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Ontario’s Multimodal Province-Wide Model: Validation, Challenges and Data Gaps

Tue, 11/21/2023 - 19:05
Ontario’s Multimodal Province-Wide Model: Validation, Challenges and Data Gaps
by Chowdhury,T; Nateghinia,E; Khan,RE; Damodaran,S.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5127 - INTERNET


The Ontario Ministry of Transportation (MTO) uses an integrated, multimodal passenger and freight forecasting model for the province in long-range planning and to support various applications such as corridor-level highway planning and design, highway project prioritization and modal studies. This model – termed Transport and Regional Economic Simulation of Ontario, TRESO – is a multimodal macroscopic model, used to forecast person and freight transportation demand throughout the province of Ontario. This model connects five key components, namely: a macroeconomic model that is spatially disaggregated, person travel models dealing with urban as well as inter-urban/long-distance travel by residents and visitors, freight models that deal with commodity flows by main modes of rail, marine, intermodal and truck flows on the road, and the underlying “supply-side” common element of the transportation network. The focus of this paper is “model validation”, which is a process through which model outputs for the base year are compared with observed data to gauge how well a model represents the reality. This paper discusses the details of validation of different components of the TRESO model, data used to perform such validation, while pointing out the data gaps. Validation efforts focus on the following key areas: modeled road network volumes versus traffic count; use of GPS data to compare network performance; long-distance rail passenger demand compared to rail ridership data, and; urban transit travel demand compared to transit ridership data for major urban areas of Ontario. The paper concludes with key observations from the analysis, key challenges, and potential areas of improvements in future model re-calibration and validation exercises.

Ontario's Tow Zone Pilot: Safer and Faster Clearance of Highway Incidents

Tue, 11/21/2023 - 18:52
Ontario's Tow Zone Pilot: Safer and Faster Clearance of Highway Incidents
by Graham,T.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5126 - INTERNET


Collisions and breakdowns along major freeways can result in partial or full closures for extended periods of time. This creates significant queues and delays that often contribute to secondary collisions and impacts to the movement of people and goods. As noted in the 2023 Ontario Budget: Building a Strong Ontario, congestion in the Greater Toronto Hamilton Area (GTHA) currently costs the economy more than $11 billion in lost productivity. Highways in the GTHA are among the busiest in North America, carrying an Average Annual Daily Traffic (AADT) volume of 450,000 vehicles. Therefore, collisions and other incidents impacting traffic have a tangible impact to the economy. For example, a two-hour delay where all lanes are closed can result in an economic impact of $1M to $2M (Source: MTO Traffic Office). Providing towing and recovery services on high-speed provincial highways can be dangerous. To ensure safe and faster clearance there is a need to ensure that towing and recovery operators providing services on provincial highways are properly trained, equipped, and integrated with other emergency response entities. Following extensive collaboration between MTO, the Ontario Provincial Police (OPP) and industry stakeholders, MTO launched a Tow Zone Pilot (TZP) on December 13, 2021, that introduced four (4) restricted towing zones on sections of provincial highways in the GTA where only authorized towing companies are allowed to provide towing and recovery services. The primary goals of the pilot are to enhance safety, reduce clearance times, and support the safe and efficient movement of people and goods on some of North America’s busiest highways. The pilot includes equipment, performance and storage requirements that are designed to improve safety, response, and clearance times, and ensure customer protection. The pilot is planned for a duration of up to four (4) years and to date has been performing well. To measure program performance the pilot team carries out extensive data analysis to ensure that the goals and objectives of the pilot are being achieved. During the first fiscal year of the program (April 1, 2022, to March 31, 2023), more than 31,000 tow-related incidents were serviced, and MTO staff have made concerted efforts to progressively improve performance in areas identified as Key Performance Indicators. As a result, response and clearance times have progressively improved and currently meet target parameters on average more than 85% of the time. Customer complaints are another important indicator of performance; they amount to less than 1% of total incidents. The pilot has provided additional benefits including better and more integrated towing and recovery services during severe winter weather events. As part of MTO’s commitment towards continuous improvement, the TZP is reviewed, and adjustments are made on an on-going basis in alignment with the goals and objectives of the program. MTO continues to work in partnership with the OPP, industry partners, insurance companies, municipalities, and other stakeholders to build on the successes of the pilot.

