Exploring relationships between driving events identified by in-vehicle data recorders,infrastructure characteristics and road crashes

There is an increasing interest in technology-based solutions that can assist drivers in reducing their risk of involvement in road crashes. Previous studies showed that driving events produced by in-vehicle data recorders (IVDR) are applicable for identification of unsafe driving patterns, while combined examinations of driving events and road infrastructure characteristics are rare. This study explored the relationship between the IVDR-driving events, road characteristics and crashes, to examine a potential of the events for predicting crashes and identification of high-risk locations on the road network. The study database included 3500 segments of the interurban roads in Israel, for which the automatically produced IVDR events were matched with road infrastructure characteristics and crashes. Negative-binomial regression models were adjusted for the relationships between road characteristics and driving events, and subsequently, between events and crashes, given the exposure. Significant impacts were found, yet various event types showed different relations to the infrastructure characteristics and different effects on crashes, on various road types. Better road conditions were associated with a decrease in “braking” events and an increase in the “speed alert” events, where road layout constraints and junction proximity were associated with an opposite effect on events. “Braking” and total events showed better potential for predicting crashes on single-carriageway roads, with a positive link to crashes, where for other road types the “speed alert” events were stronger related to crashes, but with a negative link. The heterogeneity of findings indicates a need in further research of the above relationship, with a particular focus on definitions of driving events produced by the IVDR or other technologies.     

Factors affecting mortality of vertebrates on the roads in the Czech Republic

This paper summarizes the results of monitoring animals killed by vehicles on selected roads in the Czech Republic as well as the circumstances of these accidents. Relationships between species of road-killed animals and factors associated with these accidents were evaluated, such as type of road and traffic density, distance from the built-up area, state of vegetation around the road, terrain topology with regard to the road, and the impact of the month/season.     

Commercially managed road funds: managing roads like a business,not like a bureaucracy

Nearly all countries are seriously short of revenues for investment and maintenance of roads. Improving utilization of the existing road budget has helped to narrow, but not eliminate, this financing gap. Requests for additional resources from the government's budget have fallen on deaf ears, because the road sector has grown too large to be fully-financed through general tax revenues. Government tax systems were not designed to finance major economic sectors like roads. Faced with an acute shortage of funds, many road agencies have introduced tolls on high-volume roads and have invited the private sector to build and operate such roads under concession agreements. Although this has narrowed the financing gap, tolling is only economic on a small part of the road network. Tolls have thus had a relatively small impact on the financing gap. Against this background, and mindful of the fact that roads are now 'big business' on the scale of the Fortune Global 500, a growing number of countries have started to 'bring roads into the market place, put them on a fee-for-service basis and manage them like a business.' The fee-for-service concept, though superficially like the user-pay principle and the associated road funds which became popular during the 1950s, differs from user-pay in a number of important respects. The key differences are that: (i) only road user charges go into the road fund (i.e., there are no earmarked taxes); (ii) the fund is managed by a representative board with half or more members representing road users and the business community; (iii) members are nominated by the constituencies they represent and there is an independent chairperson; (iv) financing arrangements are designed to ensure that money is not diverted from other sectors; (v) funds are managed pro-actively by a small secretariat; (vi) there are published financial regulations governing the way funds are managed; (vii) charges are adjusted regularly to meet agreed expenditure targets; and (viii) there are regular technical and financial audits. Other important characteristics are that most commercially managed road funds are managed through a separate road fund administration, funds are channeled to all roads (sometimes even to unclassified roads) and they are introduced as part of a wider agenda to commercialize road management. Some of these road funds have been set up as road public utilities under a board with powers to set their own tariffs.     

Wooded area,forest road-killed animals: Intensity and seasonal differences of road mortality on a small,newly upgraded road in western Romania

The roads are one of the most obvious expressions of modern society, being considered vital for economical growth. Nevertheless, roads have a very strong negative impact upon environment, manifested, among others, by road mortality. In Romania numerous minor roads are currently upgraded and asphalted. In the year 2016, on a road of this kind, in a wooded mountain area, we recorded 1628 road killed animals belonging to 48 taxons. The majority were forest and wet areas animals (earthworms, snails, amphibians, etc), characteristic for the road’s vicinity. Flying or dry areas animals were fewer. The road crosses the forest and the wet areas animals’ habitats. Now, they are certain victims on the road, because its recent upgrade had increased the cars’ speed. Road mortality differed between periods and according to the road surroundings aspect. The highest road mortality intensity was registered at the end of the spring. It has dropped in the summer and then rose again in the autumn, but just moderately. The animals were affected according to their life cycle and ecological demands. On this minor road surrounded by relatively uniform wooded habitats, the road mortality differences were determined in the first place by the demandings and life cycle of the victims, which were affected by meteorological conditions. This studied road is a proof of how forest native animals are exposed once their habitat is crossed by a road.     

