monitoring of conventional span bridges based on ordinary camera shooting and the long-range, global video detection system for tension cable state behavior based on a fixed-point rotating measuring device were introduced. Experimental research cases and practical engineering application cases of each system applied to damage detection of bridge components were also introduced. The method integrating “measuring point sensors+machine vision” to realize the “precise+dense” monitoring of bridge structure status and its application prospects were looking forward to. References | Related Articles | Metrics

Select

Influence of General Aircraft Wheel Load on Mechanical Properties of Airfield Pavement under Uneven Distribution of Road Foundation HUANG Xin1,2, ZHANG Ruoyu1, SUN Bowei1, LI Zhengkai1, ZHAO Fangran1,2 2024, 43(3): 10-16.  DOI: 10.3969/j.issn.1674-0696.2024.03.02 Abstract ( )   PDF (2260KB) ( )   To study the influence of uneven distribution of road foundation in the horizontal direction on the mechanical properties of airport pavement panels, a three-dimensional model of aircraft load-pavement structure-uneven road foundation was established. Numerical simulation methods were used to analyze the influence of changes in the reaction modulus of the foundation top on the flexural tensile stress of the pavement panel under multi-plate collaborative force mode. The influence of changes in the reaction modulus of the foundation top and pavement panel thickness on the mechanical properties of pavement panels and load transfer coefficients of joints under wheel load for general aircraft models (Airbus A320 and Boeing B737-800) was discussed. Meanwhile, the numerical simulation results based on scaled experiments were verified. The research results indicate that: for the A320 aircraft, when the horizontal distribution of the road foundation is uneven, the flexural tensile stress of the concrete slab increases, and the rate of change in the reaction modulus of the foundation top increases from 0% to 65.46%. When the wheel load acts on the edge of the joint plate of the transmission rod, the flexural tensile stress of the pavement slab increases from 4.06 MPa to 5.73 MPa, exceeding the limit value of the ultimate flexural tensile stress. Increasing the slab thickness can effectively improve the range of values for the change rate of the reaction modulus of the foundation top when the rigid pavement panel is under safe stress. The load transfer coefficient of the pavement panel joint increases with the increase of the change rate of the reaction modulus of the foundation top. When the change rate of the reaction modulus of the foundation top increases from 6.84% to 56.30%, the load transfer coefficient of the pavement panel increases by 2.44%. The indoor scaled experiment verifies the influence rule of uneven distribution of road foundation on the load transfer coefficient. It is concluded that the influence of uneven distribution of road foundation in the horizontal direction on the mechanical properties of pavement panels should be fully considered in the design of pavement panels to avoid premature structural damage during service. References | Related Articles | Metrics

Select

Boundary Effect of Concrete Based on Random Aggregate XU Minyao1, WANG Yao1, QIN Yu2,3 2024, 43(3): 17-25.  DOI: 10.3969/j.issn.1674-0696.2024.03.03 Abstract ( )   PDF (11195KB) ( )   In order to study the aggregate boundary effect inside concrete components, the influence rule of real aggregate distribution, shape, length to diameter ratio, particle size, and number of surface edges and corners on the density distribution curve and boundary effects of aggregate was analyzed by image recognition technology and random aggregate modeling technology respectively. The research results show that the aggregate density distribution curve shows a pattern of first rising, then falling, and finally stabilizing or slightly oscillating, and is not affected by the geometric shape of the aggregate. When stable, the corresponding density fraction is slightly higher than the average aggregate density fraction. The peak thickness of aggregate density curve is approximately the minimum particle size of the aggregate, the thickness of the boundary effect layer is about the average particle size of the aggregate, and both gradually increase with the increase of aggregate particle size and length to diameter ratio. Among the geometric characteristic factors of the aggregate, the particle size of aggregate has a significant impact on the density distribution curve, peak thickness, and effect layer thickness, with a stronger degree of influence than other geometric characteristics. References | Related Articles | Metrics

