Km Of Highway Research Articles

Briefing: Glasgow motorway system – geometric design and outcome

In 1963, the corporation of the city of Glasgow approved plans for 96 km of motorways. To date, 2017, 48 km have been constructed. These are on a grand scale, with 5 km of dual five-lane, 2 km of dual four-lane and over 25 km of dual three-lane motorways. Traffic flows as high as 198 000 vehicles/d have been recorded. Savings of time, accidents and fuel have been realised as a result. The main focus of this briefing paper is the geometric design of the motorways. Scott Wilson Kirkpatrick and Partners, consulting engineers, were responsible for this work. Much emphasis is placed on motorway traffic volumes. This is because road user benefits are directly related to the amount of traffic diverted to the motorways. Also, predicted traffic was a primary factor in the outline design of the motorways.

“Cutting costs to the bone”: the Portuguese experience in renegotiating public private partnerships highways during the financial crisis

How can governments renegotiate public private partnerships (PPPs) in order to reduce public expenditures? In 2011, in the aftermath of the financial and sovereign debt crisis, Portugal asked for financial assistance from the European Union, the European Central Bank, and the International Monetary Fund (“the Troika”). Annual payments to PPPs in the highway sector represented one of the major burdens of public finances. Over the last two decades, Portugal used PPPs to close the “infrastructure gap” by building 4000 km of highways. The Troika demanded that the Portuguese government renegotiate these PPPs in order to reduce annual payments by 30%, and to develop a more sustainable model. This paper describes these renegotiations. We also discuss the strategy of these renegotiation, in order to reduce costs focus on the main motivations for the public and private sector to conduct this process. A reduction of 18% on future payments was achieved, by using five main strategies: (1) reduce operational service levels; (2) transfer operational service to the public sector, at a lower marginal cost; (3) increase the period between “major repairs”; (4) reduce private sector profitability; and (5) change the risk allocation. We detail each strategy and analyse their respective impact on total cost reductions. This paper should be useful to both academics and practitioners, as it describes a complex renegotiation process that led to gains for both sides and reduced public payments in one of countries that used PPPs most aggressively worldwide.

Evaluation of methods for the assessment of attention while driving

The ability to assess the current attentional state of the driver is important for many aspects of driving, not least in the field of partial automation for transfer of control between vehicle and driver. Knowledge about the driver’s attentional state is also necessary for the assessment of the effects of additional tasks on attention. The objective of this paper is to evaluate different methods that can be used to assess attention, first theoretically, and then empirically in a controlled field study and in the laboratory.Six driving instructors participated in all experimental conditions of the study, delivering within-subjects data for all tested methods. Additional participants were recruited for some of the conditions. The test route consisted of 14km of motorway with low to moderate traffic, which was driven three times per participant per condition. The on-road conditions were: baseline, driving with eye tracking and self-paced visual occlusion, and driving while thinking aloud. The laboratory conditions were: Describing how attention should be distributed on a motorway, and thinking aloud while watching a video from the baseline drive.The results show that visual occlusion, especially in combination with eye tracking, was appropriate for assessing spare capacity. The think aloud protocol was appropriate to gain insight about the driver’s actual mental representation of the situation at hand. Expert judgement in the laboratory was not reliable for the assessment of drivers’ attentional distribution in traffic. Across all assessment techniques, it is evident that meaningful assessment of attention in a dynamic traffic situation can only be achieved when the infrastructure layout, surrounding road users, and intended manoeuvres are taken into account. This requires advanced instrumentation of the vehicle, and subsequent data reduction, analysis and interpretation are demanding. In conclusion, driver attention assessment in real traffic is a complex task, but a combination of visual occlusion, eye tracking and thinking aloud is a promising combination of methods to come further on the way.

Change in physiological parameters of calves of various breeds under the transport and pre-slaughter stress

Levakhin VI, Gorlov IF, Azhmuldinov EA, Levakhin YI, Duskaev GK, Zlobina EY, Karpenko EV. 2017. Change in physiological parameters of calves of various breeds under the transport and pre-slaughter stress. Nusantara Bioscience 9: 1-5. The purpose of the research was to study the effect of the animal breed on the stress resistance of young cattle during the motor transportation. Six groups of animals were chosen for the experiment. The first group consisted of calves crossbred from dairy Black and White cows with Hereford bulls, the second – of calves crossbred from dairy cows of Bestuscheff breed with Hereford bulls, the third – of calves purebred of Simmental, the fourth – of calves purebred of Hereford, the fifth – of calves purebred of Aberdeen-Angus, and the sixth – of calves purebred of Limousine breed. The total length of transport was 180 km of highways and local roads. The route consisted of a 5-hour trip without a rest period. The greatest loss in the body weight was determined in the Limousine calves. The calves purebred of Hereford and Simmental breeds are more stress-resistant during the transporting and the pre-slaughter treatment.

