Le présent document tente de rencontrer deux objectifs principaux. D’une part, établir une synthèse des connaissances et pratiques à propos des chantiers de nuit en Belgique et à l’étranger et, d’autre part, analyser les avantages et inconvénients du travail de nuit au regard de divers paramètres tels que le trafic (congestion, sécurité) et les travaux (qualité, productivité, conduite des travaux), ainsi que les paramètres sociaux (santé des travailleurs, état des conducteurs), économiques (coût des travaux, coûts indirects aux usagers, etc.) et environnementaux (pollution lumineuse, bruit, etc.).
Sur base des références analysées et de l’information reçue, les principaux éléments décisionnels qui orientent le choix du mode d’exploitation d’un chantier routier, y compris le recours au travail de nuit, sont la minimisation des facteurs de gêne (fluidité du trafic) et le maintien d’un niveau acceptable de sécurité sur le tronçon considéré.
En particulier, du point de vue de la limitation de l’impact sur le trafic, il s’agit de planifier des travaux de sorte à réduire l’ampleur et la durée de la gêne occasionnée (sans oublier de tenir compte de l’éventuel report de trafic, organisé ou pas, sur d’autres routes). Concrètement, il s’agira, sur base du trafic existant et en fonction de la période à laquelle se déroule le chantier, de conserver un nombre suffisant de voies de circulation afin de maintenir un niveau de service acceptable. Pour ce faire, on recourt souvent à une classification des sections du réseau routier selon leur sensibilité aux restrictions temporaires et partielles de la circulation.
Dans ce contexte, le recours au travail de nuit ou en dehors des heures habituelles de travail apparaît comme une option qui s’envisage dès lors que d’autres mesures s’avèrent insuffisantes ou impossibles à mettre en oeuvre: utilisation de la bande d’arrêt d’urgence, réduction temporaire de la largeur des voies, mise en place d’une déviation, exécution des travaux en journée mais en dehors des heures de pointe, le tout selon le type de travaux considéré.
Les critiques à propos des chantiers de nuit et leurs nombreux inconvénients sont fréquentes. Cependant, lorsqu’on examine attentivement l’ensemble des facteurs, la différence entre la construction de jour et de nuit n’est pas significative, ni en termes de coût, ni en termes de productivité, de qualité ou de sécurité. Bien entendu, un bon éclairage et un meilleur contrôle de la circulation sont nécessaires, mais surtout, une bonne planification peut atténuer ou limiter l’impact de tous les facteurs moins avantageux de la construction nocturne.
De nombreuses stratégies visant à atténuer les risques doivent être considérées au moment de la prise de décision de réaliser les travaux de nuit, de sorte que le processus d’analyse des risques doit commencer dès les premières étapes du développement du projet.
In Canada, the total length of the winter road network is estimated at 10,000 km. These are roads that are usable only in the winter. Nature controls the state of a winter road’s foundation – natural ground and ice surfaces – which needs to be trafficable and able to support the vehicles’ weight. These surfaces are particularly sensitive to climate change. A large number of adaptation measures were developed over the years, which can be applied at the planning, construction and maintenance stages, and for traffic management. We have reached a stage where increasing our fundamental knowledge base is required. This can be done through research and development (R&D). Avenues of investigation include a field tool to characterize winter roads in a more systematic fashion, by combining physical information (e.g. road grades, cross-slopes, width, over-land vs over-water ratio) with all operational and logistical data (e.g. opening and closure dates, nature of goods transported) into an interactive database. This could be used for capacity and multimodal planning, as well as to guide priorities on road realignment and incremental replacement (partial or complete) by all-weather road segments. Several outstanding questions regarding the bearing capacity and deformational behavior of floating ice roads could also be addressed. Topics that need to be investigated include: ice cover strength, how long a vehicle can be parked on the ice, how cracking patterns affect ice integrity, and the investigation of known procedures, techniques and technologies to reinforce an ice cover.
