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（Founded in 2001 bimonthly ）
Responsible Institution：The Ministry of Education of the People's Republic of China (MOE)
Sponsor：ChangAn University
Publisher：Editorial Department of Journal of Traffic and Transportation Engineering
Chief Editor：Aimin sha
Address： Editorial Department of Journal of Traffic and Transportation Engineering, Chang 'an University, Middle Section of South Second Ring Road, Xi 'an, Shaanxi
Post Code：710064
Phone：029-82334388
Email： jygc@chd.edu.cn
Domestic Distribution：Shaanxi Provincial Newspapers and Periodicals Distribution Bureau of China Post Group Co. Ltd
Foreign Sales：China International Book Trade Group Co. Ltd
Standard Number：
ISSN1671-1637 CN61-1369/U CODEN JYGXAS
ISSN1671-1637 CN61-1369/U CODEN JYGXAS
Collection of Source JournalsMore>
- Ei Compendex（美国《工程索引》
- AJ （俄罗斯《文摘杂志》)
- INSPEC（英国《物理学、电技术、计算机及控制信息社数据库》）
- JST China（《日本科学技术振兴机构中国文献数据库》）
- CSA: Technology（美国《剑桥科学文摘：工程技术》）
- Scopus（荷兰《斯高帕斯数据库》）
- IC（波兰《哥白尼索引》）
- CSCD（《中国科学引文数据库》核心库）
- GCJC（《中文核心期刊要目总览》（第7版））
- CAJCED（《中国学术期刊综合评价数据库》
- CSTPCD（《中国科技论文与引文数据库》）
Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
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Management summary and prospect of transportation and vehicle engineering discipline of NSFC in 2022
Abstract:
To support for building China's strength in transportation and improve the fundamental research of transportation and vehicle engineering, the deepening of the code reform dominated by transportation modes was continued for the discipline of transportation and vehicle engineering on the basis of the discipline construction in 2022. The effort was meant to promote the balanced development of research on different transportation systems. The demand-based and problem-oriented principles should be strengthened, and the tendency to consider only four aspects should not be pursued. Hence, the scientific and technological achievements in theory can be applied in practice. Key scientific challenges and bottlenecks can be identified by organizing seminars and demonstrations based on the solicitation of the book A Hundred Scientific Challenges in Transportation and Vehicle Engineering. In this way, the quality of key and major funded projects can be significantly improved. In this paper, the following detailed information is presented regarding the discipline of transportation and vehicle engineering: the application, acceptance, evaluation, and funding of discipline of transportation and transportation engineering in 2022, the tentative plans and measures of how to conduct the organized research and the roadmap of key and major projects for 2023.
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2023, 23(1): 1-7.
doi: 10.19818/j.cnki.1671-1637.2023.01.001
Abstract:
Six kinds of compatibility evaluation methods of polymer modifiers and petroleum asphalts were summarized including qualitative observation method, rheological method, thermodynamic method, chemical analysis method, topography method, and numerical simulation method. The advantages, disadvantages and applicability of different evaluation methods were analyzed and compared. Furthermore, suitable compatibility evaluation methods were recommended based on the blending reaction characteristics of polymer modifiers and petroleum asphalts, and it also looked forward to the future research direction of compatibility evaluation of polymer modifiers with petroleum asphalts. Research results show that polymer modified asphalt is a viscoelastic material. The phase separation coefficient based on rheological method is more sensitive to detect the difference between petroleum asphalts and polymer modifiers, and is suitable for evaluating their compatibility. A single evaluation index cannot accurately evaluate the compatibility of polymer modifiers and petroleum asphalts, and it is recommended to use multiple analysis methods for comprehensive evaluation. For physically blended polymer modified asphalts, the rheology based phase separation coefficient combined with the topography method can be used to evaluate the compatibility of polymer modified asphalts. For the compatibility evaluation of reactive polymer modifiers and petroleum asphalts, the phase separation coefficient and infrared spectroscopy are recommended. The molecular dynamics simulation method based on thermodynamics can further simulate and explain the interaction mechanism between polymer modifiers and petroleum asphalts from a microscopic perspective by setting appropriate polymer models, interaction temperatures, and other parameters. In the future, the storage time range of cigar tube test can be established according to actual storage conditions of polymer modified asphalts, and on this basis, the appropriate compatibility evaluation methods can be used to dynamically and continuously evaluate the compatibility between polymer modifiers and petroleum asphalts.
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2023, 23(1): 8-26.
doi: 10.19818/j.cnki.1671-1637.2023.01.002
Abstract:
To deepen the understanding of the factors affecting the environmental vibration in metro depots and over-track buildings, the engineering practices and research achievements were systematically reviewed from five aspects, namely, the characteristics of vibration source, control standard, propagation law, prediction method, and vibration mitigation measures, and the existing problems and future research directions were also discussed. Research results show that the currently available evaluation and control standards for the environmental vibration in metro depots and over-track buildings are not uniform. The metro depot needs to be properly divided on the basis of the current standards so that a scientific, uniform, and reasonable standard can be formulated. The vibration of an over-track building is caused by the energy superposition in the load-bearing structures at different distances from the track. The vibration magnitude is determined by the intensity of the vibration source, the coupling loss between the soil and the building structure, and the energy attenuation of the over-track transfer structure. From the perspective of the composite vibration level, a monotonous increase or decrease in vibration with the floor number is not observed. From the perspective of frequency-dependent vibration level, the low-frequency vibration is characterized by global vibration on different floors, while an attenuation trend is demonstrated by the high-frequency vibration above the peak frequency as the floor number rises. The randomness of the vibration source, the uncertainty of the contact between soil and structure, the vibration propagation characteristics of the over-track building structure, and other factors have great influences on the propagation law of vibration within the building. They are also the key factors determining the accuracy of environmental vibration prediction method. Metro depots should be divided according to the characteristics of the vibration sources, and the different periods of engineering design should be segmented. Further studies should be conducted on vibration prediction methods for over-track buildings with a clear vibration transmission path and convenience for efficient applications. The design of vibration mitigation measures for metro depots is mainly focused on the vibration mitigation at the vibration source. The research and application of vibration isolation technologies for propagation paths and sensitive targets are obviously insufficient. Studies need to be conducted on the vibration isolation effect and applicability of permanent vibration isolation measures for propagation paths in near-source fields, to promote the design and application of vibration mitigation measures for building structures, and realize the comprehensive vibration mitigation design for vibration sources, propagation paths, and sensitive targets.
