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Waiting for the Bus: Service Dependability and Commuter Mode Choice

Fri, 07/20/2018 - 20:40
Waiting for the Bus: Service Dependability and Commuter Mode Choice
by Tyndall,J.
2017.
Canadian Transportation Research Forum 52nd Annual Conference - Canadian Transportation: 150 Years of Progress//Les transports au Canada : 150 ans de progrès - Winnipeg, Manitoba, May 28-31, 2017.
CA6 AIP_10 2017P03 - INTERNET


Implicit in the decision to take a bus is the choice to accept the possibility of delay or uncertainty in journey duration. Frequent stops and the necessity to navigate urban traffic causes bus transit to be particularly susceptible to delays (Lin et al., 2008). The importance of providing reliable bus service in supporting bus patronage is well accepted in the theoretical literature (Bates et al., 2001). Rider surveys also support the hypothesis that bus reliability is important to patrons (Diab and El-Geneidy, 2012; Eboli and Mazzulla, 2007; Kou et al., 2017). Due to data limitations, empirical revealed preference (RP) analysis connecting observed vehicle reliability and bus mode choice have not been widely attempted. This paper will present detailed Automatic Vehicle Location (AVL) data on New York City (NYC) buses from 2016. Several previous studies have suggested metrics for transforming AVL data into dependability metrics (Bullock et al., 2005; Chen et al., 2009; Diab and El-Geneidy, 2012; Mazloumi et al., 2009; Uno et al., 2009). This study will estimate bus dependability statistics directly from a large AVL data set. Subsequently, the metrics will be taken to mode share data in order to relate bus dependability to local variation in bus ridership. Results suggest service dependability is an important determinant of local bus mode share amongst commuters.

Western Canadian Grain Transportation and the Maximum Revenue Entitlement: Process, Design Considerations and Final Implementation

Fri, 07/20/2018 - 20:40
Western Canadian Grain Transportation and the Maximum Revenue Entitlement: Process, Design Considerations and Final Implementation
by Pratte,S.
2017.
Canadian Transportation Research Forum 52nd Annual Conference - Canadian Transportation: 150 Years of Progress//Les transports au Canada : 150 ans de progrès - Winnipeg, Manitoba, May 28-31, 2017.
CA6 AIP_10 2017P02 - INTERNET


The transportation of Western Canadian grain and the role of federal rate regulation have a long and well-documented relationship that reaches back to the settling of Western Canada and the establishment of the Crows Nest Pass Agreement in 1897. The ‘crow rate’ and its statutory freight rates was later formalized in 1927 and remained static for almost nine decades, until November 1983 when it was superseded by the Western Grain Transportation Act (WGTA), which took effect January 1, 1984 and the era of the ‘crow benefit’ subsidy and the setting of more compensatory maximum freight rates.1 The WGTA was repealed in 1995 and the Canada Transportation Act took effect on July 1, 1996, bringing an end to direct transportation subsidies but continuing the government’s role in setting maximum freight rates. In a reaction to a period of grain transportation difficulties experienced in 1995-96, an intense period of focus, investigation and consultation on the state of the Western Canadian grain handling and transportation system (GHTS) would be launched by government. The result of this two years of work would culminate in several months of frenetic policy and legislative activity that moved the regulatory framework governing the GHTS to less regulated (but by no means complete) and more commercialized environment. This paper surveys the way in which decades of economic regulation of the GHTS, specifically rate setting regulations in the form of the maximum rate cap gave way to the Maximum Revenue Entitlement (MRE) regulation at the turn of the last century. Specific consideration is given to the way in which the specific recommendations of the Estey Report (1998) and the Kroeger Report (1999) on this issue were viewed by the government of the day and would ultimately culminate in Bill C-34, that amended the Canada Transportation Act and implemented the final form of the MRE on August 1, 2000.

