路段交通拥堵风险较大，会在安全、效率、经济、能源和环境几方面造成更严重的后果。

1.行驶安全性降低

在拥堵状态下，车流波动性加剧，经常出现“走走停停”的现象[122]，会增加追尾事故风险。同时，由于长时间处于拥堵状态，出行者易出现烦躁心理，会影响其正常的驾驶行为，在拥堵过程中、拥堵消散后均会导致其他安全问题。

2.路网瘫痪

交通拥堵使得路网密度增大，通行效率降低，且往往呈现一定的蔓延特征。起初，拥堵发生在一个路段或一个交叉路口，形成“点拥堵”。然而，交通流量的快速增长或局部点拥堵未得到及时缓解等导致拥堵在相互关联的路段上蔓延，且主要分布在一条主干道上，形成“线拥堵”。同样地，若拥堵形势愈发严峻且未得到针对性的管控，线拥堵会进一步蔓延，最终广泛分布在路网中，造成区域性大范围拥堵，使得区域路网瘫痪[112]。

3.出行时间与成本增加

交通拥堵使得行驶速度大幅下降，甚至趋向于零，出行者为了完成既定的出行目标需增加额外的时间成本。同时，燃油费也随之增加。

4.能源浪费与环境污染

交通拥堵会对能源与环境产生不良影响。一方面，额外的出行时间会造成燃料等能源的浪费；另一方面，拥堵过程中车辆连续的低速行驶会增加尾气的排放量，对环境影响较大。

参考文献

[1]高坤.从基本图方法到三相交通流理论[D].合肥：中国科学技术大学，2008.

[2]杨泳，户佐安，梁标.城市快速路交通流特性分析[J].西华大学学报(自然科学版)，2016，35(2)：50-55，60.

[3]KERNER B S，REHBORN H.Experimental features and characteristics of traffic jams[J].Physical Review E，Statistical Physics Plasmas Fluids&Related Interdisciplinary Topics，1996，53(2)：R1297-R1300.

[4]KERNER B S，REHBORN H.Experimental properties of complexity in traffic flow[J].Physreve Review E，Statistical Physics Plasmas Fluids&Related Interdisciplinary Topics，1996，53(5)：R4275-R4278.

[5]田钧方.基于基本图和三相交通流理论的离散建模方法研究[D].北京：北京交通大学，2014.

[6]董春娇，邵春福，马壮林，等.阻塞流状态下城市快速路交通流时空特性[J].交通运输工程学报，2012，12(3)：73-79.

[7]冯星宇，周晨静，荣建.基于速度特性的城市快速路常发性交通拥堵研究[J].交通信息与安全，2014(1)：29-33.

[8]何蜀燕，关伟.城市快速路交通流状态跃迁的实证分析[J].中国公路学报，2008，21(5)：81-86.

[9]李林波，吴兵，潘弘，等.城市道路路段拥挤交通流特性研究[J].山东交通学院学报，2010，18(1)：13-16.

[10]马国旗.城市道路交通流特征参数研究[D].北京：北京工业大学，2004.

[11]郝朝静，刘灿齐，原二普.城市次干道自由流车速分析[J].交通科技与经济，2013，15(1)：73-75，87.

[12]庄焰，吕慎.城市道路交通流三参数关系研究[J].深圳大学学报(理工版)，2005，22(4)：373-376.

[13]孙勇.城市干道交通流运动状态特性研究[D].哈尔滨：哈尔滨工业大学，2007.

[14]李继伟.城市主次干路的路段行程时间估计与预测方法研究[D].长春：吉林大学，2012.

[15]杨佩昆，钱林波.交通分配中路段行程时间函数研究[J].同济大学学报(自然科学版)，1994，22(1)：27-32.

[16]BAEK S，KIM B，LIM Y，et al.Impact of rain on travel characteristics on Korean Freeways[R].2009.

[17]WRIGHT C，ROBERG P.The conceptual structure of traffic jams[J].Transport Policy，1998，5(1)：23-35.

[18]MINETA N.National Strategy to Reduce Congestion on America's Transportation Network[R].US Department of Transportation，2006.

[19]DOWNS A.Can traffic congestion be cured? [J].The Washington Post，2006(4)：955-974.

[20]Assocoation A p t.Critical relief for traffic congestion[R].2002.

[21]祝付玲.城市道路交通拥堵评价指标体系研究[D].南京：东南大学，2006.

[22]齐赛，牛犇.城市交叉口存在的主要问题及改善对策[J].中国高新技术企业，2016(1)：97-98.