Select

Nonlinear Energy Consumption Analysis of Cracked Slopes Stability Considering Hydraulic Effect LUO Wei1,2, LU Xi1,2, XU Changjie1,2, CHEN Jingyu1,2, TAO Zhi1,2 2024, 43(3): 26-34.  DOI: 10.3969/j.issn.1674-0696.2024.03.04 Abstract ( )   PDF (3777KB) ( )   The existing stability analysis of cracked slopes considering hydraulic effect was mostly based on linear failure criterion, and the failure of rock and soil often presented nonlinear characteristics. Therefore, it was of great significance to carry out nonlinear limit upper bound analysis of cracked slopes stability under the hydraulic effect. Based on the upper bound theorem of limit analysis and strength reduction technology, combined with the “outer tangent method”, the nonlinear failure criterion was introduced to construct the logarithmic spiral failure mode of the slope with vertical cracks at the top of the slope. According to the principle of virtual work, an analytical formula for the safety factor of cracked slopes was derived. Through MATLAB optimization calculation, combined with the slope engineering example, the influence rule of typical factors on the stability of cracked slopes, critical crack and sliding surface position was discussed. The research results show that with the continuous rise of groundwater level h, the slope safety factor decreases continuously, the critical crack depth gradually increases, and the critical crack position gradually shifts towards the top edge of the slope. The nonlinear factor m obviously affects the slope stability, and the safety factor of slope decreases significantly with the increase of nonlinear factor. The use of linear failure criterion will overestimate the influence of groundwater level change on slope stability. With the increase of nonlinear factor, the critical crack depth increases; the crack critical position is farther and farther away from the top edge of the slope, and the volume of the landslide body increases gradually. The distance lm between the crack and slope crest increases with the increase of the nonlinear factor m (when m increases by 0.2, lm increases by about 1 m), and with the increase of the distance between the crack and slope crest, the safety factor of the slope has no obvious change, and the critical crack depth decreases firstly and then tends to be stable. References | Related Articles | Metrics

Select

Characteristics and Causes of Tunnel Thermal Damage in Hydrothermal Activity Zones LIU Xingchen1,2, HUANG Feng1,2, CHEN Shuwang3, WANG Anmin3, YANG Dong2 2024, 43(3): 35-44.  DOI: 10.3969/j.issn.1674-0696.2024.03.05 Abstract ( )   PDF (7694KB) ( )   Abundant geothermal resources in the western part of Yunnan Province present a challenge for partial tunnel projects in dealing with high temperatures when crossing hydrothermal activity zones, seriously affecting construction quality and progress. To reveal the thermal damage characteristics of tunnels through hydrothermal active zones, geological structure survey methods and geochemical analysis of hot springs were employed to study the hydrothermal activity cycle modes in the region by taking Tengyue Tunnel as an example. Based on the heat flux value of the earth, the regional geothermal zone was divided, and the SiO2 geothermometer was utilized to predict tunnel thermal damage. Analysis conclusions indicate that, influenced by geological structures, the heat source of hydrothermal activity in this region originates from volcanic magma. Folds and fractures act as the primary pathways for the circulation and heating of hot water, with water supply replenished by atmospheric rainfall. Water-rock reactions during the circulation, heating, and runoff phases of hot water lead to an increase of Ca2+ in the water. Along the Tengyue Tunnel alignment, the dominant geothermal systems are of medium to low temperature. Heat transfer in this area is mainly through heat conduction, and the proportion of thermal damage along the entire tunnel is as high as 87.3%. References | Related Articles | Metrics

