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As China’s socio-economic progress accelerates, residents’ mobility preferences are growing more varied. Owing to their eco-friendliness, high capacity, fixed routes and low prices, pure-electric buses have become a key component of urban transit. Yet day-to-day service is hindered by low fleet availability, limited daily kilometres and poor service quality, all of which erode operation efficiency. Taking Wuhu’s public transport network as a case study, this paper builds a performance-assessment framework for electric bus routes. Using stop-level topology, vehicle specifications and spatiotemporal passenger-flow data from eight representative routes, the study applies the Analytic Hierarchy Process (AHP). A three-tier hierarchy—goal, criteria and alternatives—is constructed; index weights and pairwise comparison matrices are then computed to rank overall route effectiveness. The findings accurately pinpoint operational bottlenecks and furnish quantitative guidance for adaptive network
Hu, TingtingLiang, ZijunLi, XiaoyanZhang, XinyiWang, MengruHu, YufengJiang, Kang
Under the background of advancing the integration of urban and rural road passenger transport and the bus-oriented transformation of scheduled passenger transport, the traditional road passenger transport market has been severely impacted. There is an urgent need to promote the healthy development of chartered passenger transport to meet the public’s demand for high-quality travel. Based on the supply-demand balance theory, a prediction model for chartered passenger transport capacity scale was constructed, and the capacity scale of chartered passenger transport in a typical city was predicted as an example. Finally, countermeasures and suggestions for chartered passenger transport capacity allocation were proposed from five aspects: planning formulation, risk warning, mechanism clarification, performance evaluation, and responsibility implementation.
Zhao, HaibinZhao, XiangyuXing, LiWei, LinghongPeng, XiaoLiao, Kai
In the context of the accelerating urbanization process, the problem of urban traffic congestion has become more severe. Rail transit, with its advantages of high efficiency, convenience, and environmental friendliness, has become a key force in alleviating urban traffic pressure. An in - depth exploration of passengers’ willingness to travel by rail transit is of great significance for optimizing urban traffic planning, improving the service quality of rail transit, and promoting the sustainable development of cities. This article starts from two dimensions: objective factors and passengers’ subjective perceptions, and comprehensively uses a variety of research methods to conduct an in - depth study on passengers’ willingness to travel by rail transit. In terms of objective factors, this article analyzes the differences in subjective perceptions among different passenger groups from the perspectives of gender, age, education level, and occupation. In terms of subjective perceptions
Wang, GangHuang, LeiYang, Yihao
With the rapid development of the worldwide highway transportation industry, continuous box girder bridges have many advantages, such as superior spanning capacity, reasonable force-bearing performance, and low cost, which give them significant strengths in bridge design. However, to ensure that the structural alignment of the girder meets the design and specification requirements, it is necessary to study the laws of alignment changes of cantilever structures during the construction process. This is to reasonably control the alignment of the main girder structure during construction and ensure that the alignment of the completed bridge is consistent with the design alignment. This paper takes a continuous rigid frame bridge on a certain expressway as the engineering basis. Its superstructure is a three-span prestressed concrete continuous box girder with a span of (88 + 160 + 88) m, a bridge width of 16.5 m, and a maximum pier height of 130 m. The paper analyzes the influence of each
Liu, XingshunMa, KunZhao, Qiang
Cross-line operation is a key direction for the integrated development of multi-level rail transit systems in urban agglomerations. Optimizing train operation under cross-line conditions is essential for improving the overall efficiency and service quality of rail networks. This paper addresses the joint problem of suburban railway cross-line operation and express–local train coordination. This paper develops a train scheduling optimization framework that jointly selects service patterns and departure schedules, with the objective of reducing overall costs, including passenger travel time and operating expenses. To solve the model efficiently, an extended Adaptive Large Neighborhood Search (ALNS) algorithm is developed. The proposed approach provides a practical framework for timetable planning in complex cross-line rail systems and contributes to enhancing integrated transit operations.
