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12-Year Performance Review of Bloomington Road (York Region Road 40) Rehabilitation Rehabilitation using Cold In-Place Recycling and a 6.7 mm Fine Stone Mastic Asphalt

Wed, 04/04/2018 - 20:46
12-Year Performance Review of Bloomington Road (York Region Road 40) Rehabilitation Rehabilitation using Cold In-Place Recycling and a 6.7 mm Fine Stone Mastic Asphalt
by Moore,T; Farashah,MK; Esenwa,M; Varamini,S; Kucharek,AS.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P13 - MAIN


Bloomington Road, Regional Highway 40 in the Regional Municipality of York, serves as a major artery for vehicles accessing Highway 404. The section under review between Kennedy Road and Highway 48 was built in 1969 and rehabilitated with an innovative pavement design in 2005. Prior to rehabilitation, the asphalt surface was severely oxidized with extensive thermal cracking, however, the longitudinal and transverse profiles of the roadway were in relatively good condition and there was no sign of major structural failures. Rehabilitation of the roadway consisted of Cold In-Place Recycling (CIR), a Heavy-Duty Asphalt Binder Course (HDBC) Hot Mix Asphalt (HMA), and a 6.7 mm rut-resistant fine-graded Stone Mastic Asphalt (SMA). This paper provides a review of the design and construction details for the pavement lifts, as well as material and process selection details. Special consideration is given to the curing of the CIR and the rut resistance of the SMA lift. This paper also presents a long-term field performance evaluation of the rehabilitated pavement section with quantified in-situ performance by means of field observations, laboratory evaluations of retrieved pavement specimens, and semi-automated pavement performance data survey collected by York Region over twelve years of in-service pavement life.

Using Complex Modulus (E*) Test to Evaluate Moisture Damage of Hot Mix with Glass Aggregates

Wed, 04/04/2018 - 19:38
Using Complex Modulus (E*) Test to Evaluate Moisture Damage of Hot Mix with Glass Aggregates
by Lachance-Tremblay,E; Vaillancourt,M; Perraton,D; Di Benedetto,H.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P12 - MAIN


Evaluation of the moisture damage of HMA is normally conducted on loose aggregate coated with binder or on HMA compacted samples; both methods having their respective disadvantages. Those tests are empirical and are susceptible to give misinterpretation of moisture damage. The complex modulus test for asphalt mixtures, also known as the dynamic modulus, characterizes the mixtures Linear Visco-Elastic (LVE) properties. This paper presents a method used at LCMB to evaluate the moisture damage of HMA samples based on LVE measurements. Two reference mixtures and three mixtures with glass aggregates were tested. One set of samples contained hydrated lime as an anti-stripping additive. First, the LVE properties of the samples were evaluated in a dry condition. Then, the samples were saturated with water and cured into a water bath at 60 deg C for 14 days and evaluated again. Overall, complex modulus test is very effective at evaluating the moisture damage of asphalt samples. This method has multiple advantages and many analysis options, which make it very interesting to evaluate moisture damage. Moreover, it was found that hydrated lime is a very effective anti-stripping additive. For some of the mixtures with anti-stripping agent, water soaking had little effect on the LVE properties.

Comparison of New Test Methods and New Specifications for Rutting Resistance and Elasticity of Modified Binders

Thu, 03/29/2018 - 21:37
Comparison of New Test Methods and New Specifications for Rutting Resistance and Elasticity of Modified Binders
by Moraes,R; Swiertz,D; Bahia,H.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P11 - MAIN


There is no consensus among state highway agencies as to the appropriate binder specifications required for adequate quality control and acceptance of modified binders. Supplemental tests have been adopted in addition to standard Performance Grade (PG) tests and are often referred to as “PG+” procedures. The Multiple Stress Creep and Recovery (AASHTO M332) test has been proposed to replace the AASHTO M320 for PG grading of binders. However, some agencies are concerned that asphalt binder formulation will change after adopting the new system, while others are unsure how to relate the current M320 grades to the new S, H, and V grades. In this study, testing of a large number of binders was completed and correlations between results of “PG+” test and MSCR tests were performed. Regarding the MSCR test, results show that the %R parameter is a good candidate to detect the presence, and potentially the quantity, of elastomeric modification. However, using universal limits for the MSCR %R parameter that are dependent on Jnr values in not practical nor useful since current binder formulations are controlled differently by agencies. Furthermore, no logical equivalency of M320 PG grades to M332 traffic grades was identified, so changes to binder formulations are anticipated.