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2023, 23(1): 27-46.
doi: 10.19818/j.cnki.1671-1637.2023.01.003
Abstract:
The perspectives of the type and object of inspection equipment for track maintenance, communication and signaling, and power supply of railway were adopted to review the general development of inspection equipment in different countries. The development histories, technical features, and application situations of comprehensive inspection trains, specialized inspection trains, and on-board inspection devices were discussed. The differences of same type of inspection equipment in China and abroad in design concept, function integration, operation and maintenance were compared, and the shortcomings of Chinese inspection equipment were analyzed. On this basis, the development tendency of the Chinese inspection equipment was distilled by learning advanced experience from other countries and adapting it to Chinese actual situation. Research results show that substantial advances have been achieved by the Chinese inspection techniques for track maintenance, communication and signaling, and power supply of railway. Some fields have reached or approached the world advanced level, nevertheless, actual operation demands still cannot be met by these techniques, mainly manifested in inadequate inspection items, low automation and intelligence level of inspection equipment, insufficient usage of inspection data, and high inspection cost. Due to the above problems, the development of inspection equipment should be oriented towards comprehensive inspection functions, miniaturized and modularized inspection equipment, and intelligent and unmanned inspection process, thereby fostering a modern inspection equipment system featuring high reliability, a full range of inspection items, and accurate inspection data. This system is expected to guide the condition-based maintenance and life cycle management of railway infrastructure.
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2023, 23(1): 47-69.
doi: 10.19818/j.cnki.1671-1637.2023.01.004
Abstract:
To study the fatigue and corrosion fatigue performance of bridge cable steel wires, fatigue and corrosion fatigue experiments of cable steel wires were conducted by using new steel wires of different strength grades, cable steel wires of a cable-stayed bridge in service for seven years, and steel wires treated with artificially accelerated corrosion. According to the macroscopic morphology characteristics of typical fatigue fractures, the fatigue fracture mechanism of cable steel wires was explored. The Weibull distribution function was adopted to fit the stress-fatigue life curves of cable steel wires, and differences in the stress-fatigue life curves of different steel wires were compared. The influences of four key factors including the strength grade, stress ratio, corrosion damage, and corrosion-fatigue damage on the fatigue resistance of cable steel wires were revealed, and the corresponding fatigue strength curves were suggested. Test results show that the uncorroded steel wires have excellent fatigue resistance. With the increase in the strength grade, the fatigue strength of cable steel wires increases significantly, and the corresponding fatigue limit improves gradually. The fatigue strength of cable steel wires decreases significantly as the stress ratio improves. Both the corrosion damage and corrosion-fatigue damage significantly reduce the fatigue strength of cable steel wires, and the remaining fatigue life of cable steel wires is greatly affected by the corrosion-fatigue damage than the single corrosion damage. The fatigue cracks of the new steel wires derive from the surface scratch or uneven places of the material. For the steel wires with corrosion damage and corrosion-fatigue damage, the stress concentration is significantly found at the corrosion pit, the fatigue cracks are originated from the corrosion pit on the steel wire surface, and the probabilities of multi-source crack initiation and irregular crack propagation increase. The influences of strength grade, stress ratio, corrosion damage, and corrosion-fatigue damage of steel wires should be considered comprehensively in the bridge cable fatigue resistance design and safety assessment. The steel wire widely used in bridge cables in China is used in the test, and the fatigue strength obtained can be referenced by the fatigue resistance design and life prediction of bridge cables.
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2023, 23(1): 70-79.
doi: 10.19818/j.cnki.1671-1637.2023.01.005
Abstract:
The mechanism of noise generation at pavement micro-surface was analyzed, five low-noise micro-surfaces were designed and compared with common micro-surfaces, and the texture depths and noises of different micro-surfaces were tested. A three-dimensional texture model of micro-surfaces was constructed based on the digital image processing technology, and the relevant texture parameters were excavated to evaluate the textures and noise characteristics of different micro-surfaces. Two pavement surface texture parameters, namely the probability of convex peak distribution and the proportion of convex peak area, were proposed, and the correlations between the parameters and indoor noise were analyzed. Analysis results show that compared with the micro-surface with common medium gradation, the micro-surface with low-noise gradation can reduce the noise by 3.1 dB approximately. Rubber powder in micro-surface can reduce the surface structure and pendulum value by improving the elasticity and sound absorption characteristics of micro-surface, and the noise can be reduced by 2.0 and 6.3 dB by mixing into the medium gradation and low-noise gradation, respectively. Water-based epoxy resin in micro-surface can reduce the macroscopic texture of pavement by improving the workability during construction, and the noise can be reduced by mixing into the medium gradation. The noise reduction effect is similar to that of micro-surface with low-noise gradation. The average pixel difference calculated based on the three-dimensional texture model has a significant linear relationship with the actual texture depth of micro-surface, with a correlation coefficient of 0.94. The distributions of convex peak heights of micro-surfaces with the medium gradation and low-noise gradation exhibit a linear function and a normal function, respectively, and the adjustment of the gradation can significantly reduce the distribution of the lower convex peak height. Additionally, an increase in the number of low convex peaks can enrich the texture of micro-surface, and thus the probability of convex peak distribution can quantify the texture distribution characteristics of micro-surface. The convex peak height of 0.25 mm is the inflection point of the probability of convex peak height distribution curve, and the percentage of the area with a convex peak height greater than 0.25 mm has a significant linear correlation with the noise on micro-surface compared with the full range of convex peak height, and the correlation coefficient is 0.98.