MTO Reference Materials for Control, Calibration and Development of Soil and Aggregate Test Methods

Tue, 11/21/2023 - 18:34
MTO Reference Materials for Control, Calibration and Development of Soil and Aggregate Test Methods
by MacDonald,CA; Jiang,Z.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5125 - INTERNET


The Ministry of Transportation of Ontario (MTO) has been actively involved in developing and establishing reference materials for soil and aggregate test method development, as well as test method control and calibration for over 35 years. The primary function of these materials is test method control and calibration for the critical purpose of ensuring the highest quality testing in support of durable Ontario infrastructure. Many of MTO’s reference materials have been cited and used in test methods and publications by ASTM, CSA, RILEM, and numerous other internationally recognized research publications over the years. Many applied, practical and experimental research projects that are engaged in test method development and innovative technologies development are requestors of MTO’s reference materials. These projects are normally in need of control materials with established or “known” parameters and/or established field performance to use in support of their research programs. MTO has historically both directly and indirectly greatly benefitted from this external research as a result of the practice of providing control materials. This paper provides an overview of MTO’s reference material program including its development and evolution. MTO’s new reference material code system is presented, as well as the procedure for requesting materials and MTO’s policies for making materials available to requestors. A summary of the different reference materials currently available and their intended usage, such as which materials are used for control and calibration for which test methods, will be provided. There will be mention of the historical reference materials, that although may be commonly recognized, are now out of stock and no longer available, e.g., the “Brechin Aggregate”. The newer materials that have superseded and replaced these historic ones are detailed, e.g., “Drain Brothers Stoney Lake”. Currently there are ten to twelve different reference materials that are either actively in use and/or are in the process of being established for future use. Commonly known names for some of these materials include Spratt #3, Pittsburg, Sudbury Gravel, Dresden Clay, etc. Reference material summaries include each material’s physical and engineering property test ranges as well as descriptions of each material’s field performance and geological environment of origin, where available. The chemistry and petrography for each is also included where available.

Monitoring the Post Construction Structural and Environmental Behaviours of an Instrumented Smart Pavement Section

Tue, 11/21/2023 - 18:15
Monitoring the Post Construction Structural and Environmental Behaviours of an Instrumented Smart Pavement Section
by Ceric,M; Oyeyi,AG; Wang,S; Tavassoti,P; Baaj,H; Maadani,O; Shafiee,M.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5124 - INTERNET


Pavement infrastructure worldwide is pivotal to successful economic growth. However, like all infrastructure, it requires proper Maintenance and Rehabilitation (M&R) strategies and evidence-based Pavement Management Systems (PMS) to ensure that the pavement condition can meet the desired level of service under the impact of traffic loads and given climatic loading parameters. With the improvement of new paving materials, climate change and extreme weather events impacts solely relying on traditional M&R techniques, where monitoring periods are scheduled sporadically, may not be enough to understand pavement's performance and their mechanistic response to varying loading and climatic conditions. However, pavement design and management can benefit from the concept of Smart Pavements, considering the recent advances in Artificial Intelligence (AI) and instrumentation monitoring systems. This study presents a summary of the current progress for the “smart pavements” concept currently being implemented within a section of a major two-lane arterial roadway in Kitchener, Ontario. The goal is to enable pseudo-real-time monitoring of the section and understand the actual in-situ responses through advanced instrumentation and by running Machine Learning models to improve our understanding and prediction of long-term pavement performance. Thus far, the installation and construction of the instrumented section have been completed, and preliminary results have been obtained. This paper presents the preliminary pavement environmental and structural behaviours immediately after the construction of the section, as well as five months after construction. The instrumentation installed in each layer consists of horizontal and vertical asphalt concrete strain gauges, moisture probes, pressure cells, and temperature strings. The impact of asphalt temperature right after construction until service condition and loading frequencies on the structural behaviors of the pilot section were monitored through several rounds of known weight axial truck. The results are used to establish a baseline for better interpretation of the pavement structure during its in-service monitoring period.