Investigation of the Tensile Strength of Hot Mix Asphalt Incorporating Pulp Aramid Fiber

Thu, 03/29/2018 - 21:37
Investigation of the Tensile Strength of Hot Mix Asphalt Incorporating Pulp Aramid Fiber
by Saliani,SS; Carter,A; Baaj,H; Badeli,S.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P10 - MAIN


Premature cracking of flexible pavements is a very common problem in Canada. Nowadays, it is common to use several types of additives and modifiers to asphalt binders and asphalt mixes to improve their performance and increase the service life of flexible pavements. In order to mitigate pavement cracking, the asphalt mixes used in the pavement structure need to have a high resistance to fatigue or thermal cracking according to their position in the pavement structure. Several studies reporting on the use of fibers in asphalt concrete have been found in the literature. The objective of this project is to study the impact of the addition of Pulp Aramid Fiber (PAF) to Hot Mix Asphalt (HMA) in terms of mix design and indirect tensile strength. The optimum asphalt content of the fiber mixes is first determined and then the impact of fiber on their volumetric properties is investigated. Finally, the behavior of PAF in HMA is characterized by indirect tensile testing at different conditions. PAF mixes showed better ductility, even at lower temperatures, than the control mix. Therefore, PAF would lead to an improvement of the resistance to low temperature cracking and would delay crack propagation in the mix.

A Review of Distress and Roughness Performance Models in Nova Scotia's Pavement Management System

Thu, 03/29/2018 - 21:37
A Review of Distress and Roughness Performance Models in Nova Scotia's Pavement Management System
by Hegazi,M; Marlin,A; Whieley-Lagace,L.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P09 - MAIN


Nova Scotia Transportation and Infrastructure Renewal (NSTIR) implemented its pavement management system (Highway Pavement Management Application or HPMA) in 2008. NSTIR conducts annual pavement condition surveys on their highway network. Data collected includes International Roughness Index (IRI), which is used to calculate a Roughness Index (RI). Surface distress data is also collected to calculate a Distress Index (DI). The RI and DI are combined into an overall Pavement Quality Index (PQI). In 2016, NSTIR initiated a project to review their pavement prediction models. Differences in historical data trends were noted during the initial model review. These differences were thought to be a result of technological advancements in data collection equipment. The study examined the existing roughness and distress indices to determine if and/or how changes in data collection technology have impacted the measured pavement condition. The investigation included a review of the historical roughness and distress data. Based on this data review, changes were made to the roughness and distress models to better reflect current NSTIR data and conditions. A feedback analysis was then conducted on the prediction models to conduct performance modeling on the HPMA. This paper details the data investigation and updated models.

Detailed Evaluation of Select CIR Projects in Alberta

Thu, 03/29/2018 - 21:37
Detailed Evaluation of Select CIR Projects in Alberta
by Sharma,V; Johnston,A; McMillan,C; Khan,A; Grell,D.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P08 - MAIN


Alberta Transportation has completed rehabilitation of a number of highway sections using Cold In-place Recycling (CIR) and Full Depth Reclamation (FDR) over the years. In order to better understand the mechanism responsible for the formation of transverse cracks (specifically to see if transverse cracks are reflecting from the underlying pavement) and the susceptibility of the recycled material to moisture induced damage, Alberta Transportation retained Tetra Tech to undertake pavement inspections and analysis of selected projects rehabilitated using CIR and FDR. A total of five highway segments rehabilitated with CIR and one highway segment rehabilitated with FDR were included in the study. The study included a review of background information, visual crack mapping, pavement inspection using Ground Penetrating Radar, asphalt pavement coring, determination of moisture content in the CIR portion of the cores, and visual assessment of the cores to identify the progression and type of cracks. The key objectives were to investigate the performance of the pavements rehabilitated with CIR in terms of transverse crack formation and moisture susceptibility. This paper discusses the completed evaluation and findings from the study and further expands on Alberta Transportation’s experience with CIR, as presented at the 2016 CTAA Conference.