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2023, 23(1): 80-92.
doi: 10.19818/j.cnki.1671-1637.2023.01.006
Abstract:
To explore the deformation characteristics and mechanisms of cement stabilized macadam aggregate at the culverts, bridges and other transition sections for high-speed railways under different working conditions in coarse-grained sulfate saline soil area, based on the material properties of solidified subgrade filler, the graded gravel with 0-2.5% salt content was used and mixed with different kinds and contents of cements, and the deformation characteristics tests with and without capillary water rising at normal temperature were carried out. Besides, the basic freeze-thaw cycle test of the solidified subgrade bed was performed, and the composition change was analyzed by the XRD test at the same time. Based on the test results, the typical test materials were selected to carry out the subgrade-structure model test subjected to the freeze-thaw cycle. Test results show that without capillary water supply, the deformation of the salt-bearing graded crushed stone sample prepared with ordinary cement can reach 4.2 times that of the sample mixed with 5% special cement. Particularly, with capillary water supply, the deformation of the ordinary cement mixed sample can reach 33.0 times that of the 5% special cement mixed sample. Under different salt contents, the minimum inhibition rate achieved by 3%-5% special cement stabilized graded crushed stone on the deformation reduction of corresponding ordinary cement working condition (caused by capillary water rising) is 60%-80%. Subjected to six basic freeze-thaw cycles, the final deformation of the sample with ordinary cement is 16.0 times that of the sample with high sulfate resistance cement. Under the freeze-thaw cycle condition, the maximum expansion deformation rate of stabilized macadam aggregate mixed with special cement is only 0.2% in subgrade-structure model test. In coarse-grained sulfate saline soil area, although the cement solidified subgrade filler reduces other deformations of subgrade, it is necessary to introduce special cement solidification and other engineering measures for high-speed railway and other projects with strict deformation control requirements because the surrounding salt factors are difficult to avoid and ordinary cement cannot fulfil the requirements of subgrade engineering in saline soil areas.
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2023, 23(1): 93-104.
doi: 10.19818/j.cnki.1671-1637.2023.01.007
Abstract:
To accurately predict the area distributions of water film thickness on the runway under different runway and rainfall conditions, a numerical model of area distribution of water film thickness was built according to the two-dimensional shallow water equations. A numerical algorithm was developed on the basis of the lattice finite volume method and the approximate Riemann solution in Harten, Lax and van Leer (HLL) format. On this basis, the measured data of the water film thickness were incorporated, and the optimal Manning coefficient under the actual rainfall conditions was obtained by the construction of the adjoint equation and the use of the gradient descent method. In this way, results of the two-dimensional shallow water equations were dynamically modified, and the area distribution of water film thickness on the runway was accurately estimated. The influences of the update interval of Manning coefficient and the spatial sampling interval of elevation on the calculation efficiency and accuracy of the model were analyzed by calculation. In the calculation, the measured data of the water film thickness from the security early-warning platform of the Beijing Capital International Airport and the pavement elevation data collected by a vehicle-mounted LiDAR system were employed. The accuracy of the algorithm was verified by the measured data. Research results show that under the real time monitoring requirements of water film thickness and the comprehensive consideration of time consumption and calculation accuracy, the optimal update interval of Manning coefficient is 30-300 s. The optimal spatial sampling interval of elevation is 0.1-0.5 m for the runway with an even surface and 0.10-0.25 m for the runway with diseases such as ruts. Under the actual rainfall conditions, the average error between the calculated water film thickness and the measured value is 0.13 mm, and the maximum error is 0.76 mm. This can meet the monitoring requirement of the airport for the water film thickness. It can be seen that the proposed estimation method for the area distribution of water film thickness on the runway can accurately obtain the distribution and time evolution of water film thickness on a runway with a given elevation. By this method, reliable data support can be provided for the skid resistance evaluation and risk early-warning for wet runways.
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2023, 23(1): 105-114.
doi: 10.19818/j.cnki.1671-1637.2023.01.008
2017, 17(5): 121-137.
摘要：
总结了路面检测重要研究成果, 分析了路面损坏、平整度、车辙、抗滑性能(构造深度) 和结构强度(弯沉) 检测技术的发展现状, 研究了路面检测技术的不足与发展方向。研究结果表明: 国内外路面检测技术的发展经历了3个阶段, 从早期传统的人工检测到20世纪末的半自动化检测, 发展到目前的无损自动检测; 无损自动检测的主要特点是快速与智能化, 采用多源传感器协同工作, 并且集成在多功能道路检测车上, 能够同时检测路面损坏、平整度、车辙、抗滑性能和结构强度以及道路线形与沿线设施等; 在路面损坏检测方面, 采用数字图像检测技术, 实现了路面裂缝的快速检测; 在路面平整度检测方面, 采用激光位移传感技术, 实现了快速自动化检测; 在路面车辙检测方面, 采用激光和数字图像技术, 实现了非接触智能化检测; 在路面抗滑性能和结构强度检测方面, 建立了铺砂法与贝克曼梁法检测结果的相关关系, 实现了基于激光技术的路面构造深度与弯沉快速检测; 为了减少外界因素对现有检测技术和检测设备的干扰, 提高检测信号的信噪比, 应该开发适合各种工况下的路面检测和数据处理方法, 实现路面检测高效化与智能化。
总结了路面检测重要研究成果, 分析了路面损坏、平整度、车辙、抗滑性能(构造深度) 和结构强度(弯沉) 检测技术的发展现状, 研究了路面检测技术的不足与发展方向。研究结果表明: 国内外路面检测技术的发展经历了3个阶段, 从早期传统的人工检测到20世纪末的半自动化检测, 发展到目前的无损自动检测; 无损自动检测的主要特点是快速与智能化, 采用多源传感器协同工作, 并且集成在多功能道路检测车上, 能够同时检测路面损坏、平整度、车辙、抗滑性能和结构强度以及道路线形与沿线设施等; 在路面损坏检测方面, 采用数字图像检测技术, 实现了路面裂缝的快速检测; 在路面平整度检测方面, 采用激光位移传感技术, 实现了快速自动化检测; 在路面车辙检测方面, 采用激光和数字图像技术, 实现了非接触智能化检测; 在路面抗滑性能和结构强度检测方面, 建立了铺砂法与贝克曼梁法检测结果的相关关系, 实现了基于激光技术的路面构造深度与弯沉快速检测; 为了减少外界因素对现有检测技术和检测设备的干扰, 提高检测信号的信噪比, 应该开发适合各种工况下的路面检测和数据处理方法, 实现路面检测高效化与智能化。
2017, 17(3): 151-158.