Transportation+Big Data & Artificial Intelligence

Select

Visual Characteristics of the Drivers Using Contraflow Left-Turn Lane Based on Driving Simulation DING Baiqun1, YAN Yanhong1, YANG Liu2, SONG Zilong3 2024, 43(3): 45-53.  DOI: 10.3969/j.issn.1674-0696.2024.03.06 Abstract ( )   PDF (7968KB) ( )   The contraflow left-turn lane is a new traffic organization method to relieve the pressure of left-turn traffic flow. Through the space-time deployment of signal lights, the opposite lane was borrowed as the left-turn waiting zone to improve the traffic capacity of left-turn vehicles in the phase. The driving simulation platform was used to establish the simulation scene of setting contraflow left-turn lane at an urban road intersection. Combined with the eye tracking system, the change of the visual characteristic parameters was obtained during the process of the driver using contraflow left-turn lane. Through pupil changes and eye movement behaviors, the degree of psychological tension of drivers and its association with driving risk were analyzed. The results show that identifying the contraflow left-turn lane signs and three positions such as the opening of the divider, the arrival at the opening of the divider and the arrival at the parking line of the borrowed lane was the concentration point of changes in the driver’s pupil area and continuous fixation time, changes in interest area of fixation and a sudden increase in saccade frequency, which reflects the driver has strong risk perception and psychological load in the corresponding position. There are more short-term fixation behaviors and a large gap in the length of fixation time in using the contraflow left-turn lane, which indicates that the driver pays more attention to the target, absorbs information intensively, and has a significant difference in processing difficulty, requiring high-intensity information processing. The cumulative saccade time accounts for a higher proportion than that of ordinary left turn, and the saccade at small angles below 5 ° is principal, reflecting the complex environmental information and high driving risks in the process of using contraflow left-turn lane. Drivers have a higher demand for search and comparative analysis, and saccade is mainly to capture the target of attention and supplement fixation information. References | Related Articles | Metrics

Select

Drivers Stress Response Behavior in Cognitive Distraction Condition YANG Yanqun1, 2, HUANG Yongjian1, 2, LUO Xiuling1, 2, Said M. EASA2, 3 , ZHENG Xinyi2, 4 2024, 43(3): 54-63.  DOI: 10.3969/j.issn.1674-0696.2024.03.07 Abstract ( )   PDF (4894KB) ( )   40 participants were selected and the 2-back task to induce cognitive distraction was employed. Three stress scenarios, including pedestrian-motorized vehicle, non-motorized vehicle-motorized vehicle and motorized vehicle-motorized vehicle, were established by use of driving simulation system. The experimental studies on the stress response of drivers under normal driving condition and cognitive distraction driving condition in various stress scenarios were carried out. By collecting eye-tracking, EEG, and driving behavior data throughout the experiments, the stress response behavior characteristics of drivers in cognitive distraction condition were analyzed. A set pair analysis (SPA) was conducted on the experimental results to evaluate the safety of driver stress response behavior in different stress scenarios. The results show that the safety of drivers stress response behaviors is reduced by cognitive distraction, and the impact is the most significant in pedestrian stress scenario. References | Related Articles | Metrics

Select

Coordinated Control of Maximum Bandwidth of Arterial Green Waves Considering the Disturbance of Vehicle Flow Speed Distribution XU Jianmin1, LIU Peng1, SHOU Yanfang2, LIN Yongjie1,2, LU Kai1 2024, 43(3): 64-72.  DOI: 10.3969/j.issn.1674-0696.2024.03.08 Abstract ( )   PDF (3761KB) ( )   The speed of urban vehicles is influenced by various factors and exhibits a certain distribution, and a robust arterial coordinated control model should consider vehicle bandwidth requirements at different speeds. To address the problem of poor applicability of traditional coordinated control methods for speed fluctuations on arterial, the spatiotemporal distribution characteristics of vehicle speed on arterial with interference were analyzed. A coordinated control method for the maximum bandwidth of green waves on arterial considering the disturbance of traffic flow velocity distribution was proposed, with the goal of maximizing the recommended speed bandwidth and the expected bandwidth. For an arterial with 4 intersections along Tongji Road in Foshan City, the speed distribution disturbance arterial coordination method can provide a coordination scheme that was more in line with the characteristics of vehicle distribution, which increased the expected bandwidth by about 70% and 14% compared to Maxband and the improved Maxband model. The research results show that the proposed model can reduce the average number of stops by 25%, the average delay by 45%, and the average queue length by 17%. Sensitivity analysis experiments under different speed expectations and variances show that the proposed method can provide a more robust coordinated control scheme for arterial roads. References | Related Articles | Metrics