[23]周勇.城市停车场问题思考[J].城市发展研究，1998(4)：43-44.

[24]EL FAOUZI N-E，BILLOT R，NURMI P，et al.Effects of adverse weather on traffic and safety：State-of-the-art and a European initiative[C]//Proceedings of the 15th International Road Weather Conference，2010.

[25]MAHMASSANI H S，DONG J，KIM J，et al.Incorporating weather impacts in traffic estimation and prediction systems[R].Washington：US Department of Transport，2009.

[26]柳本民.灾害性天气下高速公路运行安全控制技术研究[D].上海：同济大学，2008.

[27]季运文，施其洲，叶玉玲，等.城市轨道交通灾害性天气的定义、分类及研究方向[J].城市轨道交通研究，2005，8(6)：23-27.

[28]中国气象局.公路交通高影响天气预警等级：QX/T 414—2018[S].北京：中国气象出版社，2018.

[29]陈勇.不良气候条件下道路交通安全事故预防系统研究[D].重庆：重庆大学，2007.

[30]GOODWIN L C.Weather impacts on arterial traffic flow[R].Mitretek Systems Inc，2002.

[31]COVA T，CONGER S M.Transportation hazards[M]//KUTZ M.Handbook of Transportation Engineering.New York：McGraw Hill，2004.

[32]ZHANG L，HOLM P，COLYAR J.Identifying and assessing key weather-related parameters and their impacts on traffic operations using simulation[R].FHWA-HRT-04-131.FHWA，U.S.Department of Transportation，2004.

[33]洪建军，张飞军.吉林省冰雪天气道路拥堵现象分析[J].吉林交通科技，2010(2)：19-20.

[34]贾丽霞.恶劣天气下城市主干道交通拥堵的管理对策[J].山西建筑，2011，37(17)：8-9.

[35]和利永.恶劣气候条件下城市主干道交通拥堵问题及其管理对策[D].长沙：中南大学，2009.

[36]杨金顺.适应气候变化的公路网规划理论与方法研究[D].上海：同济大学，2015.

[37]KEAY K，SIMMONDS I.The association of rainfall and other weather variables with road traffic volume in Melbourne，Australia[J].Accident Analysis&Prevention，2005，37(1)：109-124.

[38]YE Z.Evaluation of the Utah DOT weather operations/RWIS program on traffic operations[J].[S.l.]：[s.n.]，2009.

[39]PREVEDOUROS P D，CHANG K.Potential effects of wet conditions on signalized intersection LOS[J].Journal of Transportation Engineering，2005，131(12)：898-903.

[40]AGARWAL M，MAZE T H，SOULEYRETTE R.Impacts of weather on urban freeway traffic flow characteristics and facility capacity[C]//Proceedings of the 2005 Mid-continent Transportation Research Symposium，2005.

[41]CHUNG E，OHTANI O，WARITA H，et al.Does weather affect highway capacity[C]//Proceedings of the 5th International Symposium on Highway Capacity and Quality of Service，Yakoma，Japan，2006.

[42]ALHASSAN H M，BEN-EDIGBE J.Effect of rainfall intensity variability on highway capacity[J].European Journal of Scientific Research，2011，49(1)：18-27.

[43]杨中良，林瑜，高霄.恶劣天气条件下城市快速路通行能力研究[J].交通信息与安全，2010，28(1)：75-78.

[44]肖琳.特殊需求下网络交通拥挤传播机理及态势评估[D].上海：同济大学，2013.

[45]BRILON W，PONZLET M.Variability of speed-flow relationships on German autobahns[J].Transportation Research Record Journal of the Transportation Research Board，1996，1555(1)：91-98.

[46]STERN A D，SHAH V，GOODWIN L，et al.Analysis of weather impacts on traffic flow in metropolitan Washington DC [R]. US Department of Transportation Federal Highway Administration，2003.

[47]WANG Li-xiao，YAMAMOTO T，MIWA T，et al.An analysis of effects of rainfall on travel speed at signalized surface road network based on probe vehicle data[C]//Proceedings of the 5th International Conference on Traffic and Transportation Studies.Xi'an：American Society of Civil Engineers，2006.

[48]TAM M L，LAM W H K，CHEN B，et al.Using automatic vehicle identification data for investigation of rain effects on vehicular travel speeds and travel choice behaviour[C].Proceedings of the 6th International Conference on Traffic and Transportation Studies，2008.