摘要：
为了提高交通标志识别的正确率和实时性, 提出了一种基于HOG-Gabor特征融合与Softmax分类器的交通标志识别方法。采用Gamma矫正方法提取HOG特征, 采用对比度受限的自适应直方图均衡化方法提取Gabor特征, 基于线性特征融合原理, 将提取的HOG和Gabor特征向量直接串联, 得到刻画交通标志的融合特征向量, 采用Softmax分类器对融合特征向量进行分类, 采用德国交通标志识别基准(GTSRB) 数据库测试了所提方法的有效性, 比较了基于单特征与融合特征的交通标志识别效果。试验结果表明: 在图像增强过程中, 针对HOG特征, 采用Gamma矫正方法的分类正确率最大, 为97.11%, 针对Gabor特征, 采用限制对比度的直方图均衡化方法的分类正确率最大, 为97.54%;采用Softmax分类器的最小分类正确率为97.11%, 耗时小于2s;针对HOG-Gabor融合特征, 采Softmax分类器的识别率高达97.68%, 因此, 基于HOG-Gabor特征融合与Softmax分类器的交通标志识别方法的识别率高, 实时性强。
为了提高交通标志识别的正确率和实时性, 提出了一种基于HOG-Gabor特征融合与Softmax分类器的交通标志识别方法。采用Gamma矫正方法提取HOG特征, 采用对比度受限的自适应直方图均衡化方法提取Gabor特征, 基于线性特征融合原理, 将提取的HOG和Gabor特征向量直接串联, 得到刻画交通标志的融合特征向量, 采用Softmax分类器对融合特征向量进行分类, 采用德国交通标志识别基准(GTSRB) 数据库测试了所提方法的有效性, 比较了基于单特征与融合特征的交通标志识别效果。试验结果表明: 在图像增强过程中, 针对HOG特征, 采用Gamma矫正方法的分类正确率最大, 为97.11%, 针对Gabor特征, 采用限制对比度的直方图均衡化方法的分类正确率最大, 为97.54%;采用Softmax分类器的最小分类正确率为97.11%, 耗时小于2s;针对HOG-Gabor融合特征, 采Softmax分类器的识别率高达97.68%, 因此, 基于HOG-Gabor特征融合与Softmax分类器的交通标志识别方法的识别率高, 实时性强。
2018, 18(1): 13-28.
doi: 10.19818/j.cnki.1671-1637.2018.01.002
摘要：
分析了超高性能混凝土(UHPC)的收缩特性及其随时间发展的一般规律, 总结了材料组成、养护制度与内部温湿度场对UHPC收缩的影响。研究结果表明: UHPC收缩早期(0~7 d)发展快, 占总收缩的61.3%~86.5%, 中期(7~28 d)发展缓慢, 占总收缩的13.5%~27.9%, 后期(28 d后)趋于稳定; UHPC以自收缩为主, 占总收缩的78.6%~90.0%, 是早期开裂的主要诱因; 收缩测试起始时间可取试件成型后1 d(24 h), 终止时间可取90 d或120 d; 在结构设计时, 可参考各国规范取收缩为500~800 με, 热养护后可不考虑残余收缩; 对于收缩预测模型, 各国规范尚未统一, 多借鉴现有的收缩模型, 应完善与修正收缩预测模型; 对于材料组成, 目前集中于纤维、矿物掺合料的种类和掺量对收缩的定量影响, 且各组分对收缩的影响不同, 评价指标较为单一, 应结合结构用途、制备工艺与施工过程等进行综合评价; 对于内部温度与湿度场, 研究对象主要集中于28 d后的普通混凝土与高强高性能混凝土, 应深入研究胶凝材料含量大、组分差异性明显、活性矿物掺合料掺量高的UHPC早期内部温度与湿度场; 为了降低收缩, 基本采用内养护, 添加膨胀剂、减缩剂与粗骨料等措施。可见: 为了减小UHPC收缩的同时又不降低其力学性能, 应该优化UHPC配比, 合理使用外加剂, 采取适当养护制度等措施。
分析了超高性能混凝土(UHPC)的收缩特性及其随时间发展的一般规律, 总结了材料组成、养护制度与内部温湿度场对UHPC收缩的影响。研究结果表明: UHPC收缩早期(0~7 d)发展快, 占总收缩的61.3%~86.5%, 中期(7~28 d)发展缓慢, 占总收缩的13.5%~27.9%, 后期(28 d后)趋于稳定; UHPC以自收缩为主, 占总收缩的78.6%~90.0%, 是早期开裂的主要诱因; 收缩测试起始时间可取试件成型后1 d(24 h), 终止时间可取90 d或120 d; 在结构设计时, 可参考各国规范取收缩为500~800 με, 热养护后可不考虑残余收缩; 对于收缩预测模型, 各国规范尚未统一, 多借鉴现有的收缩模型, 应完善与修正收缩预测模型; 对于材料组成, 目前集中于纤维、矿物掺合料的种类和掺量对收缩的定量影响, 且各组分对收缩的影响不同, 评价指标较为单一, 应结合结构用途、制备工艺与施工过程等进行综合评价; 对于内部温度与湿度场, 研究对象主要集中于28 d后的普通混凝土与高强高性能混凝土, 应深入研究胶凝材料含量大、组分差异性明显、活性矿物掺合料掺量高的UHPC早期内部温度与湿度场; 为了降低收缩, 基本采用内养护, 添加膨胀剂、减缩剂与粗骨料等措施。可见: 为了减小UHPC收缩的同时又不降低其力学性能, 应该优化UHPC配比, 合理使用外加剂, 采取适当养护制度等措施。
2017, 17(3): 121-130.
