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Culvert Inspection to Asset Management: Climate-Change Informed Capital Works Program for Alaska Highway

Mon, 12/04/2023 - 19:49
Culvert Inspection to Asset Management: Climate-Change Informed Capital Works Program for Alaska Highway
by Waseem,A; Daly,S; St Michel,G; Taheri,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 2023A5146 - INTERNET


The paper outlines a comprehensive approach utilizing culvert inventory and condition data collected based on the AASHTO Culvert and Storm Drain System Inspection Guide (2020) to develop a condition, and climate-informed risk-based twenty-year capital works program for 2,200 culverts on Alaska Highway. The paper goes on to explain the methodology for establishing monetized life-cycle failure risks stemming from condition deterioration and extreme climate events. The life-cycle risk assessment is used to develop a culvert asset management system, which is used to produce a multi-year climate-informed capital works program. In a previous study, a climate change vulnerability and risk assessment were completed on selected critical culverts on the highway using inventory and limited condition data collected 10 years earlier. As an outcome of this previous study, a comprehensive culvert inspection was carried out in 2022 based on the more robust data collection criteria outlined in the Culvert and Storm Drain System Inspection Manual (AASHTO, 2020). This 2020 AASHTO Inspection Manual, updates the inspection and rating criteria, incorporating over 30 years of changes since its original publication in 1986. The previous study's approach to assessing the risks posed by condition deterioration and climate change to 2,200 culverts along the Alaska Highway, British Columbia, was improved with more accurate culvert components-based predictive models to develop a capital works program to address those risks in terms of replacement, adaptation, and maintenance. The adaptation and/or replacement options, (strategies), were evaluated in a Life Cycle Cost Analysis (LCCA), by monetizing the costs and benefits of multiple strategies over a 60-year period. The economic analysis for climate change adaptation options quantifies the extent of cost and benefit of adaptation options under climate change scenarios. The costs considered in the LCCA include both "direct costs," directly incurred by the asset owners, and "user costs," which road users would incur through delays and detours. Overall, this approach should ensure that the culverts along the Alaska Highway can withstand the impacts of climate change and remain functional over the next 20 years.

Who uses shared mobility services?

Thu, 11/23/2023 - 19:33
Who uses shared mobility services?
by Hewage,U; Davanzo,E; 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 2023A5146 - INTERNET


Shared mobility services such as bike sharing, scooter sharing, car sharing, and ride-hailing can act as a catalyst to improve the quality of urban transportation services. This includes making them more accessible, sustainable, and equitable. With proper regulations and planning, shared mobility can enable cost savings, provide convenience, and reduce vehicle ownership. For this to happen, cities need to understand the users’ behaviour – e.g., what factors are affecting this choice of travel mode. This study focuses on investigating the willingness to use shared mobility services and evaluating the associated socio-demographic characteristics of users. Data comes from a survey conducted in Kelowna, British Columbia, which collected information regarding the usage of a wide array of shared mobility services, travel behaviour and attitude towards shared mobility, driving, land use, among others. Exploratory factor analysis results show that there are 11 attitudinal factors representing individuals’ travel characteristics. The multivariate probit model results suggest that based on the correlation coefficient values, there is a positive significant relationship with shared e-bike and shared e-scoter usage and shared e-bike and car share usage. It also suggests that there is a negative significant relationship between public transit usage and ride-hailing usage. Substitution effects confirmed by the model are that public transit usage is associated with shared e-scooter, car share, and ride-hailing modes and shared e-bike usage is associated with public transit usage. The results of the study can be utilized by cities and transit agencies to improve the availability of shared mobility services to enable efficient usage of sustainable travel modes in our day-to-day lives.