In the City of London, the total number of collisions has declined between 2008 and 2011, from nearly 8,400 to less than 7,500. However, the number of injury collisions increased from approximately 1,400 to over 1,500 in the same period. Following a worldwide trend of agencies focusing efforts on reducing the number and severity of motor vehicle collisions, in 2014 the City of London (the City) developed a Road Safety Strategy to reduce fatal and injury collisions. In 2017, the City adopted the Vision Zero principles, based on which no loss of life is acceptable, making London one of the early Canadian adopters of Vision Zero.
One of the key elements of the London Road Safety Strategy (LRSS) during the development of the plan, which occurred between 2012 and 2014, was the coalition building effort, which brought together a multidisciplinary team, including engineering, enforcement, public health, and advocacy groups, among others. This multidisciplinary team expanded the previously active London Middlesex Road Safety Committee into a Steering Committee formed by the City of London, Middlesex County, Ministry of Transportation Ontario, London Police Service, Ontario Provincial Police, Canadian Automobile Association, Young Drivers of Canada, London Block Parent Program, London Health Sciences Centre, Middlesex-London Health Unit.
Manitobans are cycling and walking on provincial highways, and this is not always safe. While active transportation (AT) on highways presents multifaceted safety concerns, it is legal to walk or cycle on all provincial highways in Manitoba. Highway rights-of-way may be the only available public corridors that connect people to where they want to go. Highways are not conventionally designed for AT purposes. Nevertheless, highway operators have a role to play in ensuring the safety of all highway users and enhancing the wellbeing of citizens.
It is with this lens that Manitoba Infrastructure developed the AT Policy and Planning Guide to respond to the following questions:
How can a highway operator cost-effectively account for AT safety?
Under what circumstances should a highway operator consider AT?
What are appropriate AT investments for a highway operator?
The outcome of the policy and planning guide development process was to outline the role of Manitoba Infrastructure in addressing AT on provincial highways, and to guide Manitoba Infrastructure’s decision-making process when considering AT users and AT needs, in relation to the provincial highway network.
The following summarizes the policy:
Local governments and/or trail organizations are primarily responsible for the ownership and maintenance of local AT facilities, which includes design, construction, operation, maintenance, funding, liability, and stewardship. MI maintains on-highway AT-related facilities, in order to protect highway safety and operations.
Public transportation, including AT, is an appropriate use of provincial highway rights-of-way, if facilities are appropriately located.
MI will work with local governments and trail developers to ensure that AT facilities are well planned and designed to protect highway safety and operations.
Where there is significant demand for AT on provincial highways, as interregional and/or interprovincial corridors and connections, MI has a responsibility to:
reasonably improve safety and usability
partner with local governments and/or trail organizations to facilitate development of AT facilities
The resulting planning guide presents a three step approach to considering AT, where Manitoba Infrastructure: 1) reviews if there is AT activity at a location, based on an AT trigger map; 2) prioritizes AT activity, given current and latent demands; and 3) determines the appropriate investment. As a further component of the AT Policy and Planning Guide, Manitoba Infrastructure is publishing maps to inform the public about the AT safety implications of various provincial highways.
In 2017, the Ontario Ministry of Transportation (ministry) successfully completed the replacement of the Highway 3 Grand River Bridge at Cayuga, Ontario. The existing bridge constructed in 1924 was a five span, 188m long, steel through truss bridge. This complex project included a number of “firsts” for the ministry. This was the first project in Ontario that was delivered using the Construction Manager General Contractor (CMGC) contract delivery model. The project also included a number of innovative solutions, such as slide-in bridge construction of a 188m five span structure, through collaboration with the contractor during the design phase.
The CMGC model is still a relatively new contract delivery model for the ministry. The intent of CMGC is to form a collaborative team, between the owner, designer and a contractor, which begins in the design phase and continues throughout construction. During the design phase the contractor provides construction expertise and constructability input into the design with the intent to become the general contractor.
This paper provides an overview of the CMGC delivery model, and discusses the rationale for selecting the CMGC contract delivery model for the bridge replacement project in Cayuga. The paper also describes technical solutions developed and implemented by the collaborative CMGC team during both the design and construction phases of the project. Some of the design challenges of the project included the need to construct the replacement bridge while maintaining two-way traffic on the existing bridge; geotechnical challenges related to fractured voided bedrock; the need to maintain existing utility lines across the bridge during the bridge demolition and bridge slide operations; and the need to minimize impacts to the bed and banks of the river.