Select

Design of Basic Demand Width for Non-motorized Vehicle Lanes under Mixed Flows ZHU Shunying1, WANG Yu1, WU Jingan1, CHEN Qiucheng1, WANG Wei2 2024, 43(3): 73-83.  DOI: 10.3969/j.issn.1674-0696.2024.03.09 Abstract ( )   PDF (6726KB) ( )   In order to compensate for the lack of consideration of e-bikes in the design of non-motorized vehicle lanes in existing regulations, it is necessary to study the basic demand width of non-motorized vehicle lanes under saturated mixed flow consisting of human-powered bicycles and e-bicycles. Taking the saturated mixed flow of non-motorized vehicles as the research object, starting from the composition of the physical motion width of non-motorized vehicles, the influencing factors of the physical motion width of non-motorized vehicles were analyzed by constructing a multiple linear regression model, and the categorical independent variables were combined and screened. A linear model of non-motorized vehicle speed and running swing and roadside safety clearance under different combination types was established. The conclusion was drawn that the most unfavorable combination was the one consisting of female, elderly and e-bicycles. The physical motion width of non-motorized vehicles under the most unfavorable combination according to 85% running speed of the non-motorized vehicle lane was determined, and then the basic demand width of the non-motorized vehicle lane was determined. A method of using speed entropy to verify the rationality of basic demand width was proposed from the perspective of stability, in response to the accuracy issue of verifying the rationality of non-motorized vehicle lane width. And multiple non-motorized road sections were tested and verified as examples. The research results show that the width of the basic demand of non-motorized vehicle single lane is 1.65m and 1.5m under the isolation fence and marking line, respectively; and the width of the basic demand of non-motorized vehicle two-lane is 2.9m, 2.8m and 2.65m under the green belt, isolation fence and marking line, respectively. Under the same number of lanes and isolation mode, the wider the lane width, the higher the traffic flow velocity entropy. With the increase of the width of non-motorized lane, taking the width of basic demand as the inflection point, the change amplitude in traffic flow velocity entropy of non-motorized vehicle lanes increases, and the stability becomes worse. References | Related Articles | Metrics

Select

An Identification Model of Entering the Service Area of Agglomerative Hierarchical Clustering Considering the Influence of Traffic Status ZHANG Yu1, ZHANG Tingting2, YAO Chengbei2, CAO Pengchao2 2024, 43(3): 84-91.  DOI: 10.3969/j.issn.1674-0696.2024.03.10 Abstract ( )   PDF (3313KB) ( )   To accurately grasp the characteristics of vehicles entering the expressway service area and improve the operation management level of the service area, the vehicle travel time and speed distribution characteristics of the sections in the service area and adjacent service area were analyzed based on the highway ETC gantry traffic and toll data. Considering the influence of traffic operation state in section, a method for identifying the operation state based on the agglomeration hierarchical clustering and an identification model for judging vehicles entering service area were proposed. Taking the Daguan service area on the G65 Bao-Mao highway as an example, firstly, the speed probability distribution characteristics of vehicles in the service area section under four different operation states were clarified by correlating the traffic states of the upstream and downstream gantry sections. Then, the judging criteria of entering the service area based on the change of traffic density and speed in various operating states were given by clustering algorithm. Finally, the verification and analysis were carried out by using the video bayonet data in the service area. The results show that the identification errors are mainly distributed in the congestion period, and the relative errors of all-day passenger cars and trucks with considering the operation states are 1.5% and 7% respectively, which are 2.9% and 4.1% higher than those without considering the operation states. The effectiveness of the proposed model is verified, which provides a new way to obtain the characteristics of vehicles entering the expressway service area. References | Related Articles | Metrics