Modelling the Impacts of Rebalancing Strategies on Bike Share Toronto

Tue, 11/21/2023 - 16:28
Modelling the Impacts of Rebalancing Strategies on Bike Share Toronto
by McNee,S; Miller,EJ.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5123 - INTERNET


Bike Share Toronto is a docked bike share system (“System”) that operates within the City of Toronto. It began operating in 2011 and has expanded to include 625 stations as of June 2022. This paper uses a microsimulation model of the System to examine the operational challenge of rebalancing bike share networks. Using simulations of the System’s operation each day in 2021, this paper compares the impact of three different rebalancing scenarios upon rebalancing operations in the system. The three scenarios cover: (a) the “as is” condition using observed rebalancing operations; (b) a worst-case scenario where no rebalancing operations are conducted, and (c) an optimized scenario where rebalancing operations are planned with perfect knowledge of ridership patterns. The optimized scenario offers a theoretical maximum efficiency to better understand how operations could be improved. The results of the model’s analysis show that the number and length of delays where a user must relocate to another station due full or empty stations decrease dramatically between the worst-case scenario and the “as is” scenario. Under the optimized scenario, users experience fewer delays and the tour lengths of the trucks performing rebalancing operations are 36% lower than in the “as is” scenario. These results highlight the potential for improved forecasting, route planning and rebalancing to reduce the System’s operating costs and improve user experience.

Ministry of Transportation of Ontario Quiet Pavement Studies

Tue, 11/21/2023 - 16:04
Ministry of Transportation of Ontario Quiet Pavement Studies
by Li,J; Leung,F; Lee,S.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5122 - INTERNET


In 2009, Ministry of Transportation of Ontario (MTO) initiated a study on the effectiveness of using different asphalt mix types in reducing noise arising from the tire-pavement interaction at the source. Five trial asphalt sections were constructed in October 2009 on Highway 405 in the Niagara Region. In 2015, MTO Eastern Region also conducted a quiet concrete pavement study to compare NGCS (Next Generation Concrete Surface) pavement with several conventional transversely tined concrete pavements. On Board Sound Intensity (OBSI) measurements were conducted according to AASHTO TP76-12 on a total of nine (9) sections of Highways 115, 417, 401 and 410. In 2022, MTO Pavements Section undertook another OBSI noise study on seven (7) test sections along Highways 401, 402 and 404 located in Western and Central Regions. These studies generally used asphalt mix sections as controls, consisting of Superpave 12.5 FC2 or SMA 12.5 (Stone Mastic Asphalt) asphalt surface mixes. The remaining sections were concrete sections of varying ages with different surface texture treatments such as grooving, tining or a combination thereof. From the studies conducted by the ministry, the development of quiet pavement alternatives can provide a more cost-effective solution to address noise pollution in urban areas than use of noise barriers. The studies have shown that pavements with different textures provide different noise reduction effects and open graded asphalt mixes and longitudinally grooved concrete pavements have shown the best long-term performance in sound mitigation. This paper presents the findings from the above noted pavement noise studies conducted by MTO between 2009 and 2022. Longitudinal grooved concrete pavement and open graded asphalt pavement textures are found to provide the best tire-pavement noise mitigation at the source for the flexible and rigid pavement, respectively. It is recommended to upgrade the traffic noise model (TNM) developed by Federal Highway Administration (FHWA) that MTO is currently using to account for new pavement textures, which is essential for accurate environmental screening of road projects.

Microscopic Analysis of Work Zone Delay using Big Data and Logistic Regression

Tue, 11/21/2023 - 15:45
Microscopic Analysis of Work Zone Delay using Big Data and Logistic Regression
by Morshedzadeh,Y; Gargoum,S.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5121 - INTERNET


Work zone traffic management poses a significant challenge due to the need to minimize traffic delays while maintaining a safe environment for workers. In order to effectively manage traffic through work zones, it is necessary to understand how delays are affected by both internal and external factors, such as the work zone's design characteristics, road geometry, weather conditions, and traffic conditions. Despite the literature's attention to modeling work zone delays, most studies are limited to analyzing data from a small number of work zones and consider limited travel time observations. Macroscopic travel time prediction is also a key focus of existing literature. To address those gaps and provide a better understanding of factors affecting delay in work zones, this study uses a big dataset consisting of 15 million travel time observations collected every 2-3 minutes at 624 work zones located between the western borders of Alberta and Vancouver, BC. A microscopic delay analysis was performed whereby the impact of spatial, temporal, environmental, and segment-related variables on work zone delays was assessed using ordinal logistic regression. Based on the model statistics, high delays were associated with hourly traffic volume, peak hours, weekend travel, length of the work zone, and summertime, whereas precipitation affected delays in the opposite direction.

