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Causes and statistical characteristics of bridge failures:A review

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Journal of Traffic and transportation Engineering(English Edition) 2022年第3期9卷 388-406页

作者： Guojing Zhang Yongjian Liu Jiang Liu Shiyong Lan Jian Yang School of Highway Chang'an UniversityXian 710064China Research Center of Highway Large Structure Engineering on Safety of Ministry of Education Chang'an UniversityXi'an 710064China AECOM New YorkNY 10158USA

Bridge failure, which is generally associated with serious economic and life losses, is defined as the incapacity of a constructed bridge or its components to perform as specified in the design and construction requirements. This paper presents an overview of current researches on the typical characteristics and causes of bridge failures based on 10 former investigations. Principal causes can be divided into internal causes and external causes or natural factors and human factors. Design error, construction mistakes, hydraulic, collision, and overload are the top 5 leading causes of bridge failures, resulting in more than70% of the bridge failures. Causes of bridge failures are closely related to regional economy,structural type, type of use, material type, and service age. The failure rate is very high for steel bridges, which is inseparable from excessive emphasis on structure strength but lack of consideration on structure stability and fatigue in early years. Researchers need to strengthen their research on the stability and fatigue of steel bridges, as well as inspection and maintenance. Extreme loads such as flood, collision, and overload contribute to a large number of bridge failures because of the lack of extreme loads data and design theory defects. It is critical for such bridges to have sufficient redundancy and capacity protection measures to reduce the probability of bridge failure due to extreme loads. Previous statistical methods and classification methods for the characteristics and causes of bridge failures lack unified standards, and a more scientific method needs to be established. A comprehensive electronic database on bridge damage and failures needs to be developed to establish damage models and conduct forensic studies to improve the design theory and specifications.

关键词： Bridge engineering Bridge failure Statistical characteristic Failure cause Case study

A bibliometric review on stability and reinforcement of special soil subgrade based on CiteSpace

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Journal of Traffic and transportation Engineering(English Edition) 2022年第2期9卷 223-243页

作者： Haiying Wang Wei Zhang Yingzhi Zhang Jian Xu School of Construction Machinery Chang’an UniversityXi'an 710064China shaanxi transportation Holding Group Co. Ltd.Xi'an 710075China School of Management Xi’an University of Science and TechnologyXi'an 710054China

To establish a scientific foundation for further studies and to better understand special soil subgrade research foci and development directions,a visualization analysis of 2601 and 2102 article from 2005 to 2019 was conducted based on the China National Knowledge Infrastructure(CNKI)and Web of Science(WOS)core *** distribution feature,country/region distribution,organization distribution,main source journal distribution,research hotspots and frontier of literature are all analyzed,and the knowledge domain maps are plotted with CiteSpace visualization *** was found that from 2005 to 2019,the analysis uncovered that China,USA,Australia,Iran and India as the top five most productive countries publishing about subgrade stability and reinforcement with special soil,but results from the USA are the most influential ones in this field,the national/regional quantitative analysis showed that the density of international co-occurrence network is higher than that of China,which indicated that the international research on the subgrade stability and reinforcement with special soil is relatively concentrated,and the CNKI research was focused on dynamic compaction methods,adding CFG pile and geogrid to strengthen the soil subgrade and the WOS researches were focused on the use of geosynthetics to strengthen the *** current researches of CNKI were revealed to be the compression and deformation characteristics of lightweight foam soil fill subgrade whereas soft soil subgrade problems and numerical analysis methods were the current research foci in the WOS.