Select

Prediction of Logistics Demand in Hub Cities Based on AOA-LSSVM Model XIAO Hong1，2, XIA Ruyu1，2, WANG Xiaokun3，4, YANG Xuefeng5 2024, 43(3): 92-98.  DOI: 10.3969/j.issn.1674-0696.2024.03.11 Abstract ( )   PDF (555KB) ( )   Traditional LSSVM (least squares support vector machine) is difficult to comprehensively reflect the change pattern of logistics demand, which will cause poor prediction performance. Grey correlation analysis (GRA) was used to obtain the main influencing factors of logistics demand, and then the main influencing factors were used as input variables of LSSVM to construct a logistics demand forecasting model. The regularization parameters (γ) and kernel parameters (σ) of LSSVM were iteratively optimized by the Archimedes algorithm (AOA) to reduce the blindness of parameter selection. Thus, an intelligent prediction model AOA-LSSVM was constructed to optimize LSSVM by using the AOA algorithm. After verification, the proposed model can improve prediction accuracy. The proposed AOA-LSSVM model was used to empirically analyze the logistics demand of the important hub cities of the western land and sea new passage such as Chongqing, Chengdu, Guiyang and Nanning. The results show that compared to the LSSVM model, the proposed model can achieve higher prediction accuracy, with a reduction of 1 946.4, 1 206.1, 0.028 4 and 0.039 7 in root mean square error, mean absolute error, and heteroskedasticity-adjusted root mean square error and mean absolute error, respectively. References | Related Articles | Metrics

Select

Optimization of Ticket Allocation and Stopping Plan Combination for Train Cancellation SUN Lishan, LIU Yina, XU Yan, KONG Dewen, SHAO Juan 2024, 43(3): 99-107.  DOI: 10.3969/j.issn.1674-0696.2024.03.12 Abstract ( )   PDF (2825KB) ( )   When trains are canceled due to serious interferences, a large number of passengers will be stranded at the station, while the revenue of the railway company will also be affected. Reasonable ticket allocation is an effective way to solve this kind of problem. Firstly, on the basis of differentially setting the priority of transferring passengers, the optimization model of the combination of ticket allocation and stop plans was constructed and linearized by adding constraints to the inequality system, with the goal of maximizing revenue for railway companies and minimizing deviations from the original timetable. Then, the solver GUROBI was used to solve the above model and analyze the case. The research results show that when a train is canceled due to interferences, the flexible stopping strategy can effectively reduce the number of stranded passengers by more than 19.7%, increase the revenue of the railway company by more than 21.8%, compared to not taking any measures. References | Related Articles | Metrics

Select

Empirical Study on the Relationship between Design Patterns of Regular Bus Stops and Traffic Accidents ZHU Tong1, LIN Zixin1, LIU Jie2, DU Yumeng1, PI Yuxin3 2024, 43(3): 108-115.  DOI: 10.3969/j.issn.1674-0696.2024.03.13 Abstract ( )   PDF (9684KB) ( )   Regular bus stops are an important part of the urban public transport system. Discovering the relationship between station design patterns and operational efficiency was focused on in previous studies, and empirical research on the relationship between design patterns and traffic accidents was lacked. In order to reveal the relationship between design elements and traffic accidents as well as their heterogeneity characteristics, 1176 bus stops of 44 bus lines in a city were taken as the research object, the total number of accidents at the stops in two years was taken as the dependent variable, and design mode characteristics, built environment characteristics, traffic facilities characteristics and other influencing factors were taken as independent variables. Pearson and Spearman correlation coefficient methods were used to screen variables, and on this basis, a geographically weighted negative binomial regression model and a comparison model were constructed. The modeling results show that the performance of the geographically weighted negative binomial regression model is better than that of the comparison model. Further analysis shows that compared with the non-harbor bus stops, the harbor-style bus stops significantly reduce the accident rate; the accident rate of lanes separating bus and non-motorized vehicle is significantly reduced compared with mixed traffic conditions and the station with more lanes has fewer accidents. However, the relationship between other design elements and the number of accidents has not been validated through data validation. In addition, the built environment also has an impact on traffic accidents at stops. The closer to the subway and the CBD, the higher the accident rate. The model also reveals the spatial heterogeneity of the impact relationship. The setting of harbor-style bus stops in areas with relatively small population and inadequate transportation facilities has a more significant effect on reducing accident rates. References | Related Articles | Metrics