Using Sensing Technology for Pavement Performance Monitoring in Edmonton, Alberta

Thu, 11/23/2023 - 19:10
Using Sensing Technology for Pavement Performance Monitoring in Edmonton, Alberta
by De Carvalho Linares,SHB.
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 2023A5145 - INTERNET


Pavements in cold regions are continuously under the influence of extreme climates, in addition to variable and ever-increasing traffic loads. Consequently, various types of structural failures can occur depending on specific circumstances and construction features. Thus, a well-planned pavement maintenance strategy must take place throughout the years to reach the designed service life and even sustainably extend the pavement structure's lifetime. An accepted and widely practiced process for continuous monitoring of the pavement conditions is collecting environmental and performance data using sensors installed in different pavement structural layers. In fact, the embedded instrumentation in the pavements can be an effective tool for capturing data such as temperature, moisture, and the induced stresses and strains within the pavement structure, allowing professionals in the field to determine the appropriate maintenance approach based on the collected information. This paper is divided into two main parts. The first part aims to provide a literature review on the sensors used for the instrumentation of pavements. Based on the review of different case studies, this study shows various applications of pavement sensors and their significance for analyzing pavement conditions. The second part of this study focuses on the instrumentation of a test section which was constructed in July 2022 in Edmonton, Alberta. This part mainly discusses the construction and instrumentation of the smart road test section and the application of artificial intelligence to predict the pavement performance based on the captured data.

Ultra-High Performance Fibre Reinforced Concrete (UHPFRC) Applications and Best Practices

Thu, 11/23/2023 - 18:50
Ultra-High Performance Fibre Reinforced Concrete (UHPFRC) Applications and Best Practices
by Aqel,M; Titherington,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 2023A5144 - INTERNET


Since the development of ultra-high performance fibre reinforced concrete (UHPFRC) in the late 1990s, the use of this type of concrete has grown significantly. This is due to the superior mechanical and durability characteristics of UHPFRC compared to regular concrete. The Ontario Ministry of Transportation (MTO) utilizes UHPFRC in field-cast joint applications between precast concrete bridge deck panels. MTO has recognized the benefits that could be achieved with the use of UHPFRC including the superior flexural strength that ensures continuity of the precast panels and the good long-term performance due to the extremely low porosity and superior toughness. MTO’s first use of UHPFRC was in 2006, for field cast joints. MTO has tendered the use of UHPFRC in this application for over 120 structures. Every year, nine to fifteen bridges are constructed with UHPFRC field-cast joints. The majority of bridges where UHPFRC has been used by MTO are located in the province’s Northeast and Northwest Regions, where primarily precast concrete is used for bridge construction. Currently, for a UHPFRC product to be used in MTO work, the product must pass the designated sources of materials (DSM) approval criteria and be listed on DSM list 9.25.50. This paper aims to present MTO’s experience with UHPFRC used in field-cast joints. This includes the best practices for material handling and storage, mixing, placing, finishing, curing and surface preparation. The advantages and limitations of the UHPFRC will also be presented based on MTO’s experience. Furthermore, the paper will present the steps that MTO has taken through the pre-approval acceptance criteria, specifications and quality assurance testing to ensure the successful use of UHPFRC in field-cast joints.

Transformation of an Arterial Highway Bridge to an Operational Bridge Weigh in Motion

Thu, 11/23/2023 - 18:30
Transformation of an Arterial Highway Bridge to an Operational Bridge Weigh in Motion
by MacLeod,E; Bowmaster,J; Arjomandi,K; MacDonald,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 2023A5143 - INTERNET


As highway infrastructure ages and degrades, the ratio of traffic demand to capacity is increasing, making oversized and overweight vehicles a common concern worldwide. Overweight vehicles can cause significant damage to bridge structures, accelerate degradation, shorten the service life, and ultimately lead to a collapse in some instances. This has resulted in a growing interest in the development of technologies and systems that can monitor the frequency and characteristics of overweight loading events and the effect they have on bridge structures. Bridge Weigh in Motion (BWIM) systems use the deformation of a bridge, under live loading, to estimate the characteristics of passing traffic loads. An existing bridge is instrumented with a series of sensors that use the full bridge as a weighing mechanism. The implementation of such a system is discussed through a full-scale case study arterial highway bridge in the province of New Brunswick, Canada. The value of BWIM is examined, operational data is presented, and key findings are discussed.