[49]TSAPAKIS I，CHENG T，BOLBOL A.Impact of weather conditions on macroscopic urban travel times[J].Journal of Transport Geography，2013，28：204-211.

[50]曾伟良，龚峻峰，何兆成，等.降雨对城市道路交通行驶速度的影响分析[J].环境科学与技术，2011(S2)：201-205.

[51]PERRIN H，MARTIN P，HANSEN B.Modifying signal timing during inclement weather[J].Transportation Research Record Journal of the Transportation Research Board，2001，1748(1)：66-71.

[52]AGBOLOSU-AMISON S J，SADEK A W，ELDESSOUKI W.Inclement weather and traffic flow at signalized intersections：Case study from Northern New England[J].Transportation Research Record Journal of the Transportation Research Board，2004，1867(1)：163-171.

[53]GILLAM W J，WILHILL R A.UTC and inclement weather conditions[C]//Proceedings of the Road Traffic Monitoring，1992.

[54]SHIN C-H，CHOI K.Saturation flow rate estimation under rainy weather conditions for on-line traffic control purpose[J].KSCE Journal of Civil Engineering，1998，2(3)：211-222.

[55]SADEK A W，AMISON-AGBOLOSU S J.Validating traffic simulation models to inclement weather travel conditions with applications to arterial coordinated signal systems[R].Burlington Vt：University of Vermont，2004.

[56]SISIOPIKU V P，SULLIVAN A，SURHABI S R.Impacts of signal system timings on rain related congestion[J].International Journal of Engineering and Industries，2011，2(1)：1-12.

[57]CHODUR J，OSTROWSKI K，TRACZ M.Impact of saturation flow changes on performance of traffic lanes at signalised intersections[J].Procedia-Social and Behavioral Sciences，2011，16：600-611.

[58]ASAMER J，VAN ZUYLEN H J.Saturation flow under adverse weather conditions[J].Transportation Research Record Journal of the Transportation Research Board，2011，2258：103-109.(www.daowen.com)

[59]刘力力.不利天气条件下城市交叉口交通流特征参数研究[D].北京：北京工业大学，2013.

[60]COOLS M，MOONS E，WETS G.Assessing the impact of weather on traffic intensity[J].Weather，Climate and Society，2010，2(1)：60-68.

[61]DATLA S，SHARMA S.Impact of cold and snow on temporal and spatial variations of highway traffic volumes[J].Journal of Transport Geography，2008，16(5)：358-372.

[62]PEREZ ZURIAGA A M，GARCÍA A，CAMACHO-TORREGROSA F J，et al.Modeling operating speed and deceleration on two-lane rural roads with global positioning system data[J].Transportation Research Record Journal of the Transportation Research Board，2010，2171：11-20.

[63]SHI L，CHENG Y，JIN J，et al.Effects of rainfall and environmental factors on traffic flow characteristics on urban freeway[C].Transportation Research Board Annual Meeting，Washington DC，US，2011.

[64]BELL M G H，IIDA Y.Transportation network analysis[M].John Wiley&Sons，Ltd，1997.

[65]ASAKURA Y，HATO E，KASHIWADANI M.Stochastic network design problem：An optimal link investment model for reliable network[C]//The Network Reliability of Transport：Proceedings of the 1st International Symposium on Transportation Network，Kyoto，Japan，2001.

[66]OGUCHI T.Practical research on queued traffic flow occurrence at capacity bottleneck on expressway basic section[J].Expressways and Automobiles，2001，44(12)：27-34.

[67]BANKS J.Review of empirical research on congested freeway flow[J].Transportation Research Record Journal of the Transportation Research Board，2002，1802(1)：225-232.

[68]KYTE M，KHATIB Z，SHANNON P，et al.Effect of environmental factors on free-flow speed[J].Transportation Research Circular，E-C018：108-119.

[69]ZHAO Y，SADEK A W，FUGLEWICZ D.Modeling the impact of inclement weather on freeway traffic speed at macroscopic and microscopic levels[J].Transportation Research Record Journal of the Transportation Research Board，2012，2272(1)：173-180.

[70]AKIN D，SISIOPIKU V P，SKABARDONIS A.Impacts of weather on traffic flow characteristics of urban freeways in Istanbul[J].Procedia-Social and Behavioral Sciences，2011，16：89-99.

[71]HOOPER E，CHAPMAN L，QUINN A.The impact of precipitation on speed-flow relationships along a UK motorway corridor[J].Theoretical and Applied Climatology，2014，117(1/2)：303-316.