Longitudinal Joint Specification, Construction, and Performance for Flexible Pavements in Canada

Mon, 11/20/2023 - 20:44
Longitudinal Joint Specification, Construction, and Performance for Flexible Pavements in Canada
by Agbedor,A; Sanchez,X.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5120 - INTERNET


Longitudinal joints are the long seams between paving lanes made by subsequent passes of the paver to cover the surface being paved. Longitudinal joints are often the weakest area of asphalt pavements and are susceptible to early deterioration. Deterioration starts when air, water, and contaminants find their way into the joint through areas of segregation, poor density, or inadequate bond between the two mats forming the joint. Addressing this weakness will greatly delay maintenance and increase overall pavement life. One option to prevent longitudinal joint deterioration is to eliminate the joints altogether through echelon paving, which involves paving multiple lanes side-by-side at the same time with multiple pavers. Unfortunately, on most paving projects, the paving width is limited, and there is a need to maintain an acceptable level of traffic flow that prevents multi-lane paving. Consequently, most paving projects must be paved one lane at a time, which requires the construction of conventional joints. Several techniques exist for the construction of longitudinal joints, and in Canada, user agencies are exploring innovations in materials, construction methods, and specifications for improving longitudinal joint performance. As a start, a survey was conducted of Canadian agencies to gain insight into the current specifications and practices utilized in Canada in the construction of longitudinal joints. This paper discusses the results of the survey and the specifications and practices agencies reported to be acceptable and highly effective based on field performance. The paper also discusses a literature review on research of materials such as joint sealers or void-reducing asphalt membranes and construction practices that result in lower air void contents (higher densities) at the longitudinal joints and better performance.

Large Culvert Renewal in New Brunswick

Mon, 11/20/2023 - 20:17
Large Culvert Renewal in New Brunswick
by Northmore,A; Burke,S; MacDonald,G.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5119 - INTERNET


The New Brunswick Department of Transportation and Infrastructure (NBDTI) faces numerous challenges in maintaining and renewing their aging culvert infrastructure. While bridge-sized culverts (3000 mm diameter and larger) have historically been given significant focus, an effort to better manage Large Culverts (over 1200 mm to under 3000 mm diameter) only began in 2008. Despite this effort, managing the Large Culvert infrastructure has continued to prove challenging, so NBDTI in conjunction with Englobe Corp. reviewed NBDTI’s existing culvert infrastructure and management practices, on the entire process from inspection, project conception, pre-design, design, rehabilitation, and construction. This research culminated in a report summarizing the state of NBDTI’s Large Culvert management with a set of recommendations for developing an improved approach to Large Culvert Renewal in New Brunswick. Further work was completed in Phase 2 of the study focusing on several of the opportunity areas identified through the Phase 1 research and consultations, as well as discussions with the NBDTI steering committee. One of the main foci for this part of the research was to estimate the ongoing budgetary needs to manage the backlog of large culvert renewals in the medium-term and to make the program sustainable in the long-term. This task required estimating the condition of the existing inventory and estimating the replacement value of each large culvert. Other focus areas included developing a maintenance plan, renewal options decision tree, and guidance around district training, renewal of large culverts under large fills, and developing a definition of emergency as it pertains to large culvert replacement.

Jurisdictional Scan of Sidewalk Management Practices from North American Municipalities

Mon, 11/20/2023 - 19:43
Jurisdictional Scan of Sidewalk Management Practices from North American Municipalities
by Zhao,G; Ahmed,R; Whiteley-Lagace,L; Surette,E.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5118 - INTERNET


Sidewalks generally receive lower attention than primary infrastructure, such as roadways and bridges. Lawsuits incurred from sidewalk hazards can be costly for jurisdictions and detrimental to public perception of safety and mobility. Many municipalities recognize the importance of maintaining sidewalk assets systematically, from condition evaluation to treatment selection. However, limited resources for sidewalk assets, such as standards, reports, and research papers, are available. To gain a better understanding of sidewalk management practices, a survey was distributed to select municipalities across North America. The survey comprised 41 questions covering various sidewalk management aspects, including sidewalk network information, data collection methods, distress types, data quality check and calibration, and management system. Analyses were performed on the collected survey feedback. The results show that, while some respondents have similar sidewalk network sizes to maintain, the available budget varies greatly. Most participating municipalities do not have calibration and/or acceptance criteria for the collected sidewalk condition data. Subsequently, a condition rating system and/or performance index have not been developed for sidewalks. This may lead to unspecified treatment triggers and inconsistent decision-making processes. The data and findings presented in this paper can serve as a reference for any size municipality looking to benchmark its sidewalk management practices.