Rail Capacity, Freight Rates and Removal of the Maximum Revenue Entitlement Program

Fri, 07/20/2018 - 20:40
Rail Capacity, Freight Rates and Removal of the Maximum Revenue Entitlement Program
by Torshizi,M; Gray,R.
2017.
Canadian Transportation Research Forum 52nd Annual Conference - Canadian Transportation: 150 Years of Progress//Les transports au Canada : 150 ans de progrès - Winnipeg, Manitoba, May 28-31, 2017.
CA6 AIP_10 2017P01 - INTERNET


In the review of the Canadian Transportation Act submitted to the Minister of Transport in December 2015 it is argued that the Maximum Revenue Entitlement (MRE) program “act as barriers to investment and productivity improvements in the broader rail system”. The review anticipates the total removal of the MRE regulation within seven years. This will have profound impacts on the industry stakeholders including grain companies and producers. To a great extent, these impacts will depend on the grain movement levels and service charges in the new environment. This study explores the railways’ incentives for moving Western Canadian grain to export positions without the MRE regulation in place. In a spatial-temporal partial equilibrium model we estimate the railways’ revenue-maximizing movement levels and the welfare implications for grain producers, shippers, and the railways under several scenarios. Results indicate that removing the MRE may create a perverse incentive for the railways to increase their revenue by increasing freight rates. The grain companies will have to share a great portion of their rents with the railways that control the most scarce resource in the grain handling and transportation system.

Canadian Transportation Research Forum 52nd Annual Conference - Canadian Transportation: 150 Years of Progress//Les transports au Canada : 150 ans de progrès - Winnipeg, Manitoba, May 28-31, 2017

Fri, 07/20/2018 - 20:40
Canadian Transportation Research Forum 52nd Annual Conference - Canadian Transportation: 150 Years of Progress//Les transports au Canada : 150 ans de progrès - Winnipeg, Manitoba, May 28-31, 2017
2017.
Canadian Transportation Research Forum 52nd Annual Conference - Canadian Transportation: 150 Years of Progress//Les transports au Canada : 150 ans de progrès - Winnipeg, Manitoba, May 28-31, 2017.
CA6 AIP_10 2017P01-51 - INTERNET

Pedestrian Crossing Control Guide, Third Edition

Tue, 07/17/2018 - 20:37
Pedestrian Crossing Control Guide, Third Edition
by Montufar,J; Patmore.K; Bahar,G.
2018.
CA6 ARH_65 2018P21 - MAIN


Walking is a vital activity which requires suitable infrastructure as a core element in the provision of a sustainable, equitable, and safe transportation system. Pedestrian crossing control presents a challenge for traffic engineers, urban planners, road designers, and others given the need to accommodate pedestrians safely in an interactive manner with other users of the transportation system. The Pedestrian Crossing Control Guide is primarily intended to augment the information about pedestrian crossing control devices and their applications contained in the Manual of Uniform Traffic Control Devices for Canada (MUTCDC). The main objective of this Guide is to promote uniformity across the country with respect to the approach used in the provision of pedestrian crossing control. This is done through the development of a decision support tool to assist in the decision-making process when establishing the need for controlling the traffic to enable pedestrians to cross the roadway safely and identifying the type of traffic control device that would be most suitable for the location’s cross section, vehicular exposure, and pedestrian demand.

Safety Evaluation of Signalized Restricted Crossing U-Turn Intersections

Sat, 06/02/2018 - 20:33
Safety Evaluation of Signalized Restricted Crossing U-Turn Intersections
by Hummer,JE; Rao,S.
2017.
US1 DTH680 2017S36 - MAIN