Toward Performance-Based Acceptance of Asphalt Mixtures in Ontario: Industry (O-MAP) Preliminary Findings

Thu, 11/23/2023 - 17:59
Toward Performance-Based Acceptance of Asphalt Mixtures in Ontario: Industry (O-MAP) Preliminary Findings
by Ambaiowei,DC; Varamini,S; Aurilio,M; Alamdary,YA.
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 2023A5142 - INTERNET


Research efforts are being undertaken in North America, to improve methodology for designing asphalt mixes through incorporating reliable laboratory tests and procedures into material specifications. Some of these efforts have further demonstrated that implementing performance tests can improve the longevity of asphalt pavements and reduce risk of premature pavement deterioration. The Ontario Asphalt Pavement Council (OAPC – A Council of Ontario Road Builders’ Association, ORBA) is particularly interested in this focus, as potential means of addressing concerns on premature cracking of asphalt mixes. Considering this, the Ontario Asphalt Expert Task Group (OAETG) – Ontario - Mix Asphalt Program (O-MAP) study, commissioned by the OAPC, has been conducted to examine issues and challenges related to the performance of typical Ontario Superpave asphalt mixtures. Further to the industry’s readiness to identify any issues and challenges involving performance of typical Ontario Superpave asphalt mixtures, this paper summarises the findings, recommendations, and next steps from round-one of O-MAP Testing. Throughout this round, two SP 12.5 mixes designed specifically for highest Traffic Category (“E”) were studied. The evaluated mixes were Plant-Produced Lab Compacted (PP-LC) prepared using Performance Graded Asphalt Cement (PGAC) 70-28XJ, meeting Ontario Provincial Standard Specification (OPSS) 1101. The results indicated that the success of adopting performance testing in Ontario is reliant on the ability of both the owner-agency and industry to establish and meet performance criteria related to test methods including, but not limited to: Hamburg Wheel Tracking Device (HWTD), Semi-circular Bend Test (SCB), and Disk-Shaped Compact Tension (DCT) array of tests. The round-one results were further incorporated into Performance Space Diagram (PSD) to better characterize the mixes based on performance testing conducted. Based on the identified study limitations and results analyzed and verified by the O-MAP’s Oversight Study Team (OST), there are still areas requiring further investigation in order to better understand the factors that may affect the interpretation of results. To this end, different mix properties, testing parameters, testing equipment/fixtures, or a combination of all these factors, including the effect of changing height on the reliability of Superpave Gyratory Compactors (SGCs) used in the province, and their differences as a significant source of variation related to "within" and/or "interlaboratory" Coefficient of Variation (COV) should be further investigated.

The Minimum Thickness of Asphalt Concrete Layer for the Design of Flexible Pavement on Low Volume Roads Using the PMED Software

Thu, 11/23/2023 - 16:28
The Minimum Thickness of Asphalt Concrete Layer for the Design of Flexible Pavement on Low Volume Roads Using the PMED Software
by Ahammed,MA; Saha,J; Podborochynski,D; Leung,YTF; Esfandiarpour,S; Dhaliwal,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 2023A55141 - INTERNET


A large portion of Canada’s highway network is low traffic volume roads with thin pavement structures. Currently, no generally accepted design method is available for these roads. As such, pavement design and/or construction methods vary widely among the jurisdictions. The AASHTO 1993 guide recommends the same design approach for thin asphalt (<100 mm asphalt) pavements as the conventional flexible pavements, but with a lower level of reliability. These design outcomes are cost prohibitive in most cases considering traffic uses. This paper examined the suitability of the AASHTOWare Pavement ME Design (PMED) software for the design of thin asphalt pavements. In 2022, the Transportation Association of Canada (TAC) Mechanistic-Empirical (ME) Pavement Design Subcommittee completed extensive design trials for thin asphalt concrete (AC) pavements using the PMED software. These design trials used varying climate data across Canada, subgrade soil types, base/subbase thickness combinations, and asphalt concrete (AC) thicknesses that ranged 50 mm to 150 mm. The trial results have shown uniform trends of the predicted total rutting when the AC layer thicknesses were =60-80 mm, depending on the subgrade stiffness. Uniform trends for the predicted bottom-up fatigue cracking were observed when the AC thicknesses were =100-105 mm. The predicted AC layer rutting were inconsistent among the design variables. There was no noticeable effect of varying AC layer thickness on the predicted top-down fatigue cracking. Very good correlations (with R2 values >0.98) were observed between the AC layer thickness and the predicted IRI as well as between the AC layer thickness and the predicted total rutting. Overall, these trial results indicated that PMED software can be used to design pavements with a minimum AC thickness of approximately 100 mm (4 in.) considering all type of distresses. However, considering only the IRI and total rutting criteria and ignoring small irregularities in the trends of predicted IRI and total rutting in pavement designs for low traffic volume roads, an AC thickness of as low as 50 mm could be used when using the PMED software.