Investigating the influence on safety of retrofitting Italian motorways with barriers meeting a new EU standard

ABSTRACTObjective: A new European Union (EU) regulation for safety barriers, which is based on performance, has encouraged road agencies to perform an upgrade of old barriers, with the expectation that there will be safety benefits at the retrofitted sites. The new class of barriers was designed and installed in compliance with the 1998 (European Norm) EN 1317 standards for road restraint systems, which lays down common requirements for the testing and certification of road restraint systems in all countries of the European Committee for Standardization (CEN). Both the older and new barriers are made of steel and are installed in such a way as to avoid vehicle intrusion, but the older ones are thought to be only effective at low speeds and large angles of impact. The new standard seeks to remedy this by providing better protection at higher speeds. This article seeks to quantify the effect on the frequency of fatal and injury crashes of retrofitting motorways with barriers meeting the new standards.Methods: The estimation of the crash modification was carried out by performing an empirical Bayes before–after analysis based on data from the A18 Messina–Catania motorway in Italy. The methodology has the great advantage to account for the regression to the mean effects. Besides, to account for time trend effects and dispersion of crash data, a modified calibration methodology of safety performance was used.Results: This study, based on data collected on 76 km of motorway in the period 2000–2012, derived Crash Modification Factor point estimates that indicate reductions of 72% for run-off-road fatal and injury crashes and 38% in total fatal and injury crashes that could be expected by upgrading an old safety barrier by complying with new EU 1317 standards. The estimated benefit-cost ratio of 5.57 for total crashes indicates that the treatment is cost effective.Conclusions: The magnitude of this benefit indicates that the retrofits are cost-effective even for total crashes and should continue in any European country inasmuch as the estimated Crash Modification Factors are based on treatment sites that are reasonably representative of all European motorways.

Factors affecting raveling of motorway pavements—A field experiment with new additives to the deicing brine

Recently, a novel additive to the de-icing brine has been introduced. It reduces raveling, i.e., the loss of stones of aggregate from asphalt road pavements. To assess the scale of this reduction, a field experiment was conducted. It lasted for two years and consisted of repeated measurements of 540 lane km of motorways in three European countries. Tailored statistical models were used to elucidate the relative importance of different factors influencing raveling—the novel additive, traffic intensity, asphalt age, and initial raveling. The reported results and predictive models are coupled with a detailed accuracy analysis.

Wildlife-vehicle collision hotspots at US highway extents: scale and data source effects

Author(s): Shilling, Fraser M; Waetjen, David P | Abstract: Highways provide commuter traffic and goods movement among regions and cities through wild, protected areas. Wildlife-vehicle collisions (WVC) can occur frequently when wildlife are present, impacting drivers and animals. Because collisions are often avoidable with constructed mitigation and reduced speeds, transportation agencies often want to know where they can act most effectively and what kinds of mitigation are cost-effective. For this study, WVC occurrences were obtained from two sources: 1) highway agencies that monitor carcass retrieval and disposal by agency maintenance staff and 2) opportunistic observations of carcasses by participants in two statewide systems, the California Roadkill Observation System (CROS; http://wildlifecrossing.net/california) and the Maine Audubon Wildlife Road Watch (MAWRW; http://wildlifecrossing.net/maine). Between September, 2009 and December 31, 2014, g33,700 independent observations of g450 vertebrate species had been recorded in these online, form-based informatics systems by g1,300 observers. We asked whether or not WVC observations collected by these extensive, volunteer-science networks could be used to inform transportation-mitigation planning. Cluster analyses of volunteer-observed WVC were performed using spatial autocorrelation tests for parts or all of 34 state highways and interstates. Statistically-significant WVC hotspots were modeled using the Getis- Ord Gi* statistic. High density locations of WVC, that were not necessarily hotspots, were also visualized. Statistically-significant hotspots were identified along ~7,900 km of highways. These hotspots are shown to vary in position from year to year. For highways with frequent deer-vehicle collisions, annual costs fromcollisions ranged from US$0 to gUS$30,000/km. Carcass clusters from volunteer data had very little or no overlap with similar findings from agency-collected WVC data, during a different time-range. We show that both state agency-collected and volunteer-collection of WVC observations could be useful in prioritizing mitigation action at US state-scales by state transportation agencies to protect biodiversity and driver safety. Because of the spatial extent and taxonomic accuracy at which volunteer observations can be collected, these may be the most important source of data for transportation agencies to protect drivers and wildlife.