This study evaluated restricted crossing U-turn (RCUT) intersection and was conducted by the DCMF program for the Evaluation of Low-Cost Safety Improvements Pooled Fund Study. RCUT is defined as a three-approach or four-approach intersection where minor street left-turn and through movements (if any) are rerouted to one-way downstream U-turn crossovers. RCUTs are also known as superstreets, J-turns, reduced conflict intersections, and synchronized streets. Previous research has shown that unsignalized RCUTs are generally safer than conventional options. However, there are no known studies specific to the safety of signalized RCUTs. The objective of this effort was to collect and analyze crash data to develop a crash modification factor (CMF) for signalized RCUTs. This study collected and analyzed crash data before and after conversion of 11 intersections from conventional to RCUT design. The intersections were in suburban areas on four- or six-lane arterials. For most individual sites and groups of sites examined, odds ratio tests showed that there were high-quality comparison sites available, and regression to the mean was not an issue. The project team recommends a CMF of 0.85 for overall crashes and 0.78 for injury crashes for the conversion of a conventional intersection to an RCUT intersection. Based on those CMFs, the project team produced an estimated benefit-to-cost ratio of 3.6 to 1.0 when considering safety and operations or 2.6 to 1.0 considering safety only.

Safety Evaluation of Edge-Line Rumble Stripes on Rural Two-Lane Horizontal Curves

Sat, 06/02/2018 - 20:25
Safety Evaluation of Edge-Line Rumble Stripes on Rural Two-Lane Horizontal Curves
by Himes,S; Gross,F; Persaud,B; Eccles,K.
2017.
US1 DTH680 2017E26 - MAIN


The Development of Crash Modification Factors (DCMF) program conducted safety evaluations of edge-line rumble stripes (ELRSs) on rural two-lane horizontal curves for the Evaluation of Low-Cost Safety Improvements Pooled Fund Study. This study evaluated the application of ELRSs on rural two-lane horizontal curves. ELRSs are a variation of common shoulder rumble strips used to alert drowsy or distracted drivers when they are leaving the travel lane to the right. ELRSs are installed with the edge-line pavement marking placed directly over the rumble strip. Geometric, traffic, and crash data were obtained at treated rural two-lane horizontal curves in Kentucky and Ohio. To account for potential selection bias and regression-to-the-mean, an empirical Bayes before–after analysis was conducted using reference groups of untreated rural horizontal curves with similar characteristics to the treated sites. The analysis also controlled for changes in traffic volumes over time and time trends in crash counts unrelated to the treatment. Owing to a small sample for the reference group in Kentucky and a simultaneous statewide curve warning sign upgrade program in Ohio, alternative reference sites were used to account for annual trends. The results for Kentucky indicated statistically significant reductions for total, injury, run-off-road (ROR), and nighttime crashes, with crash modification factors (CMFs) of 0.75, 0.64, 0.74, and 0.63, respectively. The results for Ohio indicated statistically significant reductions for all crash types, with total, injury, ROR, nighttime, and nighttime ROR CMFs of 0.79, 0.79, 0.78, 0.75, and 0.71, respectively. The two States’ results could not be combined because of the statewide curve signing program in Ohio. It is important to note that all crash types considered in this research excluded intersection-related and animal crashes. Benefit–cost (B/C) ratios were estimated to be 331:1 for Kentucky and 477:1 for Ohio. If ELRSs were used as a curve-specific treatment, the B/C ratio would likely be much smaller because of the higher installation cost; however, these results suggest that the treatment can be highly cost effective.

Ontario Must Prepare for Vehicle Automation Part 2: How Skilled Governance Can Influence its Outcome

Fri, 05/25/2018 - 18:36
Ontario Must Prepare for Vehicle Automation Part 2: How Skilled Governance Can Influence its Outcome
by Grush,B; Niles,J; Schlecter,B.
2017.
CA6 ARG750 2017O55 Part.2 - MAIN|INTERNET