[72]叶佳缘，杨赛霓，刘浩.降雨对高速公路小型车行程时间的影响[J].公路交通科技，2012，29(11)：135-139，158.

[73]施莉娟.不良天气对快速路交通运行影响研究[D].上海：同济大学，2012.

[74]TORREGROSA F，GARCÍA A，BELDA E.Analysis of Impact of Adverse Weather on Freeway Free-Flow Speed in Spain[J].Transportation Research Record，2010：150-159.

[75]IBRAHIM A T，HALL F L.Effect of adverse weather conditions on speed-flow-occupancy relationships[J].Transportation Research Record，1994，1457：184-191.

[76]UNRAU D，ANDREY J.Driver response to rainfall on urban expressways[J].Transportation research record，2006，1980(1)：24-30.

[77]RAKHA H，FARZANEH M，ARAFEH M，et al.Inclement weather impacts on freeway traffic stream behavior[J].Transportation Research Record，2008，2071(1)：8-18.

[78]HOU T，MAHMASSANI H S，ALFELOR R M，et al.Calibration of traffic flow models under adverse weather and application in mesoscopic network simulation[J].Transportation Research Record，2013，2391(1)：92-104.

[79]张存保，万平，梅朝辉，等.雨天环境下高速公路交通流特性及模型研究[J].武汉理工大学学报，2013，35(3)：63-67.

[80]SAJJADI S，SCHROEDER B，ROUPHAIL N.Traffic stream model evaluation under inclement weather conditions using a fused database[C].The 93rd Annual Meeting of Transportation Research Board，Washington DC，USA，2014.

[81]FOOTE R S.Single lane traffic flow control[C]//Proceedings of the 2nd International Symposium on the Theory of Road Traffic Flow，1965：84-103.

[82]POLUS A，POLLATSCHEK M A.Stochastic nature of freeway capacity and its estimation[J].Canadian Journal of Civil Engineering，2002，29(6)：842-852.

[83]PERSAUD B N，HURDLE V F.Some new data that challenge some old ideas about speed-flow relationships[J].Transportation Research Record Journal of the Transportation Research Board，1988，191-198.

[84]HALL F L，GUNTER M A.Further analysis of the flow-concentration relationship[J].Transportation Research Record Journal of the Transportation Research Board，1986，1091：1-9.

[85]GUNTER M A，HALL F L.Transitions in the speed-flow relationship[J].Transportation Research Record，1986，1091：18-21.

[86]WU Ning.A new approach for modeling of Fundamental Diagrams[J].Transportation Research，Part A：Policy and Practice，2002，36(10)：867-884.

[87]OGUCHI T，KATAKURA M，SHIKATA S.Initiation of queued traffic flow at capacity bottlenecks on basic expressway sections[R].2001.

[88]DAGANZO C F.A behavioral theory of multi-lane traffic flow，Part I：Long homogeneous freeway sections[J].Transportation Research Part B：Methodological，2002，36(2)：131-158.

[89]STRICKLAND R I.Traffic operations at vehicle tunnels[C]//Proceedings of the 33rd Annual Meeting of the Highway Research Board，1954.

[90]KOSHI M，KUWAHARA M，AKAHANE H.Capacity of sags and tunnels on Japanese motorways[J].Ite Journal，1992，62(5)：17-22.

[91]NEWMAN L.Traffic operation at two interchanges in California[J].Highway Research Record，1963，27：14-43.

[92]MIKA H S，KREER J B，YUAN L S.Dual mode behavior of freeway traffic[J].Highway Research Record，1969，279：1-13.

[93]ELEFTERIADOU A.A probabilistic model of breakdown at freeway-merge junctions[R].Brooklyn：Department of Civil and Environmental Engineering，Polytechnic University，1994.

[94]GARTNER N H，MESSER C J，RATHI A K.Revised monograph on traffic flow theory[R].Washington DC：Fed Highway Admin，1996.

[95]郝媛，徐天东，孙立军.交通扰动与交通流稳定性机理解析[J].武汉理工大学学报(交通科学与工程版)，2010，34(2)：217-220.

[96]BULLEN A G R.Strategies for practical expressway control[J].Journal of the Transportation Engineering Division，1972，98(3)：599-605.

[97]BANKS J H.Two-capacity phenomenon at freeway bottlenecks：A basis for ramp metering? [J].Transportation Research Board，1991，1320：83-90.