No evidence of a threshold in traffic volume affecting road-kill mortality at a large spatio-temporal scale

Previous studies have found that the relationship between wildlife road mortality and traffic volume follows a threshold effect on low traffic volume roads. We aimed at evaluating the response of several species to increasing traffic intensity on highways over a large geographic area and temporal period. We used data of four terrestrial vertebrate species with different biological and ecological features known by their high road-kill rates: the barn owl (Tyto alba), hedgehog (Erinaceus europaeus), red fox (Vulpes vulpes) and European rabbit (Oryctolagus cuniculus). Additionally, we checked whether road-kill likelihood varies when traffic patterns depart from the average. We used annual average daily traffic (AADT) and road-kill records observed along 1000km of highways in Portugal over seven consecutive years (2003–2009). We fitted candidate models using Generalized Linear Models with a binomial distribution through a sample unit of 1km segments to describe the effect of traffic on the probability of finding at least one victim in each segment during the study. We also assigned for each road-kill record the traffic of that day and the AADT on that year to test for differences using Paired Student's t-test. Mortality risk declined significantly with traffic volume but varied among species: the probability of finding road-killed red foxes and rabbits occurs up to moderate traffic volumes (<20,000AADT) whereas barn owls and hedgehogs occurred up to higher traffic volumes (40,000AADT). Perception of risk may explain differences in responses towards high traffic highway segments. Road-kill rates did not vary significantly when traffic intensity departed from the average. In summary, we did not find evidence of traffic thresholds for the analysed species and traffic intensities. We suggest mitigation measures to reduce mortality be applied in particular on low traffic roads (<5000AADT) while additional measures to reduce barrier effects should take into account species-specific behavioural traits.

The effect of age, gender and roadway environment on the acceptance and effectiveness of Advanced Driver Assistance Systems

The purpose of this paper was to investigate the effect of age, gender and roadway environment on the acceptance as well as effectiveness of the Advanced Driver Assistance Systems (ADAS). Better understanding on the age and gender differences in technology acceptance and effectiveness toward the ADAS on various roadways could help encourage drivers’ use of new technology for safe driving. In this study, 52 drivers participated in on-road field experiments with or without the ADAS providing a forward collision warning and a lane departure warning. Each participant drove approximately 5.5km of rural road (about 10min), 6.2km of urban road (about 25min) and 9.6km of highway (about 10min). Upon completion of these driving sessions, the ADAS-supported group participants (half of all participants) responded to questionnaire. Field experiment results showed that there were significant age and gender differences in the acceptance and effectiveness of the ADAS and the roadway environment affected the effectiveness of the ADAS. Findings from this study indicated that it is essential to assess age and gender differences in effectiveness and acceptance of new in-vehicle technology for avoiding unexpected negative effects on a certain age and gender segment.

Shear strength properties of Dimitrovgrad flysch, Southeastern Serbia

Flysch deposits are common in Serbia. Approximately 15 % of the 250 km of highways currently under construction will be constructed in flysch. In the most southern part of the E80 project, close to the border crossing with Bulgaria, construction of 3-km long cuts, often over 30 m high, is foreseen by the design. The geology of this part of Serbia is mainly characterized by flysch deposits represented by a sequence of sandstone and siltstone, interchanging in different proportions. After excavation of a majority of the cuts, several slopes suffered from global and structural instabilities. This required re-design of one part of the cuts. For this purpose, a geological strength index (GSI) was estimated and the structural features of rock discontinuities were observed on the faces of the surface excavations. This information and data obtained from laboratory testing enabled the determination of five characteristic rock mass types. For every type, shear strength properties were determined based on three criteria: the Hoek–Brown failure criterion; the Mohr–Coulomb criterion; and an hyperbolic nonlinear envelope. During the process of converting the Hoek–Brown parameters to the parameters of hyperbolic envelope, the Levenberg–Marquardt algorithm (LMA) was utilized to solve for the nonlinear regression problem. Verification of the parameters was performed on several examples. The median angle pressure increases exponentially with the GSI value and ranges between the value characteristic for clays and well-graded gravel. The maximum angle difference is obtained for a GSI value of 30. The average normal effective stress acting on the failed slopes, expressed in the form of the stress level ratio (SLR), is below 0.5. This indicates that the curved part of the shear strength envelope is utilized during the shearing. As such, the linear segment overestimates the shear strength.

