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Region of Peel – Commodity Flow and Network Analysis

Fri, 07/20/2018 - 20:40
Region of Peel – Commodity Flow and Network Analysis
by Lightstone,A; Duggal,M.
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 2017P06 - INTERNET


The Region of Peel is a significant freight hub for Canada and a strategic location for national freight distribution. An estimated $1.8 billion worth of commodities travel to, from and through Peel every day making goods movement a pillar of the regional economy. The Region of Peel is currently undergoing a goods movement planning effort, which includes development of a short term five year strategic plan and development of a long term plan. A component of the long term plan is the identification and assessment of supply chains of importance to the Region by commodity. The rise of online shopping or e-commerce, has forced retailers to seriously reconsider their logistics and distribution of their products. While brick and mortar stores are not disappearing, the need to rapidly deliver goods to both individual homes and stores for pick-up in response to online shopping necessitates a reappraisal of supply chain dynamics. As a result of the changing nature of last mile deliveries, technological changes, and decentralization of distribution, it is important for planning agencies to understand how the commodities of importance move through their jurisdiction. The commodity flow and network analysis completed for the long term plan allows Peel to understand the industries and commodities of greatest importance to the Region in terms of value and tonnage. Commodity attributes are identified using Ministry of Transportation Ontario (MTO) Commercial Vehicle Survey (CVS) data. The CVS data is used to identify the value, tonnage, and origin-destination of commodities. The movement of goods is modelled using the MTO Greater Golden Horseshoe Version 4 (GGHM V4) model in the 2011 base year and the forecast 2031 horizon year. The output of this analysis provides an understanding of how specific commodities move through the Region and the location of current and future congestion. It also provides an understanding of how industries interact with the Regional road network and how their supply chains function. Using this information, Peel can make future investments to benefit goods moving industries, the Region and nation.

Modeling Activity Scheduling Behavior of Individuals for Travel Demand Models

Fri, 07/20/2018 - 20:40
Modeling Activity Scheduling Behavior of Individuals for Travel Demand Models
by Hafezi,MH; Liu,L; Millward,H.
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 2017P05 - INTERNET


During the last decade or so in North America, activity-based travel demand modeling has become more popular than four-step and tour/trip travel demand models among urban and transport modelers. The disaggregation feature of activity-based models can help to capture different aspect of travel behavior complexity, such as flexibility in individual’s activity schedules, and associations between trips and activity participation. To date, researchers and practitioners have employed different approaches for development of activity-based models. A number of important specifications which affect the average level and variability of such models are prediction accuracy, reproducibility, computational time, large scale operation capability, and performance at the household level. The current paper presents cutting-edge methods and progress in developing a new comprehensive pattern recognition modeling framework for use in activity-based travel demand modeling. The framework leverages activity data to derive clusters of homogeneous daily activity patterns, in order to infer the scheduling behavior of individuals. In this paper, numerous new machine learning techniques are employed in the pattern recognition modeling framework. The pattern recognition model is applied to data from the large Halifax STAR household travel diary survey. The proposed modeling framework has much higher reproducibility and shorter computational time compared to other alternative modeling frameworks. Furthermore, the proposed modeling framework can be applied to any applications that contain a group of linked sequences, such as day-to-day variations in transit usage.

Optimizing Daily Travel Sequences and Time-Use Patterns of Individuals

Fri, 07/20/2018 - 20:40
Optimizing Daily Travel Sequences and Time-Use Patterns of Individuals
by Daisy,NS; Liu,L; Millward,H.
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 2017P04 - INTERNET