摘要：
分析了自动驾驶汽车自适应巡航控制(Adaptive Cruise Control, ACC) 和协同自适应巡航控制(Cooperative Adaptive Cruise Control, CACC) 车辆跟驰模型, 从系统控制原理、车车通信技术与车间时距方面阐述了ACC与CACC车辆的异同点; 将目前主流ACC/CACC车辆跟驰模型分为3类: 基于智能驾驶的车辆跟驰模型、加州伯克利大学PATH实验室车辆跟驰模型与基于控制论的车辆跟驰模型, 总结3类车辆跟驰模型的建模思路与主要优缺点; 从道路通行能力、交通安全和交通流稳定性3方面, 分析了ACC/CACC车辆对交通流特性的影响, 及其研究现状与未来发展趋势。研究结果表明: 不同的ACC/CACC车辆跟驰模型对通行能力的影响存在较大差别, ACC/CACC车辆有利于提升交通安全性, 但由于缺乏统一的安全性评价指标, 难以量化ACC/CACC车辆对交通安全性的影响程度; 小规模实车试验验证了ACC车辆具有不稳定的交通流特性, 否定了ACC车辆稳定性数值仿真结果, 而数值仿真试验和小规模实车试验均表明CACC车辆可较好提升交通流稳定性, 因此, 完全依赖于计算机仿真试验无法获得令人信服的结论, 实车试验是ACC/CACC研究的必要途径; 为了完善ACC/CACC在交通领域的研究, 应构建不同ACC/CACC车辆比例下的混合交通流基本图模型、智能网联环境下的ACC/CACC车辆跟驰模型建模方法与ACC/CACC混合交通流稳定性解析方法。
分析了自动驾驶汽车自适应巡航控制(Adaptive Cruise Control, ACC) 和协同自适应巡航控制(Cooperative Adaptive Cruise Control, CACC) 车辆跟驰模型, 从系统控制原理、车车通信技术与车间时距方面阐述了ACC与CACC车辆的异同点; 将目前主流ACC/CACC车辆跟驰模型分为3类: 基于智能驾驶的车辆跟驰模型、加州伯克利大学PATH实验室车辆跟驰模型与基于控制论的车辆跟驰模型, 总结3类车辆跟驰模型的建模思路与主要优缺点; 从道路通行能力、交通安全和交通流稳定性3方面, 分析了ACC/CACC车辆对交通流特性的影响, 及其研究现状与未来发展趋势。研究结果表明: 不同的ACC/CACC车辆跟驰模型对通行能力的影响存在较大差别, ACC/CACC车辆有利于提升交通安全性, 但由于缺乏统一的安全性评价指标, 难以量化ACC/CACC车辆对交通安全性的影响程度; 小规模实车试验验证了ACC车辆具有不稳定的交通流特性, 否定了ACC车辆稳定性数值仿真结果, 而数值仿真试验和小规模实车试验均表明CACC车辆可较好提升交通流稳定性, 因此, 完全依赖于计算机仿真试验无法获得令人信服的结论, 实车试验是ACC/CACC研究的必要途径; 为了完善ACC/CACC在交通领域的研究, 应构建不同ACC/CACC车辆比例下的混合交通流基本图模型、智能网联环境下的ACC/CACC车辆跟驰模型建模方法与ACC/CACC混合交通流稳定性解析方法。
2020, 20(1): 27-41.