Landslide cost modeling for transportation infrastructures: a methodological approach

This paper presents a new methodology for ex post assessment of direct landslide costs for transportation infrastructures. The methodology includes tools to compile, model, and extrapolate landslide losses on different spatial scales over time. A landslide susceptibility model enables regional cost extrapolation by means of a cost figure obtained from local cost compilation for a representative case study area. On a local level, cost survey is closely linked with cost modeling, a toolset for cost estimation based on landslide databases. Cost modeling uses landslide disaster management process models (LDMMs) and cost modules to simulate and monetize cost factors for certain types of landslide damage. The landslide susceptibility model provides a regional exposure index and updates the cost figure to a cost index which describes the costs per kilometer of traffic route at risk of landslides. Both indexes enable the regionalization of local landslide losses. The methodology is applied and tested in a cost assessment for highways in the Lower Saxon Uplands, NW Germany, in the period 1980 to 2010. In this 7,400-km2 large mountain region, 77 km of highway is located in landslide hazard area. Annual average costs of US$52,000 per km of highway at risk of landslides are identified as cost index for a local case study area. The cost extrapolation results in annual average costs for highways in the Lower Saxon Uplands of US$4.02 million. This test application as well as a validation of selected modeling tools verifies the functionality of this methodology.

Highway Access Safety Program Evaluation with Uncertain Parameters

Access management in transportation planning can reduce crashes, increase route capacities, and reduce travel times. The literature suggests a need for performance metrics and a decision-aiding framework to guide access management programs across large corridor networks and diverse time horizons. This paper describes a quantitative framework to support access management programs that focus on safety, applying multicriteria analysis, and cost-benefit analysis with parameter uncertainties. The metrics used to assess relative needs at existing access points include crash exposure, crash intensity, traffic exposure, and costs of typical access management activities. Uncertain parameters that influence the estimates of the potential benefits and costs are identified and treated via a numerical interval analysis. The framework is demonstrated at several geographic scales and locations including 7,000 km of highways of a 110,000-km2 region and its several subregions. The results assist decision makers to prioritize which route segments should be addressed sooner and investigated further by elicitation and collection of additional data, reserving right of way, closing access points, planning new alignments, facilitating developer proffers, etc. This approach that combines multicriteria analysis with cost-benefit analysis is transferable to other topics involving transportation engineering and resource allocation. Language: en

DIVERSE PRODUCTIVE ROADSIDES: ECOLOGICALLY INTEGRATING AGRICULTURE INTO OUR HIGHWAY SYSTEM

The extensive under-used area of roadsides along public highways could readily provide valuable environmental, economic, and cultural benefits for society. Furthermore, local food sources are an increasing priority as energy and environmental costs of long-distance transport increase. This article highlights the central goals and principles for introducing food production in roadsides. Seven types of roadside cultivation are considered: market vegetables, grain, fodder, orchard, biofuel, compost, and livestock. Principles important for incorporating food production into roadsides include: location relative to adjacent land uses; wildlife movement and biodiversity; site topography and hydrology; and arrangement of crops based on roadside pollutant concentrations. Potential problems and their solutions are examined, such as: a swale and remediation system for stormwater and aerial pollutants; a banded vegetation pattern with inedible crops close to the road and edible crops farther from the road; and strategically locating trees to narrow the perceived highway width for enhanced driver safety. Major benefits of roadside production include providing additional farmland for farmers, vegetation design that facilitates wildlife movement and reduces the effects of habitat fragmentation, a cultural symbol of productivity in a highly visible landscape, local food for markets and eateries, carbon sequestration, and multi-use right-of-way biodiversity and landscape management. A case study uses the goals and principles pinpointed to outline a specific design strategy for inserting diverse agriculture along 30km of highway (MA I-495) outside Boston, Massachusetts (USA). Now, widespread designs and pilot projects are needed to initiate the next generation of our roadsides, where public appreciation for local food production, multiple uses of infrastructure, and the landscape's wildlife heritage become the norm.

Modified System of Prestressing for New Precast Girders Developed for Highway Bridges

Traditionally the major part of highway bridges in Slovakia are realised using the precast concrete technology. According to latest plans around 200km of highways are going to be built in Slovakia in the following years. New precast prestressed girders of the I shape from the 24 till to 42m spans have been recently designed using the Eurocodes. Combined pretensioning and post- tensioning have been applied for the girder which consists of three elements. Some of experiences from the girders design procedures will be presented in this paper.