Activity-based models aim for a better understanding of people’s desires for, restraints on, and likelihoods to perform activities. They emphasize travelers’ participation in out-of-home activities, because people mostly travel to perform particular activities at different geographic places, rather than traveling just for the sake of travelling. Thus, travel demand is a by-product of the desire or need to participate in different activities. Since activities may take place at different geographic locations, traveling is required. Therefore, analyzing different people’s daily activity patterns in different localities will assist modeling of urban transportation demands. The notion of travel as an induced demand has been well established and accepted by researchers through the work of Oi and Shuldiner (1962), which suggests that one should study travelers’ participation in out-of-home activities first, before studying travel demand per se, as activities generate travel demand (Meyer and Miller, 2001). The set of activities performed by individuals each day is influenced by the choices and preferences of the individual as well as those of their household members, or social groups. Thus, agent-based models such as MATSim aim to obtain the optimal daily schedules so that existing activity travel behavior can be replicated, and future travel patterns can be predicted according to changes in activity timing or location. Construction of satisficing schedules that integrate the resources available for choices are the goal of optimal daily activity schedules. However, these models face challenges such as name and type of activities, sequence of activities, start and duration of activities, composition of the group participating etc. (Axhausen, 2011). Feil et al. (2010) developed a tabu-search based optimizer for the number and sequence of activities and proposed a recycling approach to overcome the computing time problems. Subsequently, Mahdieh (2017) proposed a bi-level optimization model where accuracy of the predicted model has been optimized in the upper level model and utility of participating in each activity has been optimized in the lower level model. Despite all the progress made in activity-based models, there are few studies that emphasize optimization of individual daily activity patterns. Thus, the aim of this study is to design and implement a prototype optimization model that efficiently optimizes a schedule, including the number, type, companionship, location, and sequence of its activities.

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.

Evaluation of Asphalt Pavement Crack Sealing

Thu, 07/12/2018 - 19:02
Evaluation of Asphalt Pavement Crack Sealing
by Carrick,K; Emery,J; Uzarowski,L.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P24 - MAIN


Crack sealing is one of the most commonly used routine maintenance treatments for road and airport asphalt pavements. Asphalt pavement performance monitoring shows that properly completed, timely crack sealing can significantly extend the service life of asphalt pavements. Recent practical experience in Ontario (road and highway pavements) and Newfoundland (airport pavements) shows that crack sealant failures (debonding) can occur in asphalt pavements that incorporate aggregates that are hard, brittle, and prone to stripping. This paper presents the results of extensive research on crack sealant performance in asphalt pavements, completed on several Canadian road and airport projects where poor crack sealant performance had been observed. It presents recommendations for changes in crack sealing methods to achieve improved pavement performance and more cost-effective asphalt pavement crack sealing.

Surface Slurry Sealing Systems in Canada: Performance and Practice

Thu, 07/12/2018 - 18:52
Surface Slurry Sealing Systems in Canada: Performance and Practice
by Crouteau,JM; Davidson,JK; Perrone,P.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P23 - MAIN


Traditional slurry seal systems were first used in Canada in the 1960s while polymer-modified systems were introduced in the early 1990s. Surface slurry sealing systems are placed to restore the surface characteristics of pavement or to preserve a pavement. The systems can be designed to correct rutting, to improve skid resistance, to seal and to protect the pavement surface. Skid Numbers for surface slurry sealing systems can reach the 50s, which, in terms of skid resistance, is exceptionally good. They can be applied on chip seals, on hot mix asphalt pavement or on concrete pavement. Surface slurry sealing systems are mixtures of cationic emulsified asphalt, mineral aggregates, mineral filler, water and additives, properly proportioned, mixed and spread with a machine over a properly prepared surface. A slurry mixture forms an impervious thin overlay over an existing pavement. The rate of application ranges from approximately 8.0 kg/m² for a non-polymer modified fine graded system to 18 kg/m² for a polymer coarse graded system. This paper presents an overview of the surface slurry sealing systems technology and a discussion on the state of the practice including design practices, construction procedures and the performance of these surface treatments.