doi: 10.19818/j.cnki.1671-1637.2020.01.002
摘要：
为了解近20年世界拱桥的发展情况, 分析了钢拱桥、混凝土拱桥和钢管混凝土拱桥等拱桥的建设和技术创新, 展望了拱桥今后的发展趋势。分析结果表明: 在活载比重较大、动力问题比较突出的高速铁路桥梁中, 拱桥刚度大, 应用优势突出。在跨径方面, 3种大跨径拱桥的平均跨径分别为464、370和425 m, 且最大跨径不断增大, 以钢管混凝土拱桥最为明显。在材料方面, 高强钢在钢拱桥中的应用趋势并不明显; 混凝土拱桥的材料强度随着跨径的增大而不断提高, 超高性能混凝土已经得到应用; 钢管混凝土拱桥的拱肋材料强度在不断提高; 超高性能砂浆的提出将有助于提高圬工拱桥的竞争优势。在结构方面, 主拱采用新材料和钢腹板(杆)-混凝土组合截面, 与其他结构形成组合结构, 以及桥面连续化、轻型化和强调强健性, 是重要的技术进步。在施工技术方面, 钢管混凝土劲性骨架施工法、转体施工法和快速施工法等的发明, 推动着拱桥施工技术的进步。在结构创新与技术进步的推动下, 由于拱桥在美观、经济、结构等方面的独特优势, 今后仍将被大量修建; 超高性能混凝土有望为拱桥发展带来革命性的变化; 在跨径方面, 近期可望取得明显突破的是混凝土拱桥; 桥面系与主拱共同受力、连续化、轻型化和强调强健性也是重要发展方向。
为了解近20年世界拱桥的发展情况, 分析了钢拱桥、混凝土拱桥和钢管混凝土拱桥等拱桥的建设和技术创新, 展望了拱桥今后的发展趋势。分析结果表明: 在活载比重较大、动力问题比较突出的高速铁路桥梁中, 拱桥刚度大, 应用优势突出。在跨径方面, 3种大跨径拱桥的平均跨径分别为464、370和425 m, 且最大跨径不断增大, 以钢管混凝土拱桥最为明显。在材料方面, 高强钢在钢拱桥中的应用趋势并不明显; 混凝土拱桥的材料强度随着跨径的增大而不断提高, 超高性能混凝土已经得到应用; 钢管混凝土拱桥的拱肋材料强度在不断提高; 超高性能砂浆的提出将有助于提高圬工拱桥的竞争优势。在结构方面, 主拱采用新材料和钢腹板(杆)-混凝土组合截面, 与其他结构形成组合结构, 以及桥面连续化、轻型化和强调强健性, 是重要的技术进步。在施工技术方面, 钢管混凝土劲性骨架施工法、转体施工法和快速施工法等的发明, 推动着拱桥施工技术的进步。在结构创新与技术进步的推动下, 由于拱桥在美观、经济、结构等方面的独特优势, 今后仍将被大量修建; 超高性能混凝土有望为拱桥发展带来革命性的变化; 在跨径方面, 近期可望取得明显突破的是混凝土拱桥; 桥面系与主拱共同受力、连续化、轻型化和强调强健性也是重要发展方向。
2018, 18(2): 42-52.
doi: 10.19818/j.cnki.1671-1637.2018.02.005
摘要：
针对轨道交通预制拼装桥墩的受力特点, 提出了采用灌浆套筒和预应力筋连接的拼装方案; 设计了3种不同类型桥墩, 包括整体现浇试件(RC)、预应力钢绞线和灌浆套筒连接的预制拼装试件(PCSS) 与精轧螺纹钢筋和灌浆套筒连接的预制拼装试件(PCTS), 采用拟静力试验方法分析了各种桥墩的各种拟静力指标, 比较了桥墩的抗震性能。试验结果表明: PCSS和PCTS试件的各指标非常接近, 最大误差为2.2%;灌浆套筒会使传统塑性铰区上移至套筒顶部, 说明灌浆套筒对传统塑性铰区域具有局部增强作用, 建议对塑性铰的箍筋加密区高度应额外增加1个套筒高度; 采用预应力筋使试件的混凝土轴压力增大了1倍, 相应的开裂荷载也增大了约1倍; PCSS试件的屈服荷载和极限荷载正负向均值比RC试件分别提高了31%和34%, 等效屈服位移、极限位移和偏移率均值分别比RC试件提高了17%、13%、13%, 但是PCSS试件的延性系数平均降低了10%;在偏移率为6%时, PCSS试件的残余位移均值是RC试件的61%, 显示了较好的自复位能力; 与RC试件相比, PCSS试件的刚度提高了13%。相比于精轧螺纹钢筋, 钢绞线可以适当弯曲与成束, 面积调整灵活, 因此, 采用无黏结预应力筋和灌浆套筒连接的桥墩试件具有良好的使用性能和抗震性能, 可作为预制拼装轨道桥墩的推荐方案。
针对轨道交通预制拼装桥墩的受力特点, 提出了采用灌浆套筒和预应力筋连接的拼装方案; 设计了3种不同类型桥墩, 包括整体现浇试件(RC)、预应力钢绞线和灌浆套筒连接的预制拼装试件(PCSS) 与精轧螺纹钢筋和灌浆套筒连接的预制拼装试件(PCTS), 采用拟静力试验方法分析了各种桥墩的各种拟静力指标, 比较了桥墩的抗震性能。试验结果表明: PCSS和PCTS试件的各指标非常接近, 最大误差为2.2%;灌浆套筒会使传统塑性铰区上移至套筒顶部, 说明灌浆套筒对传统塑性铰区域具有局部增强作用, 建议对塑性铰的箍筋加密区高度应额外增加1个套筒高度; 采用预应力筋使试件的混凝土轴压力增大了1倍, 相应的开裂荷载也增大了约1倍; PCSS试件的屈服荷载和极限荷载正负向均值比RC试件分别提高了31%和34%, 等效屈服位移、极限位移和偏移率均值分别比RC试件提高了17%、13%、13%, 但是PCSS试件的延性系数平均降低了10%;在偏移率为6%时, PCSS试件的残余位移均值是RC试件的61%, 显示了较好的自复位能力; 与RC试件相比, PCSS试件的刚度提高了13%。相比于精轧螺纹钢筋, 钢绞线可以适当弯曲与成束, 面积调整灵活, 因此, 采用无黏结预应力筋和灌浆套筒连接的桥墩试件具有良好的使用性能和抗震性能, 可作为预制拼装轨道桥墩的推荐方案。
2018, 18(6): 131-141.