Heating Longitudinal Joints with Infrared Heaters to Improve Performance The City of Calgary’s Joint Density Specification

Mon, 11/20/2023 - 19:24
Heating Longitudinal Joints with Infrared Heaters to Improve Performance The City of Calgary’s Joint Density Specification
by Mulk,N; Ghimire,D; Aurilio,V.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5117 - INTERNET


Premature longitudinal joint failures due to low density, water intrusion, cracking, and ravelling is a common and significant issue in asphalt roadways. Joints often fail first despite the rest of the mat being constructed properly with suitable mixes. Premature joint deterioration reduces the pavement's life cycle and requires increased maintenance, wastes time, budget, environmental and safety concerns due to traffic accommodation. In 2021 and 2022, the city conducted pilot studies using infrared heaters during paving to create heated joints. The city is continuing its study through 2023. To facilitate implementation of the joint density specification and to evaluate the overall effectiveness, the contractor was required to heat the construction joint using an infrared joint heater supplied by Heat Design Equipment in 2021. Preliminary results were encouraging with improved densities and reduction in air voids. As such, the City decided to proceed with the joint density specification on contracts in 2022/2023. This paper presents the preliminary results of the longitudinal heated joints from the City's 3-year study, including the development of specifications, best construction practices, challenges, and maintenance. The city plans to continue heating joints, particularly on high-volume roadways and multi-lane pavements, and further improve the current specifications.

Examining Perceptions of Autonomous Transit from the Perspective of Multi-Use Path Users

Mon, 11/20/2023 - 19:04
Examining Perceptions of Autonomous Transit from the Perspective of Multi-Use Path Users
by Svendsen,D; Fatmi.M.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5116 - INTERNET


The emerging technology of autonomous vehicles has a multitude of ways in which it can drastically affect urban transportation. Given its improving ability of precise operation, one such way is the potential for driverless public transport to be implemented along narrow corridors with other road users. The purpose of this study is to investigate the perception of autonomous transportation for those who currently use one such corridor, the Okanagan Rail Trail (ORT) in Kelowna, British Columbia. This corridor runs through the heart of the city connecting major destinations such as Downtown Kelowna, a university, and an international airport. The idea is to offer transit services along a dedicated corridor, which could further increase the usage of this corridor, offer modal transfer, and increase safety by offering passive surveillance for the trail users. Given the space constraint, Autonomous Transit (AT) is considered to be a fitting technology for this application. However, the facility does not currently allow any heavy vehicles and is used by active transport users such as pedestrians, cyclists, e-scooter riders, among others. Hence, it is of critical importance to understand the existing users’ perception towards this new transport mode. In order to analyze this impact, an intercept survey was developed to gather information regarding users’ perspectives on AT along the ORT, their current rail trail usage, and their socio-demographic characteristics. 737 trail users were surveyed, and after data cleaning, 718 responses were found to be sufficiently complete for analysis. The data shows that 52% of trail users agree with a form of AT along the ORT, though 47% of those surveyed indicated they were not fully comfortable with the technology. A strong majority of 83% of surveyed respondents indicated that the transit vehicles should only operate within their own dedicated right-of-way. 34% of respondents indicated that this would reduce the use of their private vehicles, though this varied quite significantly through the different age categories, with 46% of those between 25 and 34 agreeing with the sentiment compared to only 25% of those between the ages of 65 to 74. The results shed light on the factors (such as trust and acceptance of emerging technologies, socio-demographics, and travel patterns) affecting the perception towards the implementation of a disruptive technology alongside vulnerable road users such as pedestrians and cyclists.

Effect of Subgrade, Subbase and Base Materials on the PMED Software Predicted Distresses in Jointed Plain Concrete Pavement

Mon, 11/20/2023 - 18:46
Effect of Subgrade, Subbase and Base Materials on the PMED Software Predicted Distresses in Jointed Plain Concrete Pavement
by Ahammad,MA; Smith,TJ; Podborochynski,D; Saha,J; Dhaliwal,A; Roby,J.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5115 - INTERNET