This report recommends that our regional and municipal bus transit authorities move from an acquire-and-operate mode to one of specify-and-regulate. There are two key and menacing drawbacks to an acquire-and-operate approach. First, we are entering an era in which technology is changing faster than any government agency can respond, meaning that the risk associated with choosing, acquiring and deploying rapidly innovated automated transportation systems becomes untenable. A March 2017 staff report from the Toronto Transit Commission illustrates this, as detailed in this report. Second, the cost of new systems, new infrastructure and attrition of existing systems is out of taxpayer reach without commercial involvement if we are to move dramatically away from household car ownership. Finally, this report recommends a way to specify and regulate growing fleets that is focused entirely on optimization and inclusion. This involves licensing regulated operators to manage fleets under government social-performance criteria. These fleet operators would be free to innovate vehicles, services and prices — subject to safety, privacy and security certification. Beyond performance criteria and certifications, this approach represents an all-digital market system managed via fees and subsidies based entirely on social performance metrics. It is critical that all segments of urban society be served by this “new mobility.”

Ontario Must Prepare for Vehicle Automation: Automated vehicles can influence urban form, congestion and infrastructure delivery

Fri, 05/25/2018 - 18:36
Ontario Must Prepare for Vehicle Automation: Automated vehicles can influence urban form, congestion and infrastructure delivery
by Grush,B; Niles,J; Baum,E.
2016.
CA6 ARG750 2016O55 Part.1 - INTERNET


The purpose of this report is to look at why and how government agencies and public interest groups can and should influence the preferred types and deployment of automated vehicles and the implication of related factors for planning.

Safety Evaluation of Multiple Strategies at Stop-Controlled Intersections

Thu, 05/24/2018 - 19:33
Safety Evaluation of Multiple Strategies at Stop-Controlled Intersections
by Le,T; Gross,F; Persaud,B; Eccles,K; Soika,J.
2018.
US1 DTH680 2018S12 - MAIN


The Development of Crash Modification Factors program studied the safety performance of various stop-controlled intersections for the Evaluation of Low-Cost Safety Improvements Pooled Fund Study. This study evaluated the safety effectiveness of multiple low-cost treatments at stop-controlled intersections. Improvements included basic signing and pavement markings. This strategy is intended to reduce the frequency and severity of crashes at stop-controlled intersections by alerting drivers to the presence and type of approaching intersection. Geometric, traffic, and crash data were obtained at three- and four-legged, two- and four-lane major road, and urban and rural stop-controlled intersections in South Carolina. To account for potential selection bias and regression to the mean, an empirical Bayesian before–after analysis was conducted, using reference groups of untreated intersections with similar characteristics to the treated sites. The analysis also controlled for changes in traffic volumes throughout time and time trends in crash counts unrelated to the treatments. The aggregate results indicate reductions for all crash types analyzed (i.e., total, fatal and injury, rear-end, right-angle, and nighttime). The reductions are statistically significant at the 95-percent confidence level for all crash types. For all crash types combined, the crash modification factors (CMFs) are 0.917 for all severities and 0.899 for fatal and injury crashes. The CMFs for rear-end, right-angle, and nighttime crashes are 0.933, 0.941, and 0.853, respectively. The benefit–cost ratio estimated with conservative cost and service life assumptions is 12.4 to 1 for total crashes at unsignalized intersections. The results suggest that the multiple low-cost treatments, even with conservative assumptions on cost, service life, and the value of a statistical life, can be cost effective

The Road to Vision Zero: Zero Traffoc Fatalities and Serious Injuries

Wed, 05/23/2018 - 18:36
The Road to Vision Zero: Zero Traffoc Fatalities and Serious Injuries
by Calibaba,J.
2017.
CA7 FAT150 2017R58 - MAIN


Vision Zero is a priority road safety framework for Canada, as outlined by the Canadian Council of Motor Transport Administrators (CCMTA) in the release of their Road Safety Strategy 2025 (RSS 2025). The strategy, released in 2016, focuses on the long term of ensuring Canada’s roads are the safest in the world, while adding a greater focus on the vision of “towards zero” serious injuries and fatalities on the roadways. The Vision Zero Advocate Institute, supported by ATS Traffic, is the market leader in Vision Zero. Current studies point to a clear disparity in municipal comprehension and implementation of Vision Zero initiatives. The Vision Zero Advocate Institute closes that gap. (from the introduction)