doi: 10.19818/j.cnki.1671-1637.2018.06.014
摘要：
根据智能汽车技术发展特点和趋势提出了人机共驾的概念; 从切换的发起者、强制性与计划性三方面论述了人机共驾智能汽车控制权切换的分类方法, 分析了广义和狭义2种分类的特点和应用范围; 从驾驶人的认知、驾驶负荷、反应力等方面剖析了人机共驾中人因的特性及其对控制权切换安全性的影响, 总结了控制权切换的试验研究方法和人机交互形式, 指出了控制权切换安全性研究存在的问题和未来发展方向。分析结果表明: 人机共驾智能汽车的应用范围是L2~L3级自动驾驶, 特点是人与系统彼此协同完成动态的驾驶任务; 由系统主动发起、驾驶人被动接管的控制权切换情形与安全性更被业内关注; 驾驶人能有效地对当前驾驶状态进行认知和评估, 进而接管车辆操作, 并最终规避风险, 是保证控制权切换安全性的关键; 人因是影响控制权安全平稳切换的重要因素, 主要表现为认知水平偏低, 切换前后驾驶负荷阶跃式突变, 次任务的影响机理不明确, 反应力随切换场景的不同而差异显著等; 该领域的主要研究还包括接管绩效的评价, 切换时机与人机交互方式的优化以及试验手段的提升等。
根据智能汽车技术发展特点和趋势提出了人机共驾的概念; 从切换的发起者、强制性与计划性三方面论述了人机共驾智能汽车控制权切换的分类方法, 分析了广义和狭义2种分类的特点和应用范围; 从驾驶人的认知、驾驶负荷、反应力等方面剖析了人机共驾中人因的特性及其对控制权切换安全性的影响, 总结了控制权切换的试验研究方法和人机交互形式, 指出了控制权切换安全性研究存在的问题和未来发展方向。分析结果表明: 人机共驾智能汽车的应用范围是L2~L3级自动驾驶, 特点是人与系统彼此协同完成动态的驾驶任务; 由系统主动发起、驾驶人被动接管的控制权切换情形与安全性更被业内关注; 驾驶人能有效地对当前驾驶状态进行认知和评估, 进而接管车辆操作, 并最终规避风险, 是保证控制权切换安全性的关键; 人因是影响控制权安全平稳切换的重要因素, 主要表现为认知水平偏低, 切换前后驾驶负荷阶跃式突变, 次任务的影响机理不明确, 反应力随切换场景的不同而差异显著等; 该领域的主要研究还包括接管绩效的评价, 切换时机与人机交互方式的优化以及试验手段的提升等。
2021, 21(1): 177-198.
doi: 10.19818/j.cnki.1671-1637.2021.01.008
摘要：
从磁悬浮轨道交通的基本原理、磁悬浮列车的技术特点等角度出发，简述了世界各国高速磁悬浮轨道交通的发展概况，对比了常导电磁悬浮、永磁电动磁悬浮、低温超导电动磁悬浮和高温超导磁悬浮等4种磁悬浮方式的研究历史、悬浮特点、悬浮间隙、悬浮能耗、控制系统、技术成熟度与应用情况；采用文献调研、比对、分析、提炼等方法，综述了国内外高校、研究机构和企业对于高速磁悬浮的研究进展；比较了各类磁悬浮轨道交通的原理、技术优势和劣势，分析了高速磁悬浮轨道交通在应用方面的可行性与不足，探讨了4种磁悬浮方式的技术经济性和应用前景与场景；提出了当前发展高速及超高速真空管道磁悬浮轨道交通亟待解决的牵引制动控制、动力和热力学、安全救援、管道密封性能与抽真空效率、无线通信、车内环境控制等6个关键科学问题，并介绍了中国原创高温超导磁悬浮的基础研究及关键技术研发进展与研发计划。研究结果表明：在400~600 km·h-1速度范围可采用常导电磁悬浮或超导磁悬浮技术；在600~1 000 km·h-1速度范围可采用超导磁悬浮技术；1 000 km·h-1及以上的速度可采用高温超导磁悬浮与真空管道或电动磁悬浮与真空管道的磁悬浮技术；作为一种前瞻性研究，高温超导与真空管道磁悬浮关键技术的突破和验证对推动中国乃至世界轨道交通快速发展具有重大而深远的意义。
从磁悬浮轨道交通的基本原理、磁悬浮列车的技术特点等角度出发，简述了世界各国高速磁悬浮轨道交通的发展概况，对比了常导电磁悬浮、永磁电动磁悬浮、低温超导电动磁悬浮和高温超导磁悬浮等4种磁悬浮方式的研究历史、悬浮特点、悬浮间隙、悬浮能耗、控制系统、技术成熟度与应用情况；采用文献调研、比对、分析、提炼等方法，综述了国内外高校、研究机构和企业对于高速磁悬浮的研究进展；比较了各类磁悬浮轨道交通的原理、技术优势和劣势，分析了高速磁悬浮轨道交通在应用方面的可行性与不足，探讨了4种磁悬浮方式的技术经济性和应用前景与场景；提出了当前发展高速及超高速真空管道磁悬浮轨道交通亟待解决的牵引制动控制、动力和热力学、安全救援、管道密封性能与抽真空效率、无线通信、车内环境控制等6个关键科学问题，并介绍了中国原创高温超导磁悬浮的基础研究及关键技术研发进展与研发计划。研究结果表明：在400~600 km·h-1速度范围可采用常导电磁悬浮或超导磁悬浮技术；在600~1 000 km·h-1速度范围可采用超导磁悬浮技术；1 000 km·h-1及以上的速度可采用高温超导磁悬浮与真空管道或电动磁悬浮与真空管道的磁悬浮技术；作为一种前瞻性研究，高温超导与真空管道磁悬浮关键技术的突破和验证对推动中国乃至世界轨道交通快速发展具有重大而深远的意义。
2018, 18(6): 142-158.