Furthermore, adding to the complexity of the project, during construction, work was stopped for a period of 17 months while the new bridge was sitting on temporary supports and the existing bridge had already been demolished. The CMGC approach again played an important role, enabling the ministry to effectively manage this unforeseen delay through the collaborative relationship developed with the ministry, designer and contractor.
Following the successes achieved on this complex project, the ministry has extended the use of the CMGC delivery model to a number of other complex projects.
Dubbed locally as “the Octopus”, the Highway 97A / Main Street intersection forms the entrance to Sicamous, British Columbia, a tourism community with a high percentage of elderly residents, and numerous houseboat rental businesses. The original multi-leg, 45-degree skewed intersection configuration was so confusing and geometrically insufficient that local users avoided the intersection. There were no facilities for cyclists or pedestrians, resulting in significant safety concerns with students from the adjacent school crossing irregularly. The retail businesses immediately adjacent to the intersection suffered as a result.
The BC Ministry of Transportation and Infrastructure (MoTI) had identified a 2-lane roundabout as a preferred option for this location but had previously received adverse comment from the trucking industry (BCTA) regarding roundabouts on numbered routes, primarily due to their perceived inability to accommodate oversized loads.
The design of this roundabout therefore needed to carefully balance the safety and operational needs of all users, including oversize permit vehicles, houseboat trailers, and vulnerable users, and required acceptance from the trucking industry and public.
Extensive stakeholder and community engagement, as well as innovative design elements, produced a solution with custom aprons for specific vehicle use to better separate users; standardization of materials, colour and textures to identify intended use; a roll-over median approach island to allow counterflow operation of permit vehicles with pilot cars; and reduced cross fall on circular roadway to reduce heavy vehicle racking and roll-over potential. The design is phased for a double-lane facility ultimately. However, a single-lane was constructed initially to gain familiarity and acceptance and improve safety. Active transportation needs are accommodated by multi-use pathways, cycle paths and ramps, and tactile mats are provided for the visually impaired, making it safe for all active modes and in particular the local school children. The design also includes raingardens and native, drought-tolerant plantings, as well as unique public art features. An unintended spin-off of the project is that several adjacent properties have already been rejuvenated due to the significantly improved access.
This $7.3M project opened in November 2016 and is safely used by heavy and OS/OW permit vehicles. It has been well received by the local council, Splatsin First Nation, BCTA and MoTI. So much so that this project was awarded the 2017 BC MoTI Deputy Minister’s Award of Excellence for Design.
A research project with the goal of identifying universal accessibility parameters for shared streets was developed by the Transportation Branch of the City of Montreal’s Infrastructure, Roads and Transportation Services Department. This project was initiated in the fall of 2016 and completed in the spring of 2017.
The adoption of the Pedestrian Charter in 2006 was a decisive moment for the City of Montreal, as the Charter recognized the pedestrians’ primacy in the urban environment. By designating the pedestrian as the core priority, the City of Montreal wanted to position walking as a primary means of movement, in addition to offering Montrealers a safe and convenient pedestrian environment that would lead to the re-appropriation of the public realm by local residents. The Montreal Transportation Plan, approved in 2008, supports this vision and specifies the need to share the road between all user categories. Measures 14 and 15 of the Transportation Plan respectively focus on redefining the place of motorized transportation and on consolidating the pedestrian environment at the neighbourhood level. In keeping with the Plan’s policy direction, the City of Montreal is developing highly innovative pedestrian infrastructures, including several pilot projects relating to the shared streets concept. The ultimate goal is to develop sustainable mobility at the neighbourhood level by improving pedestrian safety and comfort, encouraging all Montrealers to walk to nearby destinations as a first choice.
An economic and cultural hub in Saskatchewan, Saskatoon has become one of the most attractive places in Canada to live. In the next 25 to 40 years, Saskatoon’s population is expected to double, from 250,000 to 500,000. Based on comprehensive visioning (Saskatoon Speaks), analysis, and planning (Strategic Plan 2013-2023 and Growth Plan to Half a Million), the City recognizes that accommodating growth using a business-as-usual approach would be problematic if not unsustainable.