The Impact of Polyethylene Terephthalate (PET) Fibres on the Cracking Resistance of High-Performance Asphalt Concrete (HPAC)

Wed, 11/22/2023 - 20:30
The Impact of Polyethylene Terephthalate (PET) Fibres on the Cracking Resistance of High-Performance Asphalt Concrete (HPAC)
by Ahmed,N; Saleh,M; Moghaddam,TB; Hashemian,L.
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 2023A5140 - INTERNET


The safety of a road network highly influences its overall productivity and efficiency. High-performance asphalt concrete (HPAC) is an innovative paving mixture in the design and construction of high-traffic roads in North America, which has high strength, good fatigue life, and excellent rutting resistance. However, the HPAC application is limited in colder regions because of the material's low flexibility and stress relaxation capacity. A road pavement undergoes different types of defects and failures throughout its design life, and cracking is one of them. Cracking in the asphalt pavement is introduced by numerous causes, such as heavy traffic, low temperature, and poor drainage. Cracking in the asphalt pavement negatively affects a road's lifespan and increases the maintenance cost of a road. Therefore, the objectives of this study are to evaluate the impact of asphalt mix modification in terms of resistance to cracking and improvement of cracking tolerance in high-performance asphalt concrete with the utilization of Polyethylene Terephthalate (PET) fibres in the mixes. Three different lengths of PET fibres (6 mm, 12 mm, and 18 mm) are used in the mixes. A binder source-H with PG 70-22 is used for fabricating the HPAC throughout this research, which is modified with 12% asphaltenes (by the weight of binder). An indirect tensile cracking test (IDEAL-CT) at an intermediate temperature of 25 and at 37 according to the PG grading of the binder as per ASTM D8225 for all the asphalt mixes is carried out to determine the cracking tolerance (CT) index values, failure energy, and indirect tensile strength. The analysis of the test results shows that the failure energy and the indirect tensile strength properties of the asphalt mixes are improved with the addition of PET fibres in comparison with the control mixes at 25 . However, it is observed that increasing the fibre length improves the CTindex, failure energy, and indirect tensile strength when the specimens are tested at the temperature of 37 .

The effect of truck loading factor on a major trucking route in Québec and on GHG emissions

Wed, 11/22/2023 - 19:53
The effect of truck loading factor on a major trucking route in Québec and on GHG emissions
by Tadja,HD; Begin-Drolet,A; Lepine,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 2023A5139 - INTERNET


In this paper, we hypothesized that it is possible to reduce trucking greenhouse gas emissions in a relatively short time horizon by improving efficiency. As a matter of fact, improving truck efficiency by increasing their loading factor, in other words, maximizing the time when trucks are fully loaded and minimizing when they run without a cargo is a low hanging fruit that could be enforced by local incentives or regulations for long-haul cargo. This study analyzes the effect of truck loading factor on a major trucking route in Québec (highway 20) and it estimates potential GHG emission economy with a linear regression for different average load-factor scenarios. The regression analysis shows that removing 20% of the empty trucks travelling in the province of Quebec could lead to an annual reduction of 1.2 million tons of CO2 and social savings of nearly 300 million $. Results are based on a Monte Carlo analysis made with a tool called the MapEUR which uses different databases on trucks registrations, operation, road characteristics and weather conditions to estimate the fuel consumption of all the trucks travelling of a specific road segment and a given period. The scenario comparison provides better understanding of the potential benefits of increasing load factors and guide the amount of efforts that should be given from fleet operators and policy makers toward such solutions.