关键词： Road engineering Special soil subgrade Research hotspots CiteSpace Visualization analysis

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DM Code Key Point Detection Algorithm Based on CenterNet

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Computers, Materials & Continua 2023年第11期77卷 1911-1928页

作者： Wei Wang Xinyao Tang Kai Zhou Chunhui Zhao Changfa Liu School of Information Engineering Chang’an UniversityXi’an710018China Algorithm Research and Development department GRGBanking Equipment Co.Ltd.Guangzhou510663China Research and Development department Xi’an Soar Electromechanical TechnologyLtd.Xi’an710043China

Data Matrix(DM)codes have been widely used in industrial *** reading of DM code usually includes positioning and *** positioning is a prerequisite for successful *** image processing methods have poor adaptability to pollution and complex *** deep learning-based methods can automatically extract features,the bounding boxes cannot entirely fit the contour of the *** image processing methods are required for precise positioning,which will reduce *** of the above problems,a CenterNet-based DM code key point detection network is proposed,which can directly obtain the four key points of the DM *** with the existing methods,the degree of fitness is higher,which is conducive to direct *** further improve the positioning accuracy,an enhanced loss function is designed,including DM code key point heatmap loss,standard DM code projection loss,and polygon Intersection-over-Union(IoU)loss,which is beneficial for the network to learn the spatial geometric characteristics of DM *** experiment is carried out on the self-made DM code key point detection dataset,including pollution,complex background,small objects,etc.,which uses the Average Precision(AP)of the common object detection metric as the evaluation *** reaches 95.80%,and Frames Per Second(FPS)gets 88.12 on the test set of the proposed dataset,which can achieve real-time performance in practical applications.

关键词： DM code key point detection CenterNet object detection enhanced loss function

A review of deep learning methods for pixel-level crack detection

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Journal of Traffic and transportation Engineering(English Edition) 2022年第6期9卷 945-968页

作者： Hongxia Li Weixing Wang Mengfei Wang Limin Li Vivian Vimlund School of Information Engineering Chang'an UniversityXi'an 710064China School of Computer Baoji University of Arts and SciencesBaoji 721013China School of Electrical and Electronic Engineering Wenzhou UniversityWenzhou 325035China department of Computer Science and Technology Linkoping UniversityLinköpingSweden

Cracks are a major sign of aging transportation *** detection and repair of cracks is the key to ensuring the overall safety of the transportation *** recent years,due to the remarkable success of deep learning(DL)in the field of crack detection,many researches have been devoted to developing pixel-level crack image segmentation(CIS)models based on DL to improve crack detection accuracy,but as far as we know there is no review of DL-based CIS methods *** address this gap,we present a comprehensive thematic survey of DL-based CIS *** review offers several contributions to the CIS ***,more than 40 papers of journal or top conference most published in the last three years are identified and collected based on the systematic literature review ***,according to the backbone network architecture of the models proposed in them,they are grouped into 10 topics:FCN,U-Net,encoder-decoder model,multi-scale,attention mechanism,transformer,two-stage detection,multi-modal fusion,unsupervised learning and weakly supervised learning,to be ***,our survey focuses on discussing strengths and limitations of the models in each topic so as to reveal the latest research progress in the CIS ***,publicly accessible data sets,evaluation metrics,and loss functions that can be used for pixel-level crack detection are systematically introduced and summarized to facilitate researchers to select suitable components according to their own research ***,we discuss six common problems and existing solutions to them in the field of DL-based CIS,and then suggest eight possible future research directions in this field.

关键词： Crack image segmentation Crack detection Convolutional neural networks Deep learning Systematic literature review

Development of a landscape index to link landscape pattern to runoff and sediment

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Journal of Mountain Science 2022年第10期19卷 2905-2919页

作者： SHI Peng QIN Yan-li LI Peng LI Zhan-bin CUI Ling-zhou State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi'an University of TechnologyXi'an 710048China Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions Xi'an University of TechnologyXi'an 710048China Northwest A&F University Yangling 712100China College of Life and Environmental Science Wenzhou UniversityWenzhou 325035China