庐山西海高速公路文化景观营造技术研究

江西省永修至武宁（庐山西海）高速公路（以下简称庐山西海高速公路）被批准为交通运输部“安全绿色高速公路科技示范工程”,沿线旅游资源丰富。文章从旅游公路的功能和景观特性分析着手,基于文化与公路景观的关系,调研分析了庐山西海高速公路旅游文化景观资源分布情况,提出公路人文景观规划应重点提取当地的人文信息、旅游特色及佛教文化资源加以应用,并对部分设计案例和实施效果进行了介绍。     

Optimal road design through ecologically sensitive areas considering animal migration dynamics

With increasing land transportation requirements in both urban and rural areas, roads are encroaching ever more on animal habitats, where collisions with vehicles are a leading contributor to wildlife mortality. While road designers recognise the importance of accounting for such impacts at the design level, existing approaches simply either ignore viable habitat or avoid such regions entirely. Respectively, this can result in road alignments that are overly damaging to vulnerable species or prohibitively expensive to build and operate. The research presented in this paper investigates the effects of explicitly accounting for animal mortality on the design of a road through an ecologically sensitive area. The model presented achieves this by incorporating a spatially-explicit animal migration and road mortality model into an accepted optimal road alignment algorithm to propose low-cost roads that maintain the animal population above a minimum threshold by the end of a specified design horizon. The new method was applied to an example scenario to demonstrate the effect of setting a minimum required animal population on the road design. This model was able to consistently produce a road that met a minimum required species conservation benefit. This reflected a major improvement over the model that ignored animal habitats while only requiring a minor increase in construction and operating costs compared to the model that avoids habitat.     

膨胀土路基设计、加固与施工技术研究成果推介

膨胀土路基设计、加固与施工技术研究的目的是要解决好长期困扰我国公路建设尤其是西部高速公路建设所面临的膨胀土地质灾害问题。该研究成果对于我国膨胀土路基设计、加固与施工技术及我国相关规范的完善具有重要的实用价值，总体达到国际先进水平，其中膨胀土路堑边坡柔性综合支护技术与改进的CBR测试方法达到国际领先水平。本篇对该技术研究成果进行介绍，以进一步推广使用。     

下坡路段的道路线型设计安全评价方法

长大下坡路段往往是交通事故多发路段,文章基于实测数据,分析长大下坡路段道路线型设计的交通安全影响因素,总结出下坡路段道路加速度模型,根据加速度变化量与交通安全之间的关系,提出以加速度的变化量为评价道路安全的量化指标,确定下坡路段道路线型设计的评价标准.     

Measuring the benefits derived from a transportation investment — a comment

Because an expansion of roads will shift the demand curves for interdependent roads, it may appear difficult to determine the consumer surplus generated by road projects. An extensive literature discusses different measures of consumer surplus, and the conditions under which the different measures give consistent answers. Little attention, however, has been given to a more fundamental problem: under what conditions does consumer surplus measure the benefits of an investment. We discuss both these issues, and explain the close relationship between the conditions guaranteeing the uniqueness of a measure of consumer welfare, and its usefulness in evaluating road projects. No uniqueness problem arises if different roads connect the same origin and destination; consumer surplus can then be measured by use of an aggregate demand curve.     

Clustering of heterogeneous networks with directional flows based on “Snake” similarities