The effect of antifreeze additives on concrete performance with and without nano-silica at sub-zero temperature

Wed, 11/22/2023 - 19:21
The effect of antifreeze additives on concrete performance with and without nano-silica at sub-zero temperature
by Sedaghatdoost,A; Yasien,AM; Bassuoni,MT; 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 2023A5138 - INTERNET


The addition of antifreeze agents in concrete has been introduced as a practical solution to mitigate the noxious effects of cold weather on concrete. In this study, the effect of two types of economical and commercially available antifreeze additives: calcium nitrate-based (CN) and urea, on the performance of concrete with and without nano-silica cast and cured under a freezing temperature, was evaluated by setting time, strength development, durability performance, and thermogravimetry. The results showed that nano-modified concrete specimens containing CN acquired the highest mechanical and durability properties.

Streamlining Culvert Inspection: A Tablet-based Comprehensive Inventory and Condition Inspection System for Asset Management

Wed, 11/22/2023 - 18:50
Streamlining Culvert Inspection: A Tablet-based Comprehensive Inventory and Condition Inspection System for Asset Management
by Waseem,A; St. Michel,G; Taheri,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 2023A5137 - INTERNET


This paper presents a tablet-based inventory and condition inspection procedure for culvert assets using the data collection criteria outlined in the Culvert and Storm Drain System Inspection Manual (AASHTO, 2020). The procedure streamlines the inspection process by allowing for the digitization of data collection and real-time reporting, resulting in significant time and cost savings, improved accuracy, and repeatability. The procedure has been tested and implemented on the Alaska Highway in British Columbia, where approximately 2,200 culverts were inspected. Effective management of culvert assets requires reliable inventory and condition data on their structural and geometric characteristics and component conditions. The AASHTO Inspection Manual, published in 2020, addresses this need by updating the inspection and rating criteria, incorporating over 30 years of changes since its original publication in 1986. The rating system, based on the AASHTO Inspection Manual, includes the rating of culvert components such as roadway, seams, barrel condition, embankment, channel, end treatments, barrel alignment, joints, and seams. This component-level rating allows for a practical and efficient capital works program, as the entire culvert is rarely in poor condition. The approach utilizes an ArcGIS-based mobile solution to collect inventory and condition data, perform inspections, take notes, and share information with the office. The paper summarizes the methodology used, including the culvert inspection criteria, mobile solution, training workshops, data repeatability, collected inventory and condition data and development of a Multi-Criteria Decision Analysis Index. Digitizing data also allows for improved data analysis and asset management decision-making. Overall, this paper demonstrates the culvert data collection requirements and effectiveness of tablet-based technology in inspection and highlights the potential for similar applications for other agencies. The inventory, condition and MCDA data are suitable for developing a 20-year climate change informed culvert capital works replacement and adaptation program.

Replacement of the Chehalis Bridge – Design, Construction, and Demolition

Wed, 11/22/2023 - 18:27
Replacement of the Chehalis Bridge – Design, Construction, and Demolition
by Sohal,P; Hodgson,K; Saifuzzaman,M; Schueller,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 2023A5136 - INTERNET


The Chehalis Bridge serves the Morris Valley Road to cross the Chehalis River, 6 km North of HWY 7 and around 17 km West of Agassiz. The bridge is the only connection between the communities on both sides of the river and an important local link for the Sasquatch Mountain Resort and many campgrounds in the neighborhood. The over 70-years old timber through truss structure was due for replacement due to its deteriorated condition, limited roadway width, and modern hydraulic requirements. The construction method for the given span arrangement of the new bridge with one major main span and two symmetrical but relatively short side spans was decisive for the type of the new structure. Since a total traffic closure of the old bridge was not an option, the new bridge had to be realigned in parallel configuration right next to the old bridge. This paper describes the design and construction aspects of the new bridge in context to modern design philosophies as well as the engineering tasks behind the demolition of the old structure.