In order to enhance the quality of life and increase economic activity in Saskatoon, the Growth Plan identifies three interrelated strategies: corridor growth, transit and core bridges. Under the transit strategy, bus rapid transit (BRT) forms the backbone of a multi-modal transportation system supporting the movement of people along major corridors, to key destinations and development nodes.
Work related to the planning and design of the BRT is underway. The BRT concept, configuration, and preliminary design offers solutions that meets the needs of the Saskatoon transit market, Growth Plan objectives, scale of the community, and available funding. The implementation of the BRT will improve transit frequency, reliability, and customer experience, serving existing customers better and attracting new riders. BRT is also a catalyst for city building. BRT is the mobility backbone of several land use intensification initiatives including: Corridor Plans for 22nd Street, College Drive, 8th Street, Preston Avenue and three mixed use Transit Villages at established commercial nodes adjacent to the future BRT lines.
SNC Lavalin O&M is the company responsible for the operations, maintenance and rehabilitation of 275 kilometres of Trans-Canada Highway in New Brunswick; from the Quebec border to Longs Creek (west of Fredericton), and Route 95 between the United States border and Woodstock, until 2033.
During its winter operations, SNC Lavalin O&M utilizes echelon plowing, the practice of staggering snowplows across all lanes of a multi-lane highway. By passing the ridge of snow from the lead snow plow to the following plow, echelon plowing makes it possible to clear accumulation from all lanes at once. It is, however, extremely dangerous for motorists to pass between or around the snowplows while in this formation, due to the possibility of whiteout conditions between the plow trucks. There is also the danger of impact with the back of the right side wing plow as it becomes obscured by snow.
The number of collisions between motorists and the snow plow right wings was an issue even after many public awareness campaigns on the risks involved when passing between the plow trucks.
After the last collision with injury to the plow operator in March 2013, and in the continuing effort to keep motorists as well as employees safe, SNC Lavalin O&M developed a “Safety Swing Arm”. The Safety Swing Arm consists of a 2.7 meter mechanical arm with high intensity flashing lights, installed on the back of the lead plow truck. When the right side wing plow is deployed, the arm simultaneously extends to create a further visual and break-a-way physical barrier between the motorists and the right wing plow. The Safety Swing Arm has been proven to prevent motorists from hitting the right wing while passing the plow during poor visibility conditions.
This paper synthesizes the results of a project completed for the City of Edmonton in 2017 to recommend lane width values for the City’s Complete Streets Design and Construction Standards. The project included a literature review to synthesize research on the safety and speed implications of narrowed lane widths in urban areas; a jurisdictional review to document peer practice for lane widths and all-season operation in winter cities; and an in-service evaluation of the safety implications of the City’s existing lane widths. A cross-sectional population-segmented study was conducted on the effect of lane widths on safety on 626 Edmonton road segments using five years of data. Regression models were developed to understand the effect of lane width on the proportion of speeding vehicles, the frequency of all severity segment collisions, and the frequency of fatal/injury segment collisions. The main conclusion was that speed should be a primary factor in setting context-sensitive design guidelines for lane widths. The paper concludes with the lane width values incorporated into the City’s Complete Streets Design and Construction Standards. Opportunities for future research are discussed.
This paper is based on research carried out for the recent Canadian Transportation Act Review. It examines the potential for short sea shipping in the Great Lakes / St. Lawrence region and considers international best practices and their relevance to Canada. We revisit a study undertaken by MariNova in 2005, which examined the potential for a short sea service between Halifax augmented by a brief analysis of a Montreal-Hamilton service. The analysis removes all of the constraints previously identified and re-considers its viability. The study also examines the potential role for government, in terms of promoting investment in short sea shipping.
For the purposes of this paper we consider short sea shipping to include container, roll-on, roll-off (ro-ro), bulk as well as tug-and barge operations, providing interregional, intraregional and transhipment services. Our definition does not include passenger ferries, although a significant amount of commercial cargo is carried on most of Canada’s ferry services, particularly in the Newfoundland trade.