Between May 2022 and August 2022, the Transportation Association of Canada (TAC) Mechanistic Empirical (ME) Pavement Design Subcommittee has completed a number of design trials to assess the effect on the AASHTOWare Pavement ME Design (PMED) software predicted distresses in jointed plain concrete pavement (JPCP) due to varying subgrade and subbase and base materials. These trials were run with climatic inputs from nine different climate stations across Canada, five different untreated native subgrade soils/fill, five different soil cement layers, a crushed rock subgrade, six different base (cement treated and granular) materials with varying thickness and two different granular subbase materials. The results have shown that climate has a significant effect on the predicted IRI and faulting. No design meets the IRI criteria for clay and silt subgrade soils in cold climates. When a crushed rock layer is used as a subgrade, all designs meet the IRI criteria and the effect of underlying native subgrade soils becomes minimal. With native subgrade/fill alone, the predicted IRI decreases as the material physical properties improves. The physical properties of subgrade soils have more influence on the predicted IRI than their stiffness. Inconsistent and unexplainable trends of the predicted faulting at concrete joints were observed for changes in subgrade type. There was no or negligible effect on the predicted transverse cracking due to changes in subgrade material type and variation in climatic exposure. Currently, PMED software is unable to model the stabilized soils as subgrade. In general, good quality and thicker base layers provide lower IRI and faulting with some inconsistencies. The variations of the predicted transverse cracking for changes in base material type and thickness were inconsistent. Poor quality subbase materials cause a small increase while thicker subbase layers cause an inconsistent variation of the predicted distresses. Significant differences in predicted distresses, with many inconsistencies in the trends, were noted between the PMED software v2.6 and v3.0.

Effect of Portland Cement Concrete Mix Properties, Thickness, Joint Layout and Traffic Loading on the PMED Software Predicted Distresses in Jointed Plain Concrete Pavement

Mon, 11/20/2023 - 16:37
Effect of Portland Cement Concrete Mix Properties, Thickness, Joint Layout and Traffic Loading on the PMED Software Predicted Distresses in Jointed Plain Concrete Pavement
by Ahammed,MA; Smith,TJ; Leung,YTF; Esfandiarpour,S; Khanal,S; Roby,J; Ghazy,A.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5114 - INTERNET


Between September 2022 and March 2023, Transportation Association of Canada (TAC) Mechanistic Empirical (ME) Pavement Design Subcommittee completed five sets of design trials using the AASHTOWare Pavement ME Design (PMED) software to assess the effects of portland cement concrete (PCC) mix properties, coefficient of thermal expansion (CTE), slab thickness, dowel diameter, joint spacing and traffic loading on the predicted distresses in jointed plain concrete pavement (JPCP). The trial results using software v2.6 indicated that a better quality concrete results in improved performance in terms of predicted international roughness index (IRI), faulting and cracking. Only a high CTE of >8.0x10-6/ºC seems to affect the predicted transverse cracking. Varying climate was shown to have significant effect on the predicted IRI, a lesser effect on the predicted faulting and no or negligible effect on the predicted transverse cracking. The trial results also showed some inconsistencies and significant differences in the predicted distresses between software v2.6 and v3.0. The trial results using software v3.0 showed that an increase in the PCC thickness results in an increase in the predicted IRI and faulting, which is not expected. An increase in the PCC thickness showed a reduction in the predicted transverse cracking. The trial results also showed that thicker dowels provide a significant reduction in the predicted faulting and IRI, but have no or minimal effect on the predicted transverse cracking. PCC joint spacing showed no or minimal effect on the predicted IRI, a significant effect on the predicted joint faulting for PCC layer thicker than 200 mm and for high CTE values and a significant effect on the predicted transverse cracking. Traffic loading has a small effect on the predicted IRI. The minimum PCC thickness should be 205 mm and CTE should be 8.0x10-6/ºC to produce an impact of traffic loading on the predicted faulting. Transverse cracking is highly sensitive to traffic loading with thinner concrete. Overall, a high CTE value has shown a greater impact on the predicted performance than joint spacing and PCC thickness, which seems to be unreasonable and requires further investigation.

Effect of GU vs. GUL Cement on AAR Testing of Concrete Aggregates

Wed, 11/15/2023 - 21:26
Effect of GU vs. GUL Cement on AAR Testing of Concrete Aggregates
by Jiang,Z; Verros,A; Shehata,M.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A55113 - INTERNET


Alkali-Aggregate Reaction (AAR) is a severe deterioration affecting concrete infrastructures worldwide. AAR occurs when the aggregates react with the alkalis in cement used for the concrete, thereby producing pressure within the concrete that causes expansion, deterioration and cracking. The Ministry of Transportation (MTO) evaluates the reactivity of concrete aggregates using the MTO laboratory methods, Accelerated Mortar Bar Test (LS-620) and Concrete Prism Test (LS-635), demanding the use of Portland Cement (GU). The introduction of Portland-limestone (GUL) cement calls for an investigation of the aggregate reactivity with GUL cement using the two test methods. The findings would support the ministry’s understanding of the difference in expansion with the use of GU and GUL cements and any impact of using GUL cement on the two test methods. This paper reports on the LS-620 test data on four MTO reference aggregates (two quarried siliceous limestones (ASR CA3 and CA6) from Ottawa area, a quarried dolomitic limestone (ACR CA1) from Kingston area, and a crushed siliceous gravel (ASR CA5) from Sudbury area) using both GU and GUL cements from cement suppliers in Canada. The data were produced through MTO Aggregate and Soil Proficiency Program and MTO-Toronto Metropolitan University partnering program. Multi-stage statistical methods were used to analyze the data.