doi: 10.19818/j.cnki.1671-1637.2018.06.015
摘要：
针对道路车辆目标检测传统方法需随场景变化提取不同特征, 检测率较低与鲁棒性差的问题, 提出了一种基于Darknet框架下YOLO v2算法的车辆多目标检测方法; 根据目标路段场景与车流量的变化对YOLO-voc网络模型进行改进, 基于ImageNet数据集和微调技术获得分类训练网络模型, 对训练结果和车辆目标特征进行分析后进一步调整改进的算法参数, 最终获得更适合于道路车辆检测的YOLO-vocRV网络模型下车辆多目标检测方法; 为验证检测方法的有效性和完备性, 采用不同车流密度进行了车辆多目标检测试验, 并与经典YOLO-voc、YOLO9000模型进行了对比; 采用改进YOLO-vocRV网络模型, 选取20 000次迭代, 分析了多目标检测结果。试验结果表明: 在阻塞流样本条件下, YOLO9000网络模型检测率为93.71%, YOLO-voc网络模型检测率为94.48%, 改进YOLO-vocRV网络模型检测率达到了96.95%, 因此, 改进网络模型YOLOvocRV检测率较高; YOLO-vocRV模型精确度和召回率均聚集在0.95, 因此, 在获得较好精确度的条件下损失的召回率明显较小, 达到了很好的折中; 采用混合样本训练后, 基于YOLO-vocRV模型的车辆多目标检测方法的检测率在自由流状态下可达99.11%, 同步流状态下可达97.62%, 阻塞流状态下可达到97.14%, 具有较小的误检率和良好的鲁棒性。
针对道路车辆目标检测传统方法需随场景变化提取不同特征, 检测率较低与鲁棒性差的问题, 提出了一种基于Darknet框架下YOLO v2算法的车辆多目标检测方法; 根据目标路段场景与车流量的变化对YOLO-voc网络模型进行改进, 基于ImageNet数据集和微调技术获得分类训练网络模型, 对训练结果和车辆目标特征进行分析后进一步调整改进的算法参数, 最终获得更适合于道路车辆检测的YOLO-vocRV网络模型下车辆多目标检测方法; 为验证检测方法的有效性和完备性, 采用不同车流密度进行了车辆多目标检测试验, 并与经典YOLO-voc、YOLO9000模型进行了对比; 采用改进YOLO-vocRV网络模型, 选取20 000次迭代, 分析了多目标检测结果。试验结果表明: 在阻塞流样本条件下, YOLO9000网络模型检测率为93.71%, YOLO-voc网络模型检测率为94.48%, 改进YOLO-vocRV网络模型检测率达到了96.95%, 因此, 改进网络模型YOLOvocRV检测率较高; YOLO-vocRV模型精确度和召回率均聚集在0.95, 因此, 在获得较好精确度的条件下损失的召回率明显较小, 达到了很好的折中; 采用混合样本训练后, 基于YOLO-vocRV模型的车辆多目标检测方法的检测率在自由流状态下可达99.11%, 同步流状态下可达97.62%, 阻塞流状态下可达到97.14%, 具有较小的误检率和良好的鲁棒性。
2020, 20(3): 168-177.
doi: 10.19818/j.cnki.1671-1637.2020.03.016
摘要：
为了在发生重大突发公共卫生事件时提高城市医疗物资的应急救援效率, 减少人员伤亡与经济损失, 在分析重大突发公共卫生事件特点与应急物流特征的基础上, 将需求紧迫度作为配送影响因素, 提出以辖区人口、感染确诊及疑似病例、医疗物资需求点规模、医护人员数量和医疗物资缺口率为评价指标的医疗物资需求点需求紧迫度评价指标体系; 针对医疗物资应急物流的特点, 调整医疗物资配送时间窗参数, 建立由车辆行驶成本、配送延误惩罚成本和无配送延误补贴费用组成的总配送费用函数, 并考虑配送车辆载重、配送时间窗、医疗物资需求紧迫度等约束条件, 构建使总配送费用最少与需求紧迫度高的需求点优先配送的双重目标, 优化了医疗物资的配送路径; 依托SPSS、Yaahp和MATLAB软件平台, 结合算例, 利用层次分析法与遗传算法求解考虑与不考虑需求紧迫度的医疗物资应急物流配送路径优化模型。研究结果表明: 重大突发公共卫生事件下, 相对于不考虑需求紧迫度的配送路径, 考虑需求紧迫度的最优配送路径不仅对需求紧迫度较高的医疗物资需求点进行优先配送, 同时还使总配送费用减少了5.8%;需求紧迫度的引入能极大地改善调度的盲目性, 基于配送车辆载重、配送时间窗、医疗物资需求紧迫度等约束条件所构建的双目标优化模型能够有效地提高应急救援效率和减少不必要的调度成本。
为了在发生重大突发公共卫生事件时提高城市医疗物资的应急救援效率, 减少人员伤亡与经济损失, 在分析重大突发公共卫生事件特点与应急物流特征的基础上, 将需求紧迫度作为配送影响因素, 提出以辖区人口、感染确诊及疑似病例、医疗物资需求点规模、医护人员数量和医疗物资缺口率为评价指标的医疗物资需求点需求紧迫度评价指标体系; 针对医疗物资应急物流的特点, 调整医疗物资配送时间窗参数, 建立由车辆行驶成本、配送延误惩罚成本和无配送延误补贴费用组成的总配送费用函数, 并考虑配送车辆载重、配送时间窗、医疗物资需求紧迫度等约束条件, 构建使总配送费用最少与需求紧迫度高的需求点优先配送的双重目标, 优化了医疗物资的配送路径; 依托SPSS、Yaahp和MATLAB软件平台, 结合算例, 利用层次分析法与遗传算法求解考虑与不考虑需求紧迫度的医疗物资应急物流配送路径优化模型。研究结果表明: 重大突发公共卫生事件下, 相对于不考虑需求紧迫度的配送路径, 考虑需求紧迫度的最优配送路径不仅对需求紧迫度较高的医疗物资需求点进行优先配送, 同时还使总配送费用减少了5.8%;需求紧迫度的引入能极大地改善调度的盲目性, 基于配送车辆载重、配送时间窗、医疗物资需求紧迫度等约束条件所构建的双目标优化模型能够有效地提高应急救援效率和减少不必要的调度成本。
2013, 13(2): 54-59.
doi: 10.19818/j.cnki.1671-1637.2013.02.008
Abstract:
2014, 14(3): 1-7.
Abstract:
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