Performance of a Trial Section Reconstructed Using Cellular Concrete in the City of Edmonton

Thu, 05/10/2018 - 19:38
Performance of a Trial Section Reconstructed Using Cellular Concrete in the City of Edmonton
by Donovan,H; Kanji,F; Dolton,B.
2018.
TAC 2018: Innovation and Technology: Evolving Transportation - 2018 Conference and Exhibition of the Transportation Association of Canada.
CA6 ARH_10 2018A5143 - INTERNET


Over the past two decades, roadways in several residential neighborhoods within northeast Edmonton have experienced significant early structural failures. Failures were so severe in some cases that heavy vehicles (i.e. garbage and fire trucks) were not able to access some affected streets. These failures occurred as a result of the presence of subgrade soils that are susceptible to water softening, poor subgrade drainage, and additional water drainage from private sump pumps. As a consequence, The City of Edmonton has established an extensive roads program that conducts annual replacement of roadways in northeast Edmonton. As part of the above-noted roads replacement program, two trial sections were selected by The City of Edmonton to be reconstructed in 2009. These sections were located in adjacent cul-de-sacs to provide for comparison of performance between two constructions methods. One section was constructed using a traditional granular section, and the other used lightweight cellular concrete (LCC) as a subbase material. LCC is a construction material formed by mixing a cement and water slurry with a pre-formed foam, similar in consistency to shaving cream. The material is produced onsite and pumped into place using proprietary pumping equipment that may be setup several hundred meters from the pour area. The LCC supplied for the above-noted projects had a wet (cast) density of 475 kg/m3, which is approximately one-fifth the density of typical granular subbase. As a result of the high percentage of air bubbles (approximately 72% by volume), the material also has insulating qualities that, depending on the applied thickness, can reduce or prevent frost heave and subsequent thaw weakening of subgrade soils. Load-deflection data was gathered on the trial sections for both pre and post construction conditions using The City of Edmonton’s Dynaflect system. The City performed additional testing in 2016 using both its Dynaflect and Falling Weight Deflectometer systems. The results of this testing are presented in this paper. Since reconstruction, no maintenance activities have been required for either the granular or cellular concrete trial sections.

Nouvelles chartes d’épandage au ministère des Transports, de la Mobilité durable et de l’Électrification des transports pour réduire les effets de l’épandage des sels de voirie sur l’environnement

Thu, 05/10/2018 - 19:17
Nouvelles chartes d’épandage au ministère des Transports, de la Mobilité durable et de l’Électrification des transports pour réduire les effets de l’épandage des sels de voirie sur l’environnement
by Noël,S.
2018.
TAC 2018: Innovation and Technology: Evolving Transportation - 2018 Conference and Exhibition of the Transportation Association of Canada.
CA6 ARH_10 2018A5142 - INTERNET


Le ministère des Transports, de la Mobilité durable et de l’Électrification des transports entretient un vaste réseau routier durant la période hivernale. À l’exception du réseau local (107 000 km), dont la responsabilité incombe aux municipalités du Québec, les routes relevant de la compétence du Ministère représentent près de 31 000 km. Ce réseau est entretenu en grande partie par le secteur privé (66 %) alors que la portion restante est répartie entre les équipes opérationnelles du Ministère (20 %) et les municipalités (14 %). Durant la saison froide, quelque 800 000 tonnes de sel de voirie sont épandues annuellement sur le réseau du Ministère, occasionnant des effets préjudiciables à la flore, à la faune, à la qualité de l’eau, aux sols et aux infrastructures à des degrés divers. Au Québec, le suivi de la qualité de l’eau de plusieurs lacs en périphérie urbaine démontre que, dans certains cas, les concentrations en chlorure augmentent de façon continue. Pour de plus rares cas, les concentrations dépassent même le seuil de toxicité chronique pour la vie aquatique. Considérant que le chlorure de sodium a des impacts documentés sur l’environnement et les infrastructures routières, il apparaît primordial d’en faire une utilisation et une gestion responsables.