Development of the Direct Tension Test Analysis Procedures for Thermal Crack Prediction

Thu, 07/12/2018 - 18:38
Development of the Direct Tension Test Analysis Procedures for Thermal Crack Prediction
by Rowe,GM; D'Angelo,JA; Ho,S; Sharrock,MJ.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P22 - MAIN


The PG binder grading system uses two temperatures to define the performance range. Initially the low temperature grade was determined using data from the Bending Beam Rheometer (BBR) and the strain at break from the Direct Tension Test (DTT). The strain at break was only used when the stiffness value at 60 s exceeded 300 MPa. The m-value had to be satisfied in either case. This scheme eliminated the strain at break requirement in the majority of the cases. An alternate procedure captures the pavement performance of a wide range of binders, including polymer-modified binders, more accurately. This procedure has been implemented in the AASHTO MP1A binder specification that requires computation of the critical cracking temperature from a determination of the thermal stress in the pavement from the binder relaxation modulus, E(t), which is calculated using BBR data. The DTT uses a ramp strain, enabling determination of E(t) directly. It may be used to compute the relaxation modulus master curve, eliminating the need for BBR tests. The calculations have been automated in the software TSAR Pro™. This paper describes the computation process adopted and compares results from the MP1 and MP1A procedures to this new method.

Accounting for Bias and Between-Laboratory Testing Differences

Thu, 07/12/2018 - 18:18
Accounting for Bias and Between-Laboratory Testing Differences
by Aurilo,V; Buttlar,WG; Manik,A; Shanley,L.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P21 - MAIN


Over the years many highway agencies in North America have made a valued commitment to End Results Specifications (ERS). As a direct result, it is believed that the quality of our roadways has improved. Material testing plays an important role in measuring this quality and is an integral ERS component. There are several common techniques used to quantify allowable differences in means between testing laboratories. However, there is currently no standard method which properly quantifies and removes inter-laboratory bias in setting these tolerances. This paper examines the bias between Quality Control and Quality Assurance laboratories and its impact on acceptance. Data from several projects in Canada and the United States are used to examine the components of testing variability in asphalt pavement construction and to separate the bias for further analysis, using a new statistical approach. Statistical formulations and case studies are presented to illustrate how implementation of the new methodology would impact current ERS protocols in North America. Among the case studies presented are several projects involving the Illinois Department of Transportation, where the current ERS specification utilizes contractor data in establishing percent-within-limits based pay factors.

Évaluation du PG 64-28 en vue de sélectionner se usages au Québec

Thu, 07/12/2018 - 18:02
Évaluation du PG 64-28 en vue de sélectionner se usages au Québec
by Leclerc,G; Paradis,M.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P20 - MAIN


Dès 1996, le ministère des Transports du Québec a adopté le système de classification des bitumes développé dans le cadre du Strategic Highway Research Program (SHRP). Les fournisseurs de bitume ont su s’adapter rapidement, et leurs procédés de fabrication sont en constante évolution depuis. Les caractéristiques d’un bitume de même classe de performance (PG) changent donc au fil des ans et c’est ce qui amène le Ministère à modifier, au besoin, ses recommandations sur le choix et la sélection des PG. À la suite de l’adoption du programme de classification SHRP, le MTQ a constaté que les bitumes produits étaient plus mous que ceux utilisés précédemment. Le MTQ a donc décidé de réévalué les propriétés des bitumes afin d’en vérifier l’impact sur le comportement des enrobés formulés avec ces bitumes et d’éviter de possibles contre-performances au niveau des chaussées routières. Les résultats obtenus à la suite des essais réalisés en laboratoire sur six PG 64-28 de fournisseurs ou de procédés différents, et sur des enrobés formulés avec ce PG, montrent que celui-ci pourrait remplacer avantageusement dans plusieurs situations le PG 58-28 et le PG 64-34 dans le sud-ouest de la province de Québec (zone 1). Bien entendu, avant de recommander quelques changements que ce soit, le MTQ devra valider les résultats obtenus en laboratoire par des planches expérimentales sur la route. L’utilisation du PG 64-28 sans polymère constitue une alternative moins coûteuse pour la plupart des types de routes et devrait contribuer à augmenter la durabilité des chaussées souples.