Development of Climate Adaptation and Asphalt Selection Tool (CAAST)

Wed, 11/15/2023 - 20:37
Development of Climate Adaptation and Asphalt Selection Tool (CAAST)
by Maadani,O; Shafiee,M; Hiedra-Cobo,J.
2023.
Transportation Association of Canada 2023 Conference and Exhibition - Lessons in Leadership // Association des transports du Canada 2022 Congrès et Exposition - Lecons de Leadership.
CA6 ARH_10 2023A5112 - INTERNET


This paper introduces the Climate Adaptation and Asphalt Selection Tool (CAAST), which is a new computer software used to select climate resilient Performance Grade (PG) of asphalt binder for Superior Performing Asphalt Pavements (Superpave) based on extreme high and low pavement temperatures. Developed by National Research Council Canada (NRC), CAAST uses projected climate change temperature data provided by Environment and Climate Change Canada (ECCC) for Canadian cities, obtained from the Canadian Regional Climate Model (CanRCM), version 4, from 1950 to 2100. The CAAST software analyzes the projected temperature data file within a certain time period (i.e.: road design life) to extract and calculate environmental parameters that will be used to assess the impact of climate change and to select the climate resilient asphalt binder performance grade (PG). CAAST incorporated the shortcomings of the existing Long-Term Pavement Performance Bind Online (LTPPBind) such as standing traffic speed, besides slow and fast traffic speed and annual temperature variations in terms of Degree Days (change within a year not only during 6 months). The paper compares and analyzes Superpave PG results obtained from ECCC's projected temperature data via CAAST against the existing method (LTPPBind) based on Modern-Era Retrospective Analysis for Research and Applications (MERRA-2) temperature data. The study shows that the indices such as Mean Annual Lowest Air Temperature (MALAT) and Mean Annual Degree Days (MADD) for cities in Atlantic, Central, Prairies, Western and Northern Canada are significantly higher when using the new proposed method compared to MERRA-2. The analysis also suggests that climate change can induce higher upgrades in high and low PG grades over the next 25 years than those predicted by MERRA-2 via LTPPBind. Consequently, the use of CAAST with embedded projected air temperature data can provide an effective solution for selecting resilient PG binder types in response to climate change, which is an improvement over traditional approaches that rely on historical climate. Overall, this study highlights the importance of considering climate change projections in pavement design and emphasizes the need for tools like CAAST to ensure pavement performance under changing environmental conditions.

The Big Lift: Redecking the Macdonald Bridge

Tue, 10/17/2023 - 18:50
The Big Lift: Redecking the Macdonald Bridge
by Wilson,D.
2017.
CA3NV HD____ 2017B34 - MAIN


The Big Lift is an intriguing book that melds a blend of environmental portraits, industrial grime and Dale Wilson’s acute awareness of natural light. Wilson showcases 91 photographs from his collection of thousands made while on assignment with Halifax Harbour Bridges. The snippets of informative text will introduce the reader to interesting facts and light-hearted anecdotes. It will be a lasting legacy documenting only the second time in the world the suspended span of a suspension bridge has been replaced at night and open during the day. The first was on the Lion’s Gate Bridge in Vancouver.

Staged Road Construction in Very Weak Subgrade Using Polymeric Geocell

Wed, 10/04/2023 - 20:45
Staged Road Construction in Very Weak Subgrade Using Polymeric Geocell
by Chatterjee,AK; Poharel,SK; Breault,M.
2022.
Transportation Association of Canada 2022 Conference and Exhibition - Changing Ways for our Changing Climate // Association des transports du Canada 2022 Congrès et Exposition - Approches Adaptées pour un Climat changeant.
CA6 ARH_10 2022A5129 - INTERNET