RAP Paving - British Columbia Perspective

Thu, 03/29/2018 - 21:37
RAP Paving - British Columbia Perspective
by Sharma,V; Johnston,L; Hogg,B; Schmidt,A; Van Reekum,A.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P07 - MAIN


The British Columbia Ministry of Transportation and Infrastructure (MoTI) has been using 100 percent Reclaimed Asphalt Pavement (RAP) to pave numerous side roads in its network for more than 15 years with mixed results. The RAP is typically transported off site and recycled by adding a rejuvenator and processing the material through a pugmill. The cold recycled mix is then transported to site and placed using conventional paving equipment as a wearing surface – a surfacing layer of Hot Mix Asphalt (HMA) is not placed. Although the BC MoTI has been using this procedure for over a decade, no study to evaluate the addition rate of the rejuvenator, mix design, recycling process, or testing to determine the quality of the recycled mix was ever completed. The crushed granular equivalency or structural layer coefficient of the recycled mix was also never developed. This paper will document the findings of a laboratory program undertaken to evaluate the optimum addition rate of the rejuvenator, curing period prior to the placement of the recycled mix, and compaction criteria, as well as the structural layer coefficient and crushed granular equivalency of the recycled RAP. A case history of several previously completed projects using cold recycled RAP pavement are also presented.

Creating Economical and Well-Performing Binders via Modification by Epoxidized Plant-derived Oil Materials

Thu, 03/29/2018 - 21:37
Creating Economical and Well-Performing Binders via Modification by Epoxidized Plant-derived Oil Materials
by Podolsky,JH; Hernandez,N; Williams,RC; Cochran,EW.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P06 - MAIN


Asphalt binders produced at refineries are becoming stiffer due to an ever-increasing demand for more expensive lighter and heavier fraction products such as gasoline, jet fuel, and lube oils. To increase output of lighter fractions and heavy gas oils, refineries have gone through upgrades producing higher amounts of stiffer asphalt binders such as Vacuum Distillation (VD) tower, Solvent De-Asphalting (SDA), and Residuum Oil Super critical Extraction (ROSE) unit bottoms. Materials used to soften/repair stiff asphalt binders are known as fluxes. Through recent work at Iowa State University, great potential was seen for epoxidized plant oil materials as fluxes/rejuvenators. Within this work two epoxidized plant oil products derived from soybeans, EBS and EMS were manufactured and used for modifying three stiff asphalt binders produced from VD tower, SDA and ROSE units. A full Superpave binder investigation found that improvement in low temperature performance was greater than improvement in high temperature performance for the SD and ROSE unit bottoms when using either EBS or EMS. It was also found that substantial decreases in costs, fuel usage, and emissions could be gained through the use of EBS and EMS in the production of asphalt mix.

Mixture Design and Field Experience: Coloured Hot Mix Asphalt on Bus Rapid Transit (BRT) Lanes in Ontario

Thu, 03/29/2018 - 21:37
Mixture Design and Field Experience: Coloured Hot Mix Asphalt on Bus Rapid Transit (BRT) Lanes in Ontario
by Varamini,S; Esenwa,M; Tighe,SL; Farashah.MK; Moore,T.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P05 - MAIN


The Regional Municipality of York, in collaboration with Metrolinx (an agency of the Government of Ontario), has implemented Bus Rapid Transit (BRT) lanes along the three most heavily travelled roads in York Region. To enhance visibility and assist motorists when navigating this new transit system, a special red-coloured asphalt mixture was employed as a surface layer. The colour was achieved by using a selected aggregate bland, colouring pigment, and specially formulated asphalt mixture. This paper provides information on steps employed in the design of coloured asphalt mixture such as: 1) selection of performance graded asphalt cement suitable for the Region’s climatic conditions and traffic loadings, 2) designing an aggregate blend to match the desired colour, ) performing a volumetric analysis for the special Hot Mix Asphalt to meet physical requirements of Superpave 12.5 FC2, and 4) performance testing to capture the impact of pigment on the mixture’s strength and durability at different in-service temperatures. Performance testing was performed at the Centre for Pavement and Transportation Technology located at the University of Waterloo. Production and paving experience with the coloured asphalt mix are also included in this paper, as well as field performance in terms of manual and automated distress survey.