Non-Destructive Testing for Optimizing Concrete Pavement Rehabilitation

Thu, 05/10/2018 - 18:53
Non-Destructive Testing for Optimizing Concrete Pavement Rehabilitation
by Al-Abbasi,A; Shalaby,A.
2018.
TAC 2018: Innovation and Technology: Evolving Transportation - 2018 Conference and Exhibition of the Transportation Association of Canada.
CA6 ARH_10 2018A5141 - INTERNET


Visual inspection is the state-of-practice in deciding the type and location of repairs in road rehabilitation projects. Field non-destructive testing (NDT) can provide information on pavements performance to help make such decisions. NDT was carried out on City of Winnipeg’s regional roads. The projects included two rigid pavements and one composite structure and they were scheduled for rehabilitation in 2017. Falling Weight Deflectometer (FWD) testing was performed prior to and after milling and full-depth repairs to evaluate the effect of the asphalt overlay on load transfer efficiency, as well as the improvement in joint performance achieved by full-depth repairs. Real Time Kinematic (RTK) surveying equipment was used to capture coordinates of test locations for retesting after milling or full-depth repairs. This study also evaluates how pavement deflection measurements can be incorporated at the design stage to facilitate the decision making process and to optimize rehabilitation costs with the availability of joint performance information. Hundred fifty joints were tested in total and their performance was evaluated through their load transfer efficiency, peak deflection and differential deflection between the approach and leave slabs at the joint. It was found that load transfer efficiency measurement experienced a considerable reduction once the asphalt overlay was milled. This means that testing concrete joints performance before milling overestimates their performance and could lead to different repair decisions. Joints generally achieved over 90% load transfer efficiency following a full-depth repair. In cases where the load transfer efficiency was low after a full-depth repair, the peak and differential deflections were found to be small. This highlights the importance of including peak and differential deflection criteria in evaluating performance. Moreover, it was found that in one project approximately 22% of tested joints were under-performing in terms of load transfer efficiency, while 50% of them received full-depth repair. The cost of such repair could have been optimized with the availability of such information. This study sheds light on the benefits of FWD information in the decision making process of joint repairs.

Machine Learning Powered Roadside Asset Extraction using LiDAR

Thu, 05/10/2018 - 17:53
Machine Learning Powered Roadside Asset Extraction using LiDAR
by Makehmir,R; Coram,C; Firbank,D; Palsat,B; Palesch,D.
2018.
TAC 2018: Innovation and Technology: Evolving Transportation - 2018 Conference and Exhibition of the Transportation Association of Canada.
CA6 ARH_10 2018A5140 - INTERNET


Traditionally, road assets are monitored and inventory controlled getting direct access to each asset, which can be very time-consuming and requires numerous field recordings and trained personnel. With recent advancements in data collection technologies, vehicle-based data collection platforms can collect millions of data points from all spatial directions at highway speed per second. The big data incorporates LiDAR point clouds, 360o degree imagery, and Laser Crack Measurement Sensor data. This paper presents the development of an innovative advanced machine learning algorithm capable of extracting roadside assets including traffic signs, guardrails, line painting, and rumble strips from the big database. The machine learning process starts with training steps in which hundreds of thousands of training datasets are used and then tested against the testing dataset. Once the testing database has passed at 99% or more, the trained program is ready to detect that asset. The techniques used to train machine learning algorithms to extract signs from the LiDAR database are developed using unsupervised clustering algorithm followed by auto-classification using machine learning classifiers with imagery. A similar approach has been taken to identify other assets such as guardrails, rumble strips, and line paintings. This process has been able to successfully identify and classify traffic signs from highways as well as urban and rural roads. The developed machine learning algorithm is programmed in parallel and performed at typical highway operation speed. Additional information about the geometry and retro-reflectivity properties are other important features that are also calculated and reported by this algorithm. The developed algorithm has been in production phase in the British Columbia Ministry of Transportations Asset Management project, in more than 13000 km of highways and has been able to pass all quality assurance mechanisms. This paper outlines the steps followed to develop a roadside asset extraction machine learning algorithm from the LiDAR and imagery database, as well as present a sample of the resultant roadway traffic sign asset database.