[98]ELEFTERIADOU L，ROESS R P，MCSHANE W R.Probabilistic nature of breakdown at freeway merge junctions[J].Transportation Research Record Journal of the Transportation Research Board，1995，1484：80-89.

[99]LORENZ M，ELEFTERIADOU L.A Probabilistic approach to defining freeway capacity and breakdown[J].Transportation Research Circular，2000，E-C018：84-95.

[100]EVANS J L，ELEFTERIADOU L，GAUTAM N.Probability of breakdown at freeway merges using Markov chains[J].Transportation Research Part B：Methodological，2001，35(3)：237-254.

[101]SUN J，ZHANG J，ZHANG H M.Investigation of early-onset breakdown phenomenon at urban expressway bottlenecks in Shanghai，China[C]//Proceedings of the Transportation Research Board 92nd Annual Meeting，2013.

[102]郝媛，孙立军，徐天东，等.城市快速路交通拥挤分析及拥挤阈值的确定[J].同济大学学报(自然科学版)，2008，36(5)：609-614，630.

[103]TU H，LI H，LINT H V，et al.Modeling travel time reliability of freeways using risk assessment techniques[J].Transportation Research Part A：Policy&Practice，2012，46(10)：1528-1540.

[104]王文成，杨小宝，周映雪，等.基于Cox风险模型的城市道路交通拥堵持续时间分析[J].长安大学学报(自然科学版)，2015(s1)：235-239.

[105]李晨曦.基于交通延误的路网交通状态评价分析[D].北京：北京交通大学，2010.

[106]美国交通研究委员会.道路通行能力手册[M].北京：人民交通出版社，2007.

[107]ASAKURA Y，KASHIWADANI M.Road network reliability caused by daily fluctuation of traffic flow[J]//European Transport，Highways&Planning，1991，19：73-84.

[108]ASAKURA Y.Reliability measures of an origin and destination pair in a deteriorated road network with variable flows[M]//Transportation Networks：Recent Methodological Advances，1999.

[109]DU Z-P，NICHOLSON A.Degradable transportation systems：sensitivity and reliability analysis[J].Transportation Research Part B：Methodological，1997，31(3)：225-237.

[110]BELL M G H，CASSIR C，IIDA Y，et al.A sensitivity-based approach to network reliability assessment[C]//Proceedings 14th International Symposium on Transportation and Traffic Theory，Jerusalem，1999：283-300.

[111]YANG H，LO K K，TANG W H.Travel time versus capacity reliability of a road network[C]//Reliability of Transport Networks.Hertfordshire：RSP Ltd.，2000：119-138.

[112]赵辉.北京市交通拥堵特征及其影响因素分析[D].北京：北京交通大学，2017.

[113]TRB.Highway Capacity Manual[C]//Proceedings of the Special Report 209，Transportation Research Board，National Research Council，2000.

[114]BRILON W，GEISTEFELDT J，REGLER M.Reliability of freeway traffic flow：A stochastic concept of capacity[M]//Reliability of Freeway Traffic Flow.Transportation and Traffic Theory，2005.

[115]冯毅文.基于大规模车辆轨迹数据的道路交叉口排队长度探测[D].深圳：深圳大学，2017.

[116]曹静.城市快速路交通拥堵特征与实时排队长度确定方法研究[D].西安：长安大学，2016.

[117]VITI F，VAN ZUYLEN H J.Probabilistic models for queues at fixed control signals[J].Transportation Research Part B：Methodological，2010，44(1)：120-135.

[118]张和生，张毅，胡东成.路段平均行程时间估计方法[J].交通运输工程学报，2008，8(1)：89-96.

[119]IIDA Y，WAKABAYASHI H.An aproximation method of terminal reliability of a road network using partial minimal path and cut set[C]//Proceedings of the 5th World Conference on Transport Research，Yokohama，Japan，1989.

[120]ASAKURA Y，HATO E，KASHIWADANI M.Stochastic network design problem：An optimal link improvement model for reliable network.[M]//BELL M G H and LIDA Y eds.The Network Reliability of Transport.London：Pergamon Press，2003.

[121]CHEN A，YANG H，LO H K，et al.Capacity reliability of a road network：An assessment methodology and numerical results[J].Transportation Research Part B：Methodological，2002，36(3)：225-252.

[122]伍帅.城市快速路瓶颈路段交通流状态判别及拥堵机理研究[D].广州：华南理工大学，2017.

【注释】

[1]美国双子城是指位于美国明尼苏达州东南部的明尼阿波利斯和圣保罗。