Regina Bypass Project's Innovative Asphalt Pavement Structures

Thu, 03/29/2018 - 21:37
Regina Bypass Project's Innovative Asphalt Pavement Structures
by Proteau,M; Pouteau,B; Berrada,K; LeBec,S; Heath,D.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P04 - MAIN


Currently in progress, the “Regina Bypass” highway project involves the construction of approximately 45 km of a new four-lane highway (greenfield), the rehabilitation of more than 18 km of Highway 1 (brownfield), and 5 km of reinforcement works on an existing section. The project is being realized using a “Design-Build-Finance-Operate-and-Maintain” (DBFOM) approach and it will be operated by the concessioners group until late October 2049. Taking into account the specific physical and climatic constraints involved, as well as the concession’s duration, flexible pavements have been designed using several innovative concepts such as a mechanistic pavement design approach to the structural pavement design, the use of engineered asphalt mixes, the use of on-site recycling process for existing sections, and the installation of performance monitoring stations. This article provides a summary of the numerous laboratory tests required for the study of the engineered asphalt mix formulations specifically developed for this project, and it describes the follow-up program that will measure their performance with time.

Impacts of Flooding on Asphalt Pavements under Climate Change

Thu, 03/29/2018 - 21:37
Impacts of Flooding on Asphalt Pavements under Climate Change
by Lu,D; Tighe,SL; Xie,WC.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P03 - MAIN


Flooding has been identified as the most frequently occurring natural hazard in Canada. Extreme weather events, such as floods and extreme precipitation events, are increasing in intensity and frequency under climate change. The impact of flooding on asphalt pavements has become a rising concern, since pavements are designed based on historical data, which do not adequately reflect current and future climate. Therefore a comprehensive understanding of the flooding impacts o pavements is of great importance for improving their resilience. The objective of this study is to establish an assessment framework for the impacts of flooding on asphalt pavements through fragility analysis, and conduct case study to illustrate the approach. Flood characteristics, pavement damage patterns, damage components, and performance impact factors are investigated. Thirty-six extreme precipitation scenarios with various magnitudes, durations, and numbers of event cycles are loaded to two typical asphalt pavement structures in Southern Ontario by using MEPDG. Then, a probabilistic pavement fragility modeling method is developed for generating fragility functions, which integrate flood hazards, pavement structure, pavement performance, and damage states. Results show that the loss of pavement life is not negligible due to extreme events. Fragility functions and curves are able to demonstrate the probability of exceeding certain pavement damage given flood hazards.

Base Asphalt Variability: An Opportunity for the Development of Innovative Characterization Approaches

Thu, 03/29/2018 - 21:37
Base Asphalt Variability: An Opportunity for the Development of Innovative Characterization Approaches
by Delfosse,F; PLanche,JP; Largeaud,S; Drouadaine,I; Turner,F.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P02 - MAIN


American and European refiners have been going through phases of revamping and rationalization to maximize the flexibility in crude oil supply while matching their production models and refining tools. For users of asphalt, this has created concerns about the quality and consistency of the delivered asphalt binders, especially as the current specifications appear insufficient to ensure satisfactory performance of the finished products. In this context, the search for relationships and correlations between asphalt properties and the performance of the asphalt mixtures and the pavement has become very relevant. The study presented here was dedicated to identifying and quantifying such relationships. It focused on asphalt mixes made with unmodified asphalts. It was based on a standard mix design with one type of aggregate, and involved 14 paving grade asphalts from various origins. The characterization of asphalt mixes covered various performance characteristics from resistance to rutting and fatigue to thermal cracking. The compositional analysis of binders included the most advanced fractionation method SAR-AD™ and a chemometrics analysis using a new software to identify and develop the correlations. Both were developed by the Western Research Institute (WRI). Significant correlations were found tying binder chemical composition metrics to binder mechanical characteristics to asphalt mix characteristics.

Managing the Transition to Driverless Road Freight Transport

Thu, 03/01/2018 - 16:45
Managing the Transition to Driverless Road Freight Transport
by Veryard,D.
2017.
ZZ IEM_22 2017M17 - INTERNET


This report explores how a transition to driverless trucks could happen. Reduced reliance on humans to move road freight offers many benefits. It also threatens to disrupt the careers and lives of millions of professional truck drivers. Based on different scenarios for the large-scale introduction of automated road freight transport, this study makes recommendations to help governments manage potential disruption and ensure a just transition for affected drivers.