LiDAR or Imagery - Which to Choose?

Thu, 05/10/2018 - 17:30
LiDAR or Imagery - Which to Choose?
by Davis,K.
2018.
TAC 2018: Innovation and Technology: Evolving Transportation - 2018 Conference and Exhibition of the Transportation Association of Canada.
CA6 ARH_10 2018A5139 - INTERNET


Over the past few years there has been extensive innovation in Geospatial technologies that can be used in revolutionary new ways in order to accurately and efficiently map and assess transportation assets. Significant investments in R&D and the race amongst auto manufacturers towards making connected and autonomous vehicles a reality has been instrumental in facilitating a rapid evolution of how spatial data is collected, processed and turned into usable intelligent transportation asset information. There are a number of sensors and information systems that transportation asset managers can leverage in order to manage their assets. Amongst this plethora of technologies, both LiDAR and Imaging provide some of the most important and accurate foundational mapping information regarding the assets and features in the transportation sector. Advanced sensor technologies in combination with artificial intelligence, machine learning and integrated information systems provide significant opportunities for improvements and efficiencies in the collection of data as it relates to transportation asset management. This presentation will discuss some of the differences between LiDAR and Imaging, some of the different systems that are being used to collect these different types of spatial data and how transportation asset information is accurately and effectively extracted and derived from each type of data that these respective technologies produce.

Leader in You

Thu, 05/10/2018 - 17:15
Leader in You
by Ladwar,K.
2018.
TAC 2018: Innovation and Technology: Evolving Transportation - 2018 Conference and Exhibition of the Transportation Association of Canada.
CA6 ARH_10 2018A5138 - INTERNET


The workforce is changing. Thoughtful work is being done around succession planning in our ministry and throughout government – this has led to a deliberate and planned approach to addressing changes. The Ministry of Transportation and Infrastructure has developed an action oriented Succession Committee with a Vision to “Motivate.Transfer.Transform.: Building talent for the future.” The mandate of the committee is to build a culture of shared responsibility for succession by influencing our organization to recruit, develop and retain a strong and diverse team within the BC public service. As part of the ministry’s ongoing succession initiatives, it is critical that we continue to empower and provide our people with the resources and skills to be a resilient workforce for the future. To achieve this, one major element identified though employee consultation was leadership.

Development and Evaluation of a Non-Tracking Asphalt Emulsion for Tack Coats and Fog Seals

Fri, 05/04/2018 - 20:42
Development and Evaluation of a Non-Tracking Asphalt Emulsion for Tack Coats and Fog Seals
by Kucharek,AS; Esenwa,M; Varamini,S; Bickle,E; Cormier,A.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P15 - MAIN


Tack coats are thin applications of asphalt emulsion between the layers of a pavement structure with the role of enhancing adhesion. Fog seals are thin emulsion applications to pavement surface for protecting the surface from oxidation and water ingress, as well as reducing the risk of raveling and stone loss. One of the downsides of using asphalt emulsions for these applications is the required breaking and curing time. Even after curing, traditional emulsion grades will track onto nearby surfaces. Slow curing fog seals require longer road closures and/or a light sand application before trafficking. This paper presents the development stages of a non-tracking emulsion developed for bond coats and fog seals. The emulsion was formulated and engineered to be fast curing and provide a hard, non-tracking surface, suitable to support traffic without the use of sand application. Its tracking properties were assessed using novel tracking and curing tests, and its performance as a bond coat was measured using the tack coat shear test developed by McAsphalt. Trial projects of tack coating and fog seals were conducted from 2013 to 2016 throughout several Canadian provinces. Performance to date in the field, as well as some observed challenges, are presented.