Transportation Equipment

Select

Lightweight Design of Metro Vehicle Body Based on Implicit Parameterization Model DU Zhixue, HUA Yang, WEN Xiaoxia, YANG Zhen, HUANG Linkui 2024, 43(3): 116-120.  DOI: 10.3969/j.issn.1674-0696.2024.03.14 Abstract ( )   PDF (1645KB) ( )   In order to quickly realize the conceptual design and performance evaluation of new metro models in the early stage, implicit parameterized modeling of the MP vehicle body of Chongqing Metro Line 6 was carried out by introducing the concept of “analysis driven design”, and 17 main sheet metal parts of the vehicle body were input for experimental design and analysis. 7 sheet metal parts of the vehicle body with relatively high sensitivity of modal and stiffness to mass were selected with the plate thickness as the design variable, and multi-objective lightweight optimization design based on response surface method was carried out. Finally, the stiffness, modal and other performance indicators of the vehicle body had achieved good lightweight effects. The research results show that the implicit parameterized modeling of the vehicle body with the introduction of the concept of “analysis driven design” and the multi-objective lightweight optimization design based on response surface method can be applied to the lightweight design of the vehicle body structure, which has a good guiding significance for engineering. References | Related Articles | Metrics

Select

Fault Diagnosis of Vehicle Suspension High-Frequency Abnormal Vibration Based on Deep Transfer Learning NIU Limin, HU Chao, WAN Lingchu, ZHANG Daiqing 2024, 43(3): 121-127.  DOI: 10.3969/j.issn.1674-0696.2024.03.15 Abstract ( )   PDF (4761KB) ( )   In the fault diagnosis process of vehicle suspension, the deep learning fault diagnosis model has poor training performance when facing a small amount of sample data, resulting in a smaller area under curve (AUC) of the receiver operating characteristic (ROC) curve of the diagnostic model. Empirical mode decomposition (EMD) method was employed to decompose the collected high-frequency vibration signals of vehicle suspensions. According to the energy of each intrinsic mode function (IMF), high-frequency abnormal vibration features were extracted, and the diagnosis model based on deep transfer learning was established. Based on deep convolutional neural network algorithm, the small-sample feature vector information was fault knowledge transferred. The fault diagnosis model was optimized by fine-tuning parameters and updating weights. Experimental results demonstrate that the AUC value of the optimized model is 0.89, and the fault diagnosis results of the proposed model have higher accuracy. References | Related Articles | Metrics

Select

Mechanism of Pore Formation in Laser Welding of 7A52 High-Strength Aluminum Alloy Welds SU Bo1, CHEN Dajiang1, ZHANG Dabin2, HU Jiang1, ZHANG Shuqing1, JIAN Hanqing1 2024, 43(3): 128-134.  DOI: 10.3969/j.issn.1674-0696.2024.03.16 Abstract ( )   PDF (9656KB) ( )   In order to realize the lightweight structure of aerospace equipment and automobile, 7A52 high-strength aluminum alloy plate with continuously varying thickness was therefore used to replace traditional stainless steel and other metals, achieving lightweight from the perspective of structure and material density. When welding aluminum alloy thickened plates with a constant power laser, the amount of heat absorbed per unit volume varied and the keyholes evolved to pores, which affected the quality of the weld seam. The pores in the weld seam were mainly caused by the action of metal vapor on the keyhole wall and the uneven force on the keyhole wall. In order to explore the pore formation mechanism caused by dynamic evolution of the keyhole, the local space of the keyhole wall was divided into a certain number of small cubes, and the energy and forces in a relatively small range were calculated. The effect of force on the keyhole wall surface was analyzed by combining the calculation results with the microscopic inspection results of the weld seam. The weld seam at the thinner end was fully melted, the keyhole wall was subjected to an unbalanced effect of pressure and surface tension generated by metal vapor, resulting in the formation of bubbles in a local area of the keyhole wall, and the thicker end is not fully melted. After the solidification of aluminum alloy weld, the grain growth affected the escape path of the bubbles, and the bubbles eventually evolved into pores. References | Related Articles | Metrics