Guide de gestion des charges pour les chaussées à faible capacite

Fri, 02/16/2018 - 21:27
Guide de gestion des charges pour les chaussées à faible capacite
by St. Michel,G; Reggin,A; Kavanagh,L.
2017.
CA6 ARH_90 2017L55Z - MAIN


Le Guide de gestion des charges pour les chaussées à faible capacité fournit une synthèse de pratiques canadiennes et internationales pour gérer les structures de chaussée à faible capacité dans des climats nordiques. Le guide inclut une série de pratiques exemplaires recommandées pour gérer ces chaussées en période de gel et de dégel ainsi que la gestion des chaussées tout au cours de l’année. Une base économique pour effectuer des décisions en matière de gestion des charges pour les chaussées à faible capacité est présentée dans le Guide. Le document renferme un cadre de soutien pour la prise de décision, qui peut être adapté pour toute administration routière canadienne afin de les aider à prendre des décisions économiquement justifiées et de restreindre les charges sur les structures de chaussée à faible capacité.

Lignes directrices nationales sur la sécurité en zone de travaux routiers au Canada

Fri, 02/16/2018 - 21:27
Lignes directrices nationales sur la sécurité en zone de travaux routiers au Canada
by Rempel,G; Montufar,J; Patmore,K; Bahar,G; Smiley,A.
2016.
CA6 ARH_60 2016W59Z - MAIN


Il est nécessaire d’élaborer une source nationale de lignes directrices pour venir en aide aux organismes canadiens et à leurs entrepreneurs qui doivent créer des zones de travaux routiers sécuritaires pour les travailleurs et le grand public (une attention particulière devant être accordée aux usagers vulnérables de la route). Bien que ces lignes directrices doivent promouvoir des normes standard, elles doivent aussi demeurer flexibles pour tenir compte des facteurs politiques, législatifs et fiscaux uniques à chaque administration gouvernementale et reconnaître les différents codes de la route des provinces. De plus, les lignes directrices doivent être sensibles aux pratiques en zone de travaux routiers dans les États américains à proximité, vu l’interconnectivité des réseaux de transport canadiens et américains. Ce projet a donc pour but l’élaboration de lignes directrices encourageant l’utilisation de pratiques cohérentes au Canada en matière de zones de travaux routiers pour les routes de classifications différentes et en milieux différents (rural/urbain/suburbain, été/hiver, jour/nuit, etc.), les vitesses d’exploitation typiques (sans zone de travaux), les vitesses d’exploitation souhaitables (dans une zone de travaux – travailleurs sur place ou non), les débits et la composition de la circulation (par ex., les motos, véhicules commerciaux, etc.), l’âge des groupes d’usagers, l’aménagement du territoire adjacent, les conditions temporaires et variables de la chaussée (par ex., le frottement des pneus et la surface de contact avec des surfaces différentes pour les automobiles, les scooters, les motocyclettes, etc.), de même que la longueur et la durée de la zone de travaux routiers. La charge de travail des usagers de la route (dont les conducteurs et les usagers vulnérables de la route) ainsi que les attentes feront partie des lignes directrices. Les deux tâches principales du projet sont les suivantes : a) définir et résoudre les lacunes en matière de pratiques au Canada; et b) concevoir un ouvrage de référence encourageant l’uniformité nationale en ce qui concerne les usagers vulnérables de la route, la planification de la gestion, la gestion et la documentation des incidents, les audits de sécurité routière en zone de travaux (avant et pendant les activités dans la zone de travaux), ainsi que les détours et la gestion des actifs (dont l’accommodement des usagers vulnérables de la route). On s’attend à ce que ce document encourage une pratique plus uniforme en matière de sécurité en zone de travaux routiers au Canada dans différentes conditions d’exploitation. Ces lignes directrices fourniront des outils additionnels qui contribueront à une communication claire et uniforme aux usagers de la route en zones de travaux routiers. La pratique uniforme jette les bases sur lesquelles reposent les attentes des usagers de la route dans les zones de travaux routiers et leur habileté à répondre de façon appropriée selon leur expérience dans des situations semblables. La sécurité en zone de travaux routiers devrait s’améliorer à mesure que le contenu des présentes lignes directrices sera adopté et intégré aux pratiques municipales et provinciales à la grandeur du pays.

Canadian Guide to Traffic Calming

Fri, 02/16/2018 - 21:27
Canadian Guide to Traffic Calming
by Solomon,H; Malone,B; Garcia,J; Bottesini,G; Hoeun,S; Chartier,G.
Second Edition.
2018.
CA6 ARH_65 2018C13 - MAIN


The Canadian Guide to Traffic Calming presents traffic calming as a method to reduce the speed and/or volume of non-local traffic infiltrating into neighbourhoods. The Guide explains principles of traffic calming, suggests a process for introducing and implementing traffic calming, and describes the applicability, effectiveness, and design principle for a wide range of traffic calming devices. The devices are categorized in terms of vertical deflection, horizontal deflection, roadway narrowing, surface treatment, pavement markings, access restriction, gateways, enforcement, education, shared space, and emerging technologies and measures.