Zhu, JingyiGuo, XinPan, Jianju
Corrosion of prestressed tendons endangers the safety of bridges, but until now, there has been no effective method to solve the problem of detecting corrosion damage in prestressed tendons of concrete beams. To address this, a magnetic flux leakage detection experimental apparatus for corrosion damage in prestressed tendons based on the principle of magnetic flux leakage inspection has been developed. Using this apparatus, magnetic flux leakage tests were conducted on prestressed tendons after electrochemical corrosion, and the results were compared with simulation analysis to conduct a comparative study. In the experiments, the influence of corrosion severity, corrosion width, and the effect of stirrups on the characteristics of the magnetic flux leakage signals were studied. Magnetic signal feature values were extracted, and a quantification neural network model for corrosion damage was established, which is used to quantify the degree of corrosion damage in prestressed tendons. The
Wang, PengGao, MinDong, LeiZhu, Junliang
The effective measurement and verification of dimensional stability indicators for large size and highly stable structures in service environments is the key to the development of high-precision spacecraft technology. Spatial carrier speckle interferometry technology has been widely used for high-precision measurements in recent years due to its advantages of fast speed, high accuracy, and simple operation. However, the existing technical research only focuses on the measurement under normal temperature and pressure environments, and there is little research on the application under complex operating conditions in space. There is currently no relevant research on the impact of system ambient vibration and noise on measurement stability disturbances. In response to the above issues, a high-precision deformation measurement system suitable for complex environments of high and low temperatures in a vacuum was designed based on spatial carrier measurement technology. A system measurement
Sun, ZijieTang, XiaojunChen, DongkangkangYang, DeyuYu, WentaoLi, XiaqiaoXin, Liang
In order to reduce traffic accidents and losses in long downhill sections of expressways, giving drivers reasonable prevention and control means of information induction can improve the safety of long downhill sections. The location of the accompanying information service of the driver's vehicle terminal and the rationality of the intervention information are worth studying. This study takes a high-speed long downhill road as an example, divides the risk level of the long downhill road based on the road safety risk index model, and verifies it with the help of driving behavior data. Secondly, three coverage schemes of sensing devices are designed according to the results of risk classification, and the HMI interface of accompanying information service is designed according to the different coverage degrees of sensing devices. Finally, a driving simulation experiment was carried out based on the driving simulator, and the speed control level, psychological comfort level, operational
Wang, YuejiaWeng, WenzhongLuan, SenDai, Yibo
This paper explores the adaptability and reliability testing methods of electric vehicles under the unique high-temperature and high-humidity climate conditions in Southeast Asia. The focus of the research here is on five key performance evaluation contents, namely reliability driving test, charging performance test, range assessment, air conditioning cooling efficiency, and in-vehicle air quality monitoring. Relying on a meticulously designed experimental plan, standardized testing procedures, and comprehensive data analysis, this paper assesses the performance of electric vehicles under extreme environmental conditions. The research results show that the climate in Southeast Asia poses significant challenges to the battery systems, powertrains, and thermal management systems of electric vehicles. Based on empirical results, some improvement suggestions are made to support the deployment and application of electric vehicles in this region.
Wang, WeijieDeng, TianhaoWu, YilongZang, Haonan
Focusing on the deformation warning criteria for a new four-lane tunnel affected by an existing tunnel, this study employs numerical simulation to analyze the ultimate strain of the equivalent rock mass. The results reveal the ultimate shear strain and ultimate tensile strain of Class V surrounding rock, offering critical insights for deformation control and early warning systems. Relying on the Maaoling Tunnel Project, the tunnel planar analysis model is established based on the finite difference FLAC3D software to analyze the deformation and strain distribution pattern of the surrounding rock of the new tunnel under different distances and reduction factors between the new and the existing tunnel. Finally, the tunnel crown settlement as an indicator, the establishment of the Maaoling Tunnel V surrounding rock conditions of different distances construction safety warning standard for the construction of large-span tunnels and early warning provides the basis for the relevant
Zhang, YufanTian, WeiLiu, DongxingKang, XiaoyueChen, LimingZheng, Xiaoqing
Road maintenance plays a vital role in maintaining road conditions and ensuring safety, especially in a country with an extensive road network like China. To accurately predict pavement performance, optimize maintenance strategy, reduce cost and improve road efficiency, the paper systematically combed and evaluated the prediction model of pavement performance. Firstly, the importance of pavement maintenance and the background of pavement maintenance performance prediction model are described, and explicit models (mechanical-empirical model, stochastic process, time series analysis) and machine learning models (regression analysis, support vector machine, integrated learning, artificial neural network, deep learning) are introduced respectively. The basic principle, representative study, advantages and disadvantages of each model are introduced in detail. Comparative analysis shows that the traditional explicit model is simple and effective, easy to explain, but difficult to deal with
Ma, MuyunDong, QiaoLin, Yelong
In the context of mounting urban transportation demands, coupled with the imperatives for energy conservation and carbon reduction, incumbent tram systems confront a range of challenges. This paper proposes a green and low-carbon technological framework for tram, encompassing three phases of planning, design, construction, and operation management. It elucidates the energy-saving and environmental protection technical measures inherent in each phase, accompanied by a thorough analysis of their respective advantages and ramifications. The paper further puts forward suggestions for the green and low-carbon transformation of trams, providing both theoretical guidance and practical reference for the sustainable development of trams.