The Canadian Marine Pilots’ Association (CMPA) recommended in their submissions to the Canadian Transportation Act Review Panel (2014), and more recently to the Minister of Transport (2016) to consider the structure and administration of a new pilotage service when assessing its potential role in the Arctic. As such, the purpose of this paper is to explore pilotage for Canadian arctic waters in the context of the Northern Marine Transportation Corridors (NMTC) Initiative as a means of improving the safety of navigation and the protection of the marine environment. To aid the analysis, the CMPA’s principles of organizing pilotage in Canada will be relied upon: to protect the public interest (i.e., safety); rigorous standards for qualifying as a pilot; recognition of regional differences in operating conditions, navigational challenges, types of marine traffic and supporting infrastructure; and the responsiveness of pilotage to changes in technology, vessels, infrastructure, and traffic patterns. The paper will begin with a brief overview of the necessity of the service, followed by a discussion of how pilotage could be offered in the Canadian Arctic, including how the service relates to the NMTC Initiative, how it could be administered, and what qualifications would be required of an Arctic pilot.
Transportation is one of the major contributors of Greenhouse Gas (GHG) emissions all over the world. In Canada, transportation was the second largest source of GHG emissions in 2014, accounting for 23% of the total emissions nationwide (Environment Canada, 2016). At the provincial level, 38.4% of British Columbia’s GHG emissions came from the transportation sector (BC Ministry of Environment, 2016). Such high levels of GHG emissions can be attributed to the large expansion of the urban road network and automobile dependency in North America. It is very important to shift the paradigm and start planning our communities in a way that hinder automobile dependency and encourage people to use more sustainable modes of transportation. The fused grid model consists of several 16-hectare modules (ideally four) that provide vehicular accessibility for local traffic only and keep non-local traffic on the periphery of the modules while maintaining full pedestrian/cyclists accessibility via central green spaces and off-road pathways as shown in Figure 1. Perimeter roads in the fused grid model facilitate through traffic as per the following spacing: 1) collectors at 400 metres; 2) minor arterials at 800 metres; and 3) arterials at 1,600 metres. The classification, spacing, and alignments of the perimeter roads can be designed according to the existing ground conditions and planned land use activities. The model also provides convenient local services and amenities within a five-minute walking distance by classifying blocks located between the perimeter one-way couplet roads as mixed land use zones. All intersections in the neighbourhood are controlled by roundabouts or three-way intersections to reduce the severity of collisions. Several studies have been found in the literature that address the benefits of the fused grid model in various aspects including: safety (Sun and Lovegrove, 2013), traffic performance (IBI Group, 2007), walkability (Frank and Hawkins, 2007), and transportation modal share (Masoud et al. 2017). While previous research like Frank and Hawkins (2007) and Masoud et al. (2017) has concluded that applying fused grid principles will result in more walking and less driving, which obviously would result in reducing GHG emissions, none of the previous research quantified by how much would GHG be reduced and thus quantifying its social benefits.
There is a growing recognition of the relationship between patterns of urban land use and related levels of air pollutants (Abotalebi and Kanaroglou, 2015; Dimatulac & Maoh, 2016; Glaeser, 2011; Giuliano & Agarwal, 2011; Tyler, 2000; Zimmerman & Wiginton, 2016). The connection in this relationship is evolving land use patterns in Canada which have helped to encourage and sustain a dependency on motor vehicles. Consequently, Greenhouse Gas (GHG) emissions in Canada from the operation of motor vehicles increased by over one-third (35%) from 1990 to 2007, whereas the growth rate of population was less than 20% over the same period (Terefe, 2010).
As party to the 2016 United Nations Framework Convention on Climate Change’s Paris Agreement, Canada has committed to reducing its GHG emissions to 30% below 2005 levels by 2030. With transport there are two complementary approaches to help reach this reduction target. The first is to encourage a modal shift (Gullo & Rosales, 2016). In the urban context, this shift would be from motor vehicles to public transit, relying on policy options of full-cost pricing (e.g. tolling) and related land-use planning (e.g. Smart Growth, intensification). The second approach is to encourage more fuel efficient fleets. For the road motor vehicle fleet, this would entail a higher proportion of alternative fuel vehicles (AFV).