Author’s Closure: Comments on "Longitudinal Thermal Cracking Phenomenon: Thermal Imaging Detection and Laboratory Case Studies"

Mon, 02/05/2018 - 21:15
Author’s Closure: Comments on "Longitudinal Thermal Cracking Phenomenon: Thermal Imaging Detection and Laboratory Case Studies"
by Lavoie,M.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P28 - MAIN


The paper provides final comments from the original lead author of the paper entitled "Longitudinal Thermal Cracking Phenomenon: Thermal Imaging Detection and Laboratory Case Studies," which was published in the proceedings of the CTAA 61st Annual Conference. The author of the original paper would like to acknowledge the detailed response submitted by Mr. Brown, Consultant Engineer. The comments make it possible to revive the discussions on the importance of improving the homogeneity of asphalt laying. The definition criterion of the Ministere des Transports, de la Mobilite durable et de l’Electrification des transports (MTMDET) concerning thermal streaks includes the therm “thermal” with reference to the type of measure used, regardless of the type of segregation that generates this thermal signature. Since the defects in the distribution of the asphalt are not easily identifiable, thermal imaging, allowing the detection of thermal streaks and the possibility of seeing the effects of paver’s adjustments, is the ideal tool to reduce risks of longitudinal cracking in asphalt pavements.

Discussion Paper: Comments on "Longitudinal Thermal Cracking Phenomenon: Thermal Imaging Detection and Laboratory Case Studies"

Mon, 02/05/2018 - 21:04
Discussion Paper: Comments on "Longitudinal Thermal Cracking Phenomenon: Thermal Imaging Detection and Laboratory Case Studies"
by Brown,A.
2017.
Proceedings of the Sixth-Second Annual Conference of the Canadian Technical Asphalt Association (CTAA): Halifax, Nova Scotia.
CA6 AIH___ 2017P27 - MAIN


The authors present a very complete paper with excellent laboratory data on the properties of a physically segregated mix and point out the problems associated segregated mix in terms of performance. They have also shown that non-destructive thermal imaging carried out as the mat is laid can effectively locate physical segregation. However, type of segregation they highlight in this paper is not related to the temperature of the mix. In this Author’s opinion, this is physical segregation caused by the irregularities in the flow of material under the screed. It can be detected with thermal imagery but it cannot be resolved or prevented by the techniques used to address thermal segregation.

Paver la voie: technologie et le futur du véhicule automatisé.

Fri, 02/02/2018 - 20:33
Paver la voie: technologie et le futur du véhicule automatisé.
Le Comité sénatorial permanent des transports et des communications.
2018.
CA1 AA_100 2018D61Z - INTERNET


À la demande du ministre des Transports, le Comité sénatorial permanent des transports et des communications a mené une étude intitulée « La technologie des véhicules automatisés et son avenir : Paver la voie » portant sur les questions techniques et réglementaires liées à l’arrivée des véhicules branchés et automatisés (c.-à-d. sans conducteur). Le Comité a entendu 78 témoins venant du Canada et des États-Unis, a reçu un bon nombre de mémoires écrits de la part des différents secteurs touchés et a assisté à de nombreuses démonstrations de cette technologie qui évolue rapidement. Le Comité a formulé 16 recommandations à l’intention du gouvernement fédéral. Nous croyons que ces recommandations contribueront à établir une stratégie nationale coordonnée sur les véhicules automatisés et branchés.

Driving Change: Technology and the future of the automated vehicle

Fri, 02/02/2018 - 20:25
Driving Change: Technology and the future of the automated vehicle
Senate Standing Committee on Transport and Communications.
2018.
CA1 AA_100 2018D61 - INTERNET


At the request of the Minister of Transport, the Standing Senate Committee on Transport and Communications undertook this study, “Driving Change: Technology and the Future of the Automated Vehicle”, on the regulatory and technical issues related to the deployment of automated (i.e. driverless) and connected vehicles. The Committee heard from over 78 witnesses from across Canada and the United States, received a number of written submissions from various sectors involved, and participated in many impressive demonstrations of this quickly developing technology. The Committee is making 16 recommendations to the federal government, recommendations we believe will help build a coordinated national strategy on automated and connected vehicles.

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