Luan, Zhi-GangZhou, Hai-ZhuWang, Yuan-QiaoCai, Jing-BiaoZhou, Li-NingZheng, Liang-JiTian, Jiu-Li
As a part of high-capacity public transportation system, subway stations necessitate evaluations from passengers’ perspective, which is the goal of this study. It took Shenzhen Metro as an object, employing field observations and questionnaire interviews as primary methods. The questionnaire was structured across four dimensions: subjects demographics, travel routines and in-station experiences, evaluations of wayfinding systems and facilities, and suggestions for improvements. Data analysis reveals that the majority of the subjects use the subway for daily commuting, and the congestion spots are concentrated at station entrances/exits, security checkpoints, vertical circulation points, and train door zones. The subjects’ overall satisfaction with Shenzhen Metro is quite high, driven primarily by wayfinding signage efficacy, route fluency (entry/exit/transfer), and safety perceptions. Subway station design should take spatial layouts and passenger flow optimization into consideration
Wu, XiangyangGan, Xuanci
The half-through arch bridge, known for its efficient structural design and seamless integration with the surrounding environment, is widely utilized in urban transportation infrastructure. However, during operation, the hangers of the through and half-through arch bridge are exposed to various factors, including environmental conditions and cyclic traffic loads, which often cause the hanger of these bridges to rust and fracture, will lead to structural damage or even the collapse of the entire bridge. Therefore, investigating the dynamic performance of half-through arch bridges, both before and after hanger damage, under vehicle-bridge coupling is of paramount importance for understanding the overall performance of the bridge. In this study, a half-through arch bridge was selected as the subject of investigation. A three-dimensional finite element model of the bridge was developed based on real-world engineering projects, and a numerical simulation of the vehicle-bridge coupling
Chen, XiaobingJi, Wei
To address the escalating traffic demands and tackle the complex mechanical challenges inherent in in-situ tunnel expansion, this study, grounded in the Huangtuling Tunnel project in Zhejiang Province, China, focuses on the stability evolution of surrounding rock and the mechanical characteristics of structures during the in-situ expansion of existing tunnels under weak surrounding rock conditions. By systematically comparing core post-excavation features—such as surrounding rock displacement fields, ground pressure distribution pat-terns, and mechanical responses of support structures—between newly constructed tunnels and in-situ expanded tunnels, the research reveals key mechanical principles governing the construction of large-section tunnels in weak rock formations. Specifically, the findings are as follows: (1) Both newly constructed and in-situ expanded large-section tunnels exhibit significant spatial heterogeneity in surrounding rock deformation. The vault-spandrel zones serve
Zheng, XiaoqingKang, XiaoyueXu, KaiChen, TaoHuo, XinwangChen, Chuan
At present, the rail transit network in China is well-developed and has become an important means of daily travel for residents. Rail transit stations usually achieve seamless connections with other transportation modes such as buses, taxis, and shared bicycles. It will evolve into an integrated transportation hub, effectively alleviating the pressure on urban surface transportation and playing a pivotal role in dispersing a large number of commuters. Meanwhile, with the vigorous development of rail transit, its energy consumption is increasing. It results in considerable carbon emissions, which poses a huge challenge to China’s goal of achieving carbon neutrality by 2030. In this paper, the building energy consumption simulation tool DesignBuilder is used to model the Tongyuan Road South Station of Suzhou Rail Transit. The energy consumption generated during its operation stage is simulated, and the carbon emissions produced by Tongyuan Road South Station at this stage are calculated
Zhu, Ning
This paper investigates the seismic performance of the prefabricated concrete-filled steel tubular (CFST) bridge pier in the bridge system-level. The proposed prefabricated CFST bridge pier is composed of circular thin-walled CFST double-column, precast I-shaped tie beams, and precast RC cap beam, which are assembled by simply on-stie assembly connections, with advantages in good seismic performance, convenient construction, and comparable material cost. A total of 12 two-span continuous beam bridge cases are designed, including 2 typical bridges with reinforced concrete (RC) piers and 10 bridges with CFST piers. Numerical research on the hysteretic performance of piers in bridge cases, dynamic responses of all bridge cases, and their seismic fragility. The results demonstrate that prefabricated CFST piers outperform RC piers in both load-bearing capacity and energy dissipation, and these piers exhibit reduced transversal displacement at the top and decreased maximum curvature when
Gu, ChaoWang, Xuanding
Rubber components are an important part of the suspension system of high-speed trains, and the complex nonlinear characteristics of rubber parts have a significant impact on the vehicle dynamic performance. This paper establishes a nonlinear dynamics model of the liquid composite swivel arm positioning node, which can reflect the dynamic stiffness and dynamic damping characteristics of the rubber components that change nonlinearly with the frequency and amplitude, and also has a fast calculation speed. The vehicle dynamics simulation model considering the longitudinal stiffness nonlinear characteristics of the arm node is established, and the influence of the stiffness nonlinearity of the liquid composite arm positioning node on the dynamic performance of the vehicle, such as straight-line stability and curve passing ability, is studied in depth through numerical simulation.