Typical Deficiencies in Traffic Safety and Irregularities of Slovenian Roads

In the past three years the first pilot projects in the fields of RSIA (Road Safety Impact Assessment), RSA (Road Safety Audit) and RSI (Road Safety Inspection) have been carried out in Slovenia. The guidelines for these three areas were thus drafted according to the first findings stemming from conducted pilot projects.This paper deals with the findings from the first Slovenian pilot projects in RSI and presents the typical traffic safety deficiencies and irregularities of Slovenian roads and motorways. Pilot projects covered about 36km of motorways and approximately 24km of other state roads.

Application of Soft Computing for Prediction of Pavement Condition Index

The pavement condition index (PCI) is a widely used numerical index for the evaluation of the structural integrity and operational condition of pavements. Estimation of the PCI is based on the results of a visual inspection in which the type, severity, and quantity of distresses are identified. The purpose of this study is to develop an alternative approach for forecasting the PCI using optimization techniques, including artificial neural networks (ANN) and genetic programming (GP). The proposed soft computing method can reliably estimate the PCI and can be used in a pavement management system (PMS) using simple and accessible spreadsheet softwares. A database composed of the PCI results of more than 1,250 km of highways in Iran was used to develop the models. The results showed that the ANN- and GP-based projected values are in good agreement with the field-measured data. In addition, the ANN-based model was more precise than the GP-based model. For more straightforward applications, a computer program was developed based on the results obtained.

Service Life Analysis and Maintenance Program of Pavement Markings in Thailand

Pavement markings are one of the most important highway assets. Good pavement markings provide good visibility for traffic, whereas poor pavement markings can adversely affect traffic operations on highways. However, a limited amount of research has been conducted on the effects of working conditions on the service life of pavement markings. This paper presents duration models for retroreflectivity of thermoplastic pavement markings in Thailand. This approach allows the service life of pavement markings to follow probability distributions in which model parameters are assumed as a function of relevant independent variables such as traffic volumes. The maximum likelihood estimation technique was used to estimate means and standard errors of the model parameters. Retroreflectivity data of thermoplastic pavement markings were collected from the eastern highway network of Thailand, which consists of more than 5,000 km of highways in various traffic conditions. The analysis results showed that traffic volumes had negative effects on the service life of the pavement markings. This paper proposes a preemptive goal program for approximating required budgets to ensure the maintenance of the percentages of good condition pavement markings over the planning horizon. The first-priority goal is to maintain the percentage of control sections that are in good condition, and the second-priority goal is to minimize total maintenance costs. In the illustrative example, the inconsistency between the Thailand Department of Highways' specifications and field practices caused estimated required annual budgets and the deterioration of pavement markings to greatly fluctuate over the planning period. For more consistency between specification and field practice, the proposed models will be applied in a pavement marking management system.

Overconsolidated clays and flysch for embankments in Slovenia

Abstract In Slovenia 512 km of motorways have been constructed since 1994. Most of them run over hilly terrain, where the bedrock is stiff clay and soft argillaceous sedimentary rock. In order to improve the understanding of stiff clays/soft rock behaviour, series of conventional and advanced tests were performed. The inherent suction of freshly compacted material was up to 2000 kPa whereas after construction, it equilibrated at between 100 and 500 kPa. The decrease in suction resulted in material wetting and softening. Therefore, the Proctor compaction diagrams were complemented with the corresponding Soil Water Characteristic Curve (SWCC). The fundamental issue was that during compaction, inherent suction had to be maintained below a certain level and the fills had to be constructed as soil fills. For quality control, the control of soil suction was found to be important as the relative density control. The conventional monitoring with settlement plates, inclinometers and piezometers was complemented with suction and TDR probes and the seasonal water content changes were measured continuously both during and after construction. Several millions of tons of excavated flysch, shales and stiff overconsolidated clays were used for high embankments using this newly developed approach.

Delivering London 2012: structures, bridges and highways

The £673 million Olympic Park structures, bridges and highways project is one of the largest for the London 2012 Olympic and Paralympic Games. It involved delivering 29 bridges and underpasses, 20 km of highways, 16 km of perimeter security fencing, 11 km of retaining walls and 24 games-time operational support areas. Significant design and construction achievements were realised despite a challenging programme, lengthy procurement process and coordination with multiple stakeholders. Designs were developed to high aesthetic standards incorporating innovative approaches, structural forms and unconventional materials while meeting the challenges of constructability and phasing. Given the presence of multiple contractors, efficient management of site logistics and construction programming was essential for safe and effective delivery.

Contributors

Contributors