Properties of Recovered Binder Samples and their Relationships to Tank Binder

Thu, 07/12/2018 - 17:47
Properties of Recovered Binder Samples and their Relationships to Tank Binder
by Williams,RC; Kvasnak,A; Aurilo,V.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P19 - MAIN


A study was initiated in 2000 to determine whether a viable specification similar to the recovered penetration, conventionally used in the past by highway agencies, could be developed using the Superpave binder test methods. Sampling of 20 different paving projects from across the State of Michigan was done during the 2000 construction season. Material samples were obtained from three different locations: tank binders, hot mix asphalt trucks at the plant, and hot mix asphalt from behind the paver using plates. The sampling plan included mixes containing reclaimed asphalt pavement, polymer modified binders (SBS and SBR), and various performance graded binders. The properties of recovered plate samples compare well with tank binders as measured in a dynamic shear rheometer (DSR) and the stiffness using the bending beam rheometer (BBR). However, the population means were statistically different. Comparison of the m-values between sample types was generally poor. The truck sample properties were found to be overall weak in their relationship to tank sample properties. It is theorized that the noted differences are attributable to the incomplete removal of the solvent during the recovery process.

Advanced Study on the Rheological Behavior of a Composite Binder Treated Recycled Aggregate (Asphalt Emulsion and Cement)

Tue, 06/12/2018 - 19:41
Advanced Study on the Rheological Behavior of a Composite Binder Treated Recycled Aggregate (Asphalt Emulsion and Cement)
by Paquin,Y; Proteau,M.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P18 - MAIN

The 2001 Canadian Asphalt Exchange Program (CAEP) - 2001 Summary

Tue, 06/12/2018 - 19:21
The 2001 Canadian Asphalt Exchange Program (CAEP) - 2001 Summary
by Beshara,M.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P17 - MAIN


This report documents the results of the 2001 Canadian Asphalt Exchange Program. Nineteen agencies participated in the 2001 Canadian Asphalt Exchange Program. The exchange provides an opportunity for participants to compare their test results with those of other laboratories in order to provide a mechanism for reviewing and refining existing test procedures. The exchange also provides information to participants on their individual test procedures and equipment. Five types of binder material were tested in the 2001 exchange; a 150-200A asphalt cement, an MC-250 asphalt cutback, an HF 150S asphalt emulsion, an HF 150P polymer modified asphalt emulsion and a SHRP binder PG 58-28. All participants were given identical material samples to evaluate. The test result analysis was based on ASTM E691-92 “Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method”. This procedure was used to evaluate the repeatability and reproducibility standard deviations for the different test procedures performed in the asphalt exchange. This information was used to determine the 95 % repeatability and reproducibility limits for each test procedure. The analysis procedure also provided information for each participant to determine if their test results were consistent with those of the other laboratories.

The 2002 Canadian Asphalt Mix Exchange Program - 2002 Summary

Tue, 06/12/2018 - 19:15
The 2002 Canadian Asphalt Mix Exchange Program - 2002 Summary
by Beshara,M.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P16 - MAIN


Fifty-one Canadian engineering organizations participated in the 2002 CANADIAN ASPHALT MIX EXCHANGE PROGRAM. The exchange provides an opportunity for participants to compare their test results to those of other laboratories. It provides a mechanism for review and refinement of existing test methods and equipment. The exchange evaluates the volumetric and mechanical properties of an asphalt-aggregate mixture using Marshall Mix Design procedures, the gyratory compactor, and the ignition oven. This report documents the test results for the year 2002 Canadian Asphalt Mix Exchange Program.