Cheng, JunqiangYang, ChenLi, LongtaoCong, RilongHu, Tingzhou
Objective:Methods:Conclusion:
Dai, HongzhouLi, JianZhao, DiLiu, Haoran
The presence of time-varying loads on shell structures can result in the generation of undesirable noise in the time domain. This paper presents a time-domain noise control method based on piezoelectric smart shell structures. Firstly, a coupled time-domain finite element/boundary element method (TDFEM/BEM) is used to calculate the sound pressure radiated from shell structures subjected to arbitrary time-varying loads. Then a classical time-domain CGVF algorithm is used to control the vibration and to suppress the sound radiation from structures. Finally, numerical examples demonstrate a 44.2% reduction in the displacement response, a 35.8% decrease in acceleration response, a 36.2% decline in sound pressure of the central node, and a 28.5% decrease in average surface sound pressure. The results show that after CGVF control, the vibration and radiation noise of the plate/shell structure under time domain load are effectively reduced, which is of great significance in engineering
Zheng, HaoWang, HongfuLi, JingjingZhou, QiangSun, YongZhou, LingZhang, HongliangWang, BaichuanHuang, JunsongLiu, XiaorangYin, Guochuan
Vehicle trajectories encapsulate critical spatial-temporal information essential for traffic state estimation, congestion analysis, and operational parameter optimization. In a Vehicle-to-Infrastructure (V2I) environment, connected automated vehicles (CAVs) not only continuously transmit their own real-time trajectory data but also utilize onboard sensors to perceive and estimate the motion states of surrounding regular vehicles (RVs) within a defined communication range. These multi-source data streams, when integrated with fixed infrastructure-based detectors such as speed cameras at intersections, create a robust foundation for reconstructing full-sample vehicle trajectories, thereby addressing data sparsity issues caused by incomplete CAV penetration. Building upon classical car-following (CF) theory, this study introduces a novel trajectory reconstruction framework that fuses CAV-generated trajectories and infrastructure-based speed detection data. The proposed method specifically
Bai, WeiFu, ChengxinYao, Zhihong
In order to achieve the widespread application of autonomous driving technology in basic freeway segments, especially in the automated decision-making of following and lane changing behaviors, Connected Autonomous Vehicles (CAVs) must be able to reliably complete driving tasks in complex traffic environments. Our study introduces a novel behavior decision-making architecture for connected autonomous vehicles, which employs the Dueling Double Deep Q-Network (D3QN) algorithm as its core methodology. The model optimizes the decision-making ability in complex traffic scenarios by separating action selection and value assessment and implementing them by different neural networks. The multi-dimensional reward function, which comprehensively considers safety, comfort and efficiency, is introduced into the reinforcement learning training of the model. The simulation scenario of the basic freeway segment is established and the model is trained in the mixed traffic flow environment, compared
Hou, ZhiyunYang, Xiaoguang
For shallow-buried tunnels in weak surrounding rock, methods such as the Cross Diaphragm (CRD) method, the Center Diaphragm (CD) method, and the Double-sided Wall Pilot Tunnel method are commonly used for tunnel entry construction. These conventional methods require the installation of numerous temporary supports, which significantly impact the progress of tunnel construction to a certain extent. Based on the Yanfeng Tunnel project, this paper innovatively proposes a combined construction method of “Double-sided Wall + Bench Cut Method.” A simulation model considering three-dimensional terrain information is established to conduct a comprehensive analysis of the construction impact on the entire structure throughout the process. The results indicate that this tunnel entry method can effectively control the displacement of the surrounding rock, ensuring safe tunnel entry while accelerating the construction progress. This provides a reference and guidance for similar projects.
Pan, GendongJia, HongboYang, FengXu, KaiSong, YingZhang, Peng
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Cheng, LizhiGuan, YanyanCheng, XinyuHu, JiangbiFu, YouleiYang, BiyuSong, Shousong