The ongoing development of the energy industry in Canada, especially for pipeline-related structures, demands innovative ways of access construction. Most of these are at remote locations and under difficult geotechnical conditions making access a challenge. A 4.1km long unpaved access road leading to a proposed compressor station in Blainville, Quebec was planned for the construction of the station pad and future access. The road was expected to serve as a material haul road for the 200m x 250m gravel pad, regular compressor station construction loads, and future traffic. Construction of the pad was scheduled to start before the winter of 2020. The proposed road alignment had very soft to soft subgrade conditions with saturated peat. There were problems with limited right of way, a landslide-prone zone, a creek crossing, and overhead powerlines. The road geometry was to be designed such that there was enough clearance from the overhead powerlines and the slide-prone area and maintain the minimum turning radius required for the long and heavy trucks carrying compressor units. Additionally, there were constraints imposed in permits and other aspects of the project that left a short 6-week window for the construction of the road. The existing subgrade was high water-bearing peat with depth varying from 0.6m to 2m. Removal of the peat and bringing engineered fill was not practical from cost, schedule, and environmental permit perspectives. A non-conventional design on top of a weak subgrade with geocell was deemed necessary. The limited construction schedule did not allow for building the minimum reinforced structure necessary to support design loads, particularly the 65 Metric Ton compressor load. As an engineered solution, a road was initially designed for the design load limits and a maintenance plan for the operation. Taking advantage of the high-strength novel polymeric alloy (NPA) geocell load support mechanism, it was possible to avoid any material removal and yet build a minimum structure for initial construction traffic including some heavy haul traffic. Strict load restrictions were imposed on the temporary bridge. The initial design was done in a way to accommodate the final construction with minimum adjustments and without hindering continuous access to the pad. For low power lines and right of way, fill limits on the final design were further reduced with an additional layer of geocell. This paper describes in detail the design methodology and maintenance program that was implemented through the construction phases.

Synthesis of Emerging Practice: Continuous Sidewalks and Bike Paths

Tue, 06/13/2023 - 17:42
Synthesis of Emerging Practice: Continuous Sidewalks and Bike Paths
by Symons,R; Pinder,M; Gould,B; Pekar,N; Gong,W; Woodhall,T; Pareek,S; Greco,L; Fipke,A; Esarte,A; Boeske,M; Nickerson,P; Storer,P; Darwent,C.
20.
CA6 ARH127 2023C57 - INTERNET


Continuous sidewalks and bike paths are best known from their use in the Netherlands. Their purpose is to prioritize people on foot and bicycle over turning motor vehicles at crossings of local streets. Priority is inherent to the design of the intersection, and the continuity of the sidewalk and bike path treatment clearly conveys that vehicles are crossing the pedestrian and bicycle realm. This is unlike a typical North American local street intersection, where pedestrians are required to cross the roadway or vehicle realm. The first known application of this technique in Canada was by the Town of Canmore in 2016. The City of Vancouver implemented a few in 2018, and in 2020, the City of Nanaimo took the concept further, identifying continuous sidewalks and bike paths as a standard for local street intersections, building several on Metral Drive, the first corridor to apply the standard. An important distinction with respect to this emerging practice is that the key design features included in continuous sidewalks and bike paths have already been used in the context of residential and commercial driveway crossings and laneways for many years. This document focuses specifically on the use of continuous sidewalks and bike paths on municipal streets. This document provides examples of continuous sidewalks and bike paths, as well as existing guidance that could be relevant to their design. However, there are many examples that span a wide range of contexts and use a wide range of design dimensions for various elements. This document provides information for consideration by the reader but does not constitute design guidance, and should not be used as such.

Traffic Data Collectors in Arctic and Remote Conditions

Mon, 05/29/2023 - 15:08
Traffic Data Collectors in Arctic and Remote Conditions
Government of the Northwest Territories Department of Infrastructure.
2023.
CA6 ARH350 2023T62 - INTERNET


In 2020 the Government of Northwest Territories (GNWT) deployed a traffic data collection system which spanned our entire road network, including artic locations. The solution provider for the project was Stinson ITS, and they were great to collaborate with. These sensor systems were connected to the internet via both LTE cellular and satellite communications, in order to continuously collect data as well as monitor the heath of the devices. In the cloud-based web interface we can access our data via a range of built-in reporting tools as well as download it in raw format. This project was an exciting one for us, our previous data collection system had experienced extensive reliability and maintenance issues. It was a loop based system and was not connected to the internet. Our climate, which often reaches -50C in winter, did not work well with the loops and when these systems failed we wouldn’t know because there was no connectivity. This resulted in very large gaps in our data which interfered with our planning processes. As such we were very excited to deploy a modern and reliable system.

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