Construction of Durable Longitudinal Joints

Tue, 06/12/2018 - 18:37
Construction of Durable Longitudinal Joints
by Scherocman,JA.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P15 - MAIN


The durability of longitudinal joints in asphalt concrete pavements is a major problem at many locations across North America. After a short period of time under traffic, these joints tend to ravel. In some cases the raveling is severe enough to completely erode the mix at the joint leaving a gap between the lanes. There are a number of factors during construction that directly affect the durability of a longitudinal joint. The first is the compaction of the unsupported edge of the first lane of mix placed. The second is the amount of overlap of mix on the second lane over the top of the first lane. The third factor is related to the raking of the mix at the joint. The final factor is the compaction of the mix at the joint. The construction of a longitudinal wedge joint is discussed. The need for the application of a tack coat on the joint, for cutting back the unsupported edge of the first lane and for paving in echelon in order to construct a hot joint are also discussed. Construction of a durable longitudinal joint is a question of good workmanship by the contractor using proper construction techniques.

Development of Flexible Pavement Roughness Prediction Models for Use in Network-Level Programming

Tue, 06/12/2018 - 18:22
Development of Flexible Pavement Roughness Prediction Models for Use in Network-Level Programming
by Ningyuan,L; Kazmierowski,T; Sharma,B.
2002.
Proceedings of the Forty-Seventh Annual Conference of the Canadian Technical Asphalt Association (CTAA): Calgary, Alberta.
CA6 AIH___ 2002P14 - MAIN


This paper describes the performance of flexible pavement observed on Ontario's highway network and the roughness prediction models developed for use in the Ministry of Transportation of Ontario’s (MTO’s) second generation Pavement Management System (PMS2). The PMS2 is used primarily for providing the Ministry’s senior management (decision makers) with a series of analysis reports and information related to pavement management, including annual pavement condition assessment, network pavement maintenance and rehabilitation needs analysis, cost-effective pavement preservation programming, and optimal investment strategy. A critical review of the Ministry's network level pavement performance database is presented, emphasizing pavement condition surveys, prediction models and main factors influencing assessment of long-term pavement performance. Several key issues related to quality control and quality assurance (QC/QA) of the pavement roughness measurement protocol are discussed with reference to roughness measurements and verification techniques used by the MTO. In addition, the paper discusses a pavement evaluation index in terms of International Roughness Index (IRI) and its application in needs analysis, multi-year pavement maintenance and rehabilitation projects programming.

Challenge of Permafrost Degradation Impact on Airport and Road Pavements

Mon, 06/11/2018 - 18:48
Challenge of Permafrost Degradation Impact on Airport and Road Pavements
by Uzarowski,L; Musial,M; Rizvi,R.
2018.
TAC 2018: Innovation and Technology: Evolving Transportation - 2018 Conference and Exhibition of the Transportation Association of Canada.
CA6 ARH_10 2018A5168 - INTERNET


A large part of northern Canada is in the discontinuous or scattered and discontinuous permafrost zone. It has been observed at airports and on roads, that due to disintegrating permafrost the pavements in the above zones exhibit rapidly progressing degradation. This paper describes cases where pavement failures due to melting or melted permafrost were investigated. Large settlements or slippage of airport pavements were observed. The pavements became very rough, posing a safety hazard to moving aircraft, particularly on runways. Similar settlement may occur on aprons and taxiways. In some cases airport buildings, including terminal buildings, may differentially settle/heave and require urgent expensive repairs. Relocation of buildings and airside groundside facilities may be necessary. Three cases are described in this paper where airport and road pavements exhibited serious problems due to permafrost degradation. It presents the method of investigation of permafrost presence and condition including visual condition inspection, geotechnical investigation and laboratory testing, temperature monitoring using thermistors and extent of permafrost using OhmMapping. The considered methods of addressing the issue of pavement failures included identifying the location and severity of the problem, addressing the drainage issues, emergency pavement repairs, soil replacements and pavement insulation, structural repairs using geosynthetics, and reconstruction including soil improvement or replacement, and relocation.

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