Aggregated network level modeling and control of traffic in urban networks have recently gained a lot of interest due to unpredictability of travel behaviors and high complexity of physical modeling in microscopic level. Recent research has shown the existence of well-defined Macroscopic Fundamental Diagrams (MFDs) relating average flow and density in homogeneous networks. The concept of MFD allows to design real-time traffic control schemes specifically hierarchical perimeter control approaches to alleviate or postpone congestion. Considering the fact that congestion is spatially correlated in adjacent roads and it propagates spatiotemporaly with finite speed, describing the main pockets of congestion in a heterogeneous city with small number of clusters is conceivable. In this paper, we propose a three-step clustering algorithm to partition heterogeneous networks into connected homogeneous regions, which makes the application of perimeter control feasible. The advantages of the proposed method compared to the existing ones are the ability of finding directional congestion within a cluster, robustness with respect to parameters calibration, and its good performance for networks with low connectivity and missing data. Firstly, we start to find a connected homogeneous area around each road of the network in an iterative way (i.e. it forms a sequence of roads). Each sequence of roads, defined as ‘snake’, is built by starting from a single road and iteratively adding one adjacent road based on its similarity to join previously added roads in that sequence. Secondly, based on the obtained sequences from the first step, a similarity measure is defined between each pair of the roads in the network. The similarities are computed in a way that put more weight on neighboring roads and facilitate connectivity of the clusters. Finally, Symmetric Non-negative Matrix Factorization (SNMF) framework is utilized to assign roads to proper clusters with high intra-similarity and low inter-similarity. SNMF partitions the data by providing a lower rank approximation of the similarity matrix. The proposed clustering framework is applied in medium and large-size networks based on micro-simulation and empirical data from probe vehicles. In addition, the extension of the algorithm is proposed to deal with the networks with sparse measurements where information of some links is missing. The results show the effectiveness and robustness of the extended algorithm applied to simulated network under different penetration rates (percentage of links with data).     

树立绿色公路理念 减少对生态环境破坏 —白沙快速出口路绿色公路应用实践

白沙快速出口路从立项至工程开工建设,强调要树立建设绿色公路的理念。为了减少公路建设对沿线生态环境的不利影响。在工程选线阶段,依据《海南省生态保护红线管理规定》中标明的生态红线,尽最大可能避开生态保护Ⅰ类和Ⅱ类红线,对于工艺不能避开的路段采用隧道和桥梁的方式减轻影响程度。在施工期间为了减少新增占地,优化施工组织设计,最大可能实施永临结合,与工可阶段提出的临时占地面积相比,仅为其占地面积的29.6%;采用机制砂、碎石加工等措施,对隧道弃渣进行综合利用,工程所用碎石和砂子,80%以上来自本项目隧道弃渣;将施工便道和地方道路的衔接,减少占地,同时完善地方交通;本着“不破坏就是最大的保护”,尽可能维护沿线既有植被类型,依据群落诱导的植被恢复思想,完善和修复受损植物群落。     

Analysis of the effectiveness of control measures to mitigate road dust emissions in a regional network

The effectiveness of control measures to reduce road dust emissions is analyzed using a year’s data of road dust emissions collected with a mobile sampling platform and a survey of road maintenance practices in the Lake Tahoe Basin of Nevada and California US. Attributes such as sweeping practices, anti-icing, shoulder improvement, pavement condition, trackout, and abrasive material from road segments were analyzed with a feature subset selection algorithm. Street sweeping was found to be an effective means of controlling dust emissions from roads. Road dust from dirty tertiary roads served as a continuous source of suspendable material for adjacent high-speed roads in the winter time. To be most effective, emission control strategies require that not only primary roads, but all roads be swept after snow storms to recover applied abrasive material.     

Highway pricing and capacity choice in a road network under a build–operate–transfer scheme

It is often argued lately that the private sector should be allowed to build and operate roads in a transportation network at its own expense, in return it should receive the revenue from road toll charge within some years, and then these roads will be transferred to the government. This type of build–operate–transfer (B–O–T) projects is currently fashionable worldwide, especially for developing countries short of funds for road construction. One of the important issues concerning a highway B–O–T project is the selection of the capacity and toll charge of the new road and the evaluation of the relevant benefits to the private investor, the road users and the whole society under various market conditions. This paper deals with the selection and evaluation of a highway project under such a B–O–T scheme. For a given road network with elastic demand, mathematical models are proposed to investigate the feasibility of a candidate project and ascertain the optimal capacity and level of toll charge of the new highway. The response of road users to the new B–O–T project is explicitly considered. The characteristic of the problem is illustrated graphically with a numerical example.     