Predicting HMA Fatigue Using the Double Edge Notched Tension Test and Multiple Stress Creep Recovery Test

Fri, 05/04/2018 - 20:11
Predicting HMA Fatigue Using the Double Edge Notched Tension Test and Multiple Stress Creep Recovery Test
by Aurilio,M; Mikhailenko,P; Baaj,H.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P14 - MAIN


Fatigue resistance is an important factor for high quality Hot Mix Asphalt (HMA). Asphalt cements containing higher concentrations of polymer are known to be more strain tolerant, which can provide improved fatigue resistance in HMA. Use of polymer modified asphalt cement is a proven way to improve fatigue performance. Many municipalities and the Ontario Ministry of Transportation have implemented the Double Edge Notched Tension (DENT) test to improve the fatigue performance of the asphalt cement and the corresponding HMA. The DENT test is performed at an intermediate temperature that should correspond with fatigue performance. The Multiple Stress Creep Recovery (MSCR) test is an environmental test that measures the compliance and elastic response of an asphalt binder. The MSCR test is conducted at the high-performance grade temperature based on the local 7-day maximum temperature. The results from this research have shown that there is no clear relationship between increasing concentration of polymer modification and DENT performance. On the other hand, the percent recovery showed a very good correlation with polymer modification and performance. Based on the information presented in this paper, the MSCR is ultimately expected to be validated by HMA fatigue testing while the DENT is not.

Safety Evaluation of Red-Light Indicator Lights at Intersections

Tue, 05/01/2018 - 19:27
Safety Evaluation of Red-Light Indicator Lights at Intersections
by Himes,S; Gross,F; Persaud,B; Eccles,K.
2017.
US1 DTH680 2017S16 - MAIN|INTERNET


The Development of Crash Modification Factors program conducted the safety evaluation of red-light indicator lights (RLILs) at intersections for the Evaluation of Low-Cost Safety Improvements Pooled Fund Study. This study evaluated safety effectiveness of RLILs. RLILs are auxiliary lights mounted on signal heads, mast arms, or poles that are directly connected to a traffic-control signal. The RLIL activates at the onset of the red phase and allows an enforcement officer to observe red-light running from downstream of the intersection. This strategy is intended to reduce the frequency of crashes resulting from drivers disobeying traffic signals by providing a safer and more efficient means for police to enforce the red interval. Geometric, traffic, and crash data were obtained at treated four-legged signalized intersections in Florida. To account for potential selection bias and regression-to-the-mean, an empirical Bayes before–after analysis was conducted using reference groups of untreated four-legged signalized intersections with characteristics similar to those of the treated sites. The analysis also controlled for changes in traffic volumes over time and time trends in crash counts unrelated to the treatment. Results indicate statistically significant crash reductions for most crash types. Disobeyed signal crashes had an estimated crash modification factor (CMF) of 0.71. Total crashes, fatal and injury crashes, right-angle, and left-turn crashes had estimated CMFs of 0.94, 0.86, 0.91, and 0.60, respectively. The benefit-cost ratio estimated with conservative cost and service life assumptions was 92:1 for four-legged signalized intersections. The results suggest that the treatment, even with conservative assumptions on cost, service life, and the value of a statistical life, can be cost effective. In addition to the crash-related benefits, RLILs can improve the efficiency and safety of red-light running enforcement efforts. While this study did not evaluate the efficiency and safety impacts with respect to enforcement, it should be noted that RLILs do allow police to observe violators from a downstream position, eliminating the need for a second observer (upstream) and the need to pursue a violator through the red light.

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