This study investigates the extent to which provincial vehicle registration files (VRF) can be used as a source of information to profile the road motor vehicle fleet by fuel type. Such a profile is critical as a benchmark going forward in order to track changes in the motor vehicle fleet composition. The paper begins with an overview of the relationship between transportation and urban form as well as the current contribution of the transportation sector to Canada’s GHG emissions. After describing the provincial VRFs, the paper defines a typology and then estimates the motor vehicle fleet by fuel type. We conclude with an examination of possible next steps in this effort.
Use of Reclaimed Asphalt Pavement (RAP) is beneficial to both road owners and builders as it allows for significant raw material cost reduction, while potentially maintaining expected pavement service life. In upcoming decades, the recycling of previously recycled pavements (i.e. re-recycling) will become widespread. There is currently little technical knowledge on how or how many times asphalt pavement can be recycled while sustaining its expected durability.
A novel asphalt binder aging method involving thin layers, heat, water spray, and UV radiation was developed to simulate approximately 20 years of in-service aging. The aged binder was recovered and blended with a softer, virgin binder. The blend was subjected to the next aging cycle. The process was repeated four times to simulate four recycling cycles (80 years) at 25 percent RAP addition. Three virgin binders were tested: standard Performance Grade (PG), one grade softer PG, and standard PG softened with paraffinic oil to one PG softer binder. Very detailed chemical and rheological analyses were performed to understand the impact of multiple recycling on irreversible chemical changes and evolution of rheological properties over the time. Results indicated that at moderate recycling levels, re-recycling is a viable option if an appropriate virgin binder is used.
The local geology of Prince Edward Island (PEI) primarily consists of material soft in nature that does not meet traditional aggregate specifications for the production of Hot Mix Asphalt (HMA) or other surface treatments. Therefore, roughly 95 percent of PEI’s HMA aggregates must be obtained and imported from off-Island sources. The associated work, expense, and environmental impact involved has raised the Department’s interest in the viability of asphalt recycling as a potential surface treatment option.
As a trial basis, the Department committed to recycling ten, one-kilometer sections of road ranging in classification from Local to Collector roads in 2016. Acceptance or rejection of the work was largely based on the ability of the Contractor to achieve the specified penetration values of the modified binder and visual inspection for defects, as well as requirements for cross slope, grade and joint construction of the completed HIR. The HIR process was constantly monitored in the field by Department staff and although not forming part of the specifications, properties such as compaction, smoothness, and asphalt cement content were monitored. This paper is an account of our experiences and lessons learned from the recent application of HIR undertaken within the Province of PEI.
Tack coat materials are used to provide sufficient bond between an existing asphalt concrete layer and a new asphalt concrete overlay and/or in-between two lifts of newly placed asphalt concrete. Most of the time, agencies and contractors rely solely on emulsified bituminous products for use as tack coats. Recent developments in tack coat materials are focusing on fast curing and non-tracking emulsions. The objective of this project is to evaluate the performance of several tack coat materials in Saskatchewan climate through a field study and a laboratory-testing program. Ten test sections were constructed in August 2017 on a two-way, two-lane rural highway (Highway 12) near Blaine Lake, Saskatchewan. Construction and installation of the tack coat materials was completed over two days to eliminate any variability due to weather conditions. A post-construction inspection was conducted in September 2017 to document any surface distresses related to the construction process. A distress survey will be conducted following the spring season of each year for 5 years. Core samples were collected in September 2017 to evaluate the initial bond strength of the tack coat materials. Core samples will be collected following the spring season of each year to evaluate the degradation of bond strength over time. Findings from this project will be used to update the approved tack coat materials list and provide recommendations and guidelines for construction best practices. This paper introduces the experiment, discusses the products used, and provides a summary of observations from the field component of the project.
Whether transportation engineers love it or are skeptical about it, emerging vehicle technologies have led an evolution converting traditional gasoline driven vehicles to connected vehicles, electrical cars, and autonomous vehicles.