Impacts,management and functional planning criterion of forest road network system in Turkey

In this study are proposed impacts, management and functional planning criterion of forest road network system in rural and urban landscapes of Turkey. Road spacing and road density have been inspected concerning forest roads in production, reforestation, national parks and protection forests of rural and urban landscapes of Turkey. The forest road network was the most expensive human activity in the forests both in terms of economics and environmental effects. Public opinion about the environment has increased in recent years. Sustainable land use planning creates a great challenge for rural and urban road network planning. Further improvements of the network are necessary, to provide for people’s needs in the near future. Harmful effects of road network conflict with the principles of sustainability. When making use of the forest ecosystem for various purposes, care must be taken not to spoil the forest structure. To achieve this, forests must be used according to forestry techniques. So, there is a need for a new planning approach, serving the interests of both accessibility and sustainable environment. In rural landscapes, forest road planning standards (slope, width, pavement, drainage etc.) are different in production, forestation, national parks and protection forests. The need for total forest roads in Turkey was 201,810 km, and that 133,693 km portion of which, corresponding to 66.25%, was constructed by the end of 2005. With a view to be capable of conducting modern forestry activities, our country’s forests should be provided with a systematic road network by completing as soon as possible the construction of the remaining portion of such roads.     

公路养护管理发展探讨

公路的养护管理是延长公路使用寿命,保证交通运行顺畅的重要管理手段。本文主要针对当前公路使用过程中出现的主要病害,结合节能环保的时代主题,针对公路的主要病害分析公路养护过程中主要养护技术的开展,以望为提高公路养护管理水平提供一定的参考价值。     

基于碳中和目标下公路建设的经验观察与分析

本文从低碳环保理念出发,首先提出了基于碳中和目标下的公路工程建设的理念,通过绿色公路的低碳建设对其进行诠释,从公路建设的不同阶段分析了低碳公路建设的要点,并针对目前进行低碳建设所面临的一些难题,提出了几点解决措施,从而大幅度降低公路建设过程中的碳排放,实现碳中和目标下的交通强国建设。     

A census of the US near-roadway population: Public health and environmental justice considerations

This study estimates the size and distribution of the population living near high volume roads in the US, investigates race and income disparities in these near roadway populations, and considers the coverage of the national ambient air quality monitoring network. Every US census block is classified by traffic density and proximity to roads falling within several traffic volume ranges using year 2008 traffic data and the 2010 and 2000 US Census. The results indicate that 19% of the population lives near high volume roads. Nationally, greater traffic volume and density are associated with larger shares of non-white residents and lower median household incomes. Analysis at the county level finds wide variation in the size of near roadway populations and the severity of environmental justice concerns. Every state, however, has some population living near a high volume road and 84% of counties show some level of disparity. The results also suggest that most counties with residents living near high volume roads do not have a co-located regulatory air quality monitor.     

道路环境对交通安全的影响及对策

交通安全,涉及到人、车以及道路和环境等很多因素。近年来,因为各种原因使得有关单位以及人员将更多的将精力放在人、车、道路这几个因素上,对道路交通环境没有过多的考虑和研究。深入研究道路交通环境,有利于道路交通的安全,文章通过对其的研究和分析,得出有关道路交通环境对交通安全的影响和解决措施,对于防止道路交通安全事故具有重要意义。同时为人们的生命财产的安全提供保障、对构建社会主义和谐社会具有很大帮助。     

Private road competition and equilibrium with traffic equilibrium constraints

Toll road competition is one of the important issues under a build-operate-transfer (BOT) scheme, which is being encountered nowadays in many cities. When there are two or more competing firms and each firm operates a competitive toll road, their profits are interrelated due to the competitors' choices and demand inter-dependence in the network. In this paper we develop game-theoretic approaches to the study of the road network, on which multiple toll roads are operated by competitive private firms. The strategic interactions and market equilibria among the private firms are analyzed both in determining their supply (road capacity) and price (toll level) over the network. The toll road competition problems in general traffic equilibrium networks are formulated as an equilibrium program with equilibrium constraints or bi-level variational inequalities. Heuristic solution methods are proposed and their convergences are demonstrated with simple network examples. It is shown that private pricing and competition can be both profitable and welfare-improving.     

Car ownership and public transport use: Revisiting the interaction

At the beginning of the 1980s, it seemed that a consensus was emerging among researchers that public transport service levels, fares or quality had a small but possibly important effect on car ownership, and that this should be taken into account for those purposes where car ownership forecasts are used for developing policy on public transport or roads. Somehow, the findings faded away, and had little effect on policy thinking or on analytical techniques. The results of six surveys carried out in South Yorkshire over the period 1972 to 1991, during which there were extreme changes in public transport policy, tend to support a prima facie case for reopening the question. At the household level, car ownership rates are shown to be more volatile than is often assumed, especially in multiple car households. This volatility provides a context within which the quality of public transport provision appears to influence both the level of car ownership and the relationship between changes in the level of car ownership and changes in public transport use.