Linking landscape indexes to ecological processes is the key topic of landscape ***,traditional landscape metrics based on the Patch-Mosaic Model have no ecological *** this study,the runoff-sediment landscape index coupling land use,topography,soil,and vegetation factors was constructed to link landscape patterns to runoff and *** the study area,the runoffsediment landscape index at the class scale showed an increasing trend from 0.10 in 1995 to 0.26 in *** had a higher runoff-sediment landscape index compared to grassland or *** the landscape scale,the runoff-sediment landscape index showed a decreasing trend since 1995;furthermore,it decreased by 36.24%in 2015 compared with the index in *** runoff-sediment landscape index had higher correlations with runoff and sediment compared with traditional landscape *** analysis showed that the runoffsediment landscape index had a higher contribution to runoff and sediment compared to traditional landscape metrics,explaining 90.1%of the *** soil erosion risk assessed by the runoff-sediment landscape index showed an increasing trend upstream of the Dali River *** attention should be paid to this area in future vegetation restoration attempts,as exploring the impact of landscape pattern changes on ecological processes,especially hydrological processes,plays an important role in comprehensive watershed management.

关键词： Runoff Sediment Landscape index Process-oriented Soil erosion risk Landscape planning

Salt freezing resistance improvement of cement-based materials incorporated with calcined layered double hydroxide

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Journal of Traffic and transportation Engineering(English Edition) 2023年第3期10卷 427-440页

作者： Jinyang Huo Tonghuan Zhang Zhenjun Wang Xiaofeng Wang Xin Ji Pei Wang School of Materials Science and Engineering Chang'an UniversityXi'an 710064China Engineering Research Center of transportation Materials of Ministry of Education Chang'an UniversityXi'an 710064China Henan Communications Planning&Design Institute Co. Ltd.Zhengzhou 450052China

Salt freezing damage has severe impacts on durability of cement-based materials(CBMs).Calcined layered double hydroxide(CLDH),as an efficient environmental-friendly adsorption material,can impart excellent salt freezing resistance to *** this work,salt freezing resistance improvement of CBMs incorporated with CLDH was experimentally evaluated by chloride binding capacity,mass loss rate,relative dynamic elastic modulus,setting time,compressive strength,and micro structure *** these,the salt freezing damage model was established to effectively express the quantitative relationship between influencing factors and evaluation indexes of the salt freezing resistance of *** show that CLDH can reconstruct its original layered structure to form reconstructed layered double hydroxide(RLDH).RLDH combines with chloride ions to form RLDH-Cl recrystallization,which can improve chloride binding capacity and pore structures of CBMs to relieve the salt freezing *** salt freezing damage model indicates that the suitable CLDH content can evidently alleviate the salt freezing damage,which facilitates the quantitative analysis of the effect of CLDH on the salt freezing resistance of CBMs.

关键词： Cement-based materials Calcined layered double hydroxide Salt freezing resistance Micro structure Salt freezing damage

Suppression strategies in different propagation periods of cyberattacks in merging area under connected environment

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Journal of Traffic and transportation Engineering(English Edition) 2023年第6期10卷 1148-1161页

作者： Qiuling Wang Kailiang An Zhizhen Liu Wenying Guan School of transportation Engineering Chang'an UniversityXi'an 710064China School of Traffic and transportation Engineering Changsha University of Science and TechnologyChangsha 410114China

In order to ensure the safety of connected and automated vehicles(CAVs)threatened by cyberattack in the confluence area and mitigate the adverse impact of cyberattack propagation,a framework is built to depict the impact of cyberattacks on traffic *** on this framework,corresponding propagation suppression strategies are proposed for different types of cyberattacks in different *** centralized control,game theory is used to solve the confluence sequence corresponding to the *** results show that the proposed method can effectively inhibit the spread of cyberattacks on the premise of *** initial control effect is the *** with uncontrolled condition,in the 100 timesteps,11 susceptible vehicles are finally added,and the second is the immunity period,in which 10 susceptible vehicles were protected from *** and latency control strategies also protect some *** the control strategy of each stage,the peak value of infected vehicles and the duration of cyberattack are improved compared with the uncontrolled *** addition,the traffic efficiency in the confluence area is also *** method can also be extended to such road types as diverging section,weaving section and intersection,so as to reduce the impact of cyberattacks on road network scale.

关键词： Connected and automated vehicles Cyberattack Propagation dynamics Game theory Vehicle control