Connected vehicles are already here in certain forms and reportedly by some to be fully functional by 2023. Today we communicate with other drivers around us and are connected to the world via the internet. The car manufacturer Volvo has announced that all their cars will be made electric in two years. In the progress of autonomous vehicles we are at level two or three out of the five levels of development as defined by the National Highway Traffic Safety Administration, with some optimists boasting that full automation can be achieved as early as 2025.
Irrespective, the question is not if but when transportation engineers will come face-to-face with such reality. The implications are profound. It will mean that transportation engineers need to equip themselves with new skills to avoid becoming obsolete. Universities will have to conduct researches in this area and to reassess their transportation curriculum to see if they are still relevant and sufficient. Professional organizations such as the Transportation Association of Canada (TAC) and the Institute of Transportation Engineers (ITE) may have to re-adjust their programs and change its agenda to suit the needs of the industry and their members. Government bodies and highway authorities must re-position themselves if they are to continue to function effectively. These agencies will be faced with the dilemma of how to balance the retrofitting of existing infrastructure with the construction of new facilities to allow the new breed of vehicles to operate smoothly.
Historically the study of transportation is a multi-disciplinary science but this emerging trend will bring it to a new and higher level. Future transportation engineers will be expected to have at least a working knowledge in areas such as information technology, communication science, computer algorithm, human factor safety engineering, public engagement, business and legal environments, and social media management. The knowledge which we have accrued in the past at universities such as geometric design, traffic flow theory, transportation planning, travel demand modeling, etc., may no longer be sufficient. Standards organizations will have to work on setting up protocol architectures that are interchangeable, interoperable and expandable. This paper explores the many issues facing the transportation engineers and the industry and discusses how best they should position themselves for the future. It sets the stage for further research. Commercial sectors including automobile manufacturers (hardware) and IT companies (software) are already on board. The time for transportation professionals to jump onto the bandwagon is now; and arguably not a moment too soon.
Drainage quality, as defined by AASHTO 1993, is affected by parameters related to subsurface materials properties as well as parameters related to roadway geometry. Hydraulic conductivity (permeability) of unbound granular materials (UGM) used in base and subbase layers construction is one of the major properties that influence drainage quality. This study investigates the variations in hydraulic conductivity and drainage quality resulting from modifying UGM gradation parameters. The considered UGM gradation parameters were porosity, fines content, and effective size of the blend. Field and laboratory testing of hydraulic conductivity were performed in order to quantify the benefits gained from basing UGM blends on performance related parameters. The test results were also used to investigate the reliability of the estimated hydraulic conductivity from the Moulton prediction model.
Several dense-graded UGM gradations of gravel were evaluated in this study. Permeability field testing was carried out on those gradations in multiple highway construction projects throughout Manitoba. The field testing utilized the double ring infiltrometer test for measuring the in-situ hydraulic conductivity of compacted base layers. In addition, UGM samples from each construction project were collected for further laboratory testing of hydraulic conductivity using the rigid-wall permeameter. Results from field and laboratory testing were used to provide performance-based range of values for drainage quality corresponding to the range of UGM gradation parameters investigated in this study. The measured hydraulic conductivity values were compared to values and prediction models reported in the literature for dense-graded UGM. Moulton’s hydraulic conductivity prediction model was found to provide an approximation of hydraulic conductivity values of the studied materials.
As per the five-year provincial roads plan (2017 edition), the Department of Transportation and Works of Government of Newfoundland and Labrador shifted its focus from the construction of new roads to the maintenance and rehabilitation of existing highways. With more than 270 km of road planned to be rehabilitated/upgraded in the province by 2022, appropriate strategies are needed to maintain and rehabilitate the roads. Many past studies reported that the life of overlays primarily depends on the interface condition between the existing pavement and overlay. In addition to this, the overlay fails mainly due to lack of proper maintenance for existing pavement before constructing the overlay. In this paper, Finite Element-based software program (ABAQUS) was employed to evaluate the interlayer damages between the existing pavement and overlay. Various interface conditions are modelled for evaluating the performance of the overlay. The results obtained from the analysis could help in selecting appropriate maintenance strategies for developing a sustainable overlay construction specification.
Merci à nos commanditaires premier
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