Reducing the Global Warming Potential of Structural Reinforced Concrete: A Case Study

Wed, 11/22/2023 - 18:12
Reducing the Global Warming Potential of Structural Reinforced Concrete: A Case Study
by Mottier,P; Kwiatek,C; Pepper,E; Pisirici,A; Ormsby,C.
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 2023A5135 - INTERNET


Overall, roughly a quarter of global greenhouse gas emissions are associated with the production of structural materials. Among those, approximately 7% are linked to the production of cement, which is one of the key ingredients in concrete, although it only counts for 10% of the concrete mix. Over the last 50 years, the worldwide production of cement has increased almost tenfold. In light of that number - which does not account for the other components of reinforced concrete- and in order to meet the requirements of the Paris Agreement, there needs to be a significant reduction of the carbon impact of the construction industry. Arup has led an initiative to provide recommendations on how to improve concrete mixes and reduce their Global Warming Potential (GWP). This paper presents the highlighted recommendations and presents as a case study the results obtained from a project that followed these recommendations. The case study involved the replacement of rail platforms using low-carbon precast curb units. A review of key factors and avenues to improve the carbon impact of concrete mixes is presented and recommendations are given. The application of those recommendations and their impact on the project are discussed. Setting environmental targets allowed a reduction of the GWP of the concrete mix used by 50% compared to the average in the precast concrete industry, without inducing costs or delays. The success of the initial project has led to these recommendations being used on a subsequent platform project at a different site.

Recycling Pavement for Highway 401 Expansion Project from Mississauga to Milton

Wed, 11/22/2023 - 16:19
Recycling Pavement for Highway 401 Expansion Project from Mississauga to Milton
by Van Dyk,H; James,B.
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 2023A5134 - INTERNET


West Corridor Constructors (WCC) was selected to design and build the Highway 401 Expansion Project. The project widened 18km of Highway 401 from Credit River in Mississauga to Regional Road 25 in Milton, from the 3 lanes in each direction, to 5 lane sections and 6 lane (collector/express) sections. Highway 401 is the busiest and most congested highway in North America; therefore, WCC required a strategy to maintain traffic during construction while reconstructing the median portion of the highway and keeping the project on schedule. Removing existing road material and transporting it off-site was not feasible due to the volume of traffic. Instead, a recycling concept was used to eliminate the need for trucking off-site. Asphalt and concrete were recycled on-site to produce granular material that could be used in the pavement structure, resulting in the conservation of materials and less fuel consumption.

Reality Capture of Hydraulics Infrastructure

Wed, 11/22/2023 - 15:57
Reality Capture of Hydraulics Infrastructure
by Wolfe,M; Masry,M; Ajumobi-Ode,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 2023A5133 - INTERNET


Topographic surveys of large culvert infrastructure have typically required significant financial investments, complicated logistics, and extensive data processing, all carried out by highly trained staff. More recently, technologies such as Light Detection and Ranging (LiDAR) – which measures the distance from a sensor using the Time-of-Flight of a light pulse - and multi-camera smartphones have reduced the costs and complexity needed to obtain high-resolution, 3D models of obscure built infrastructure. In the summer of 2022, the New Brunswick Department of Transportation and Infrastructure (NBDTI), Design Branch partnered with Modelar Technologies to evaluate the potential use of LiDAR-enabled iPhones as a tool for capturing 3D models of the interior of large culverts. The scanning software fuses multiple HD images, spatial orientation data and distance measurements from the iPhone’s LiDAR sensor to construct both a 3D point cloud and a textured, triangulated 3D surface model. The quality of the resulting 3D models depends on a number of factors, including the speed at which the scanning device is moving, the sensor resolution and the lighting conditions inside the culvert. This paper presents various aspects of this new reality capture collection system and compares the speed and cost to traditional surveying and data collection methods. The advantages (and possible drawbacks) of data collection by a wider range of staff at relatively lower cost than traditionally possible are explored. The accuracy and precision of these models are explored. Merging high-precision survey data with the mobile reality capture data and UAV 3D model to create a digital twin rendering of the asset will be shown. Additionally, the long-term goals for end-to-end processing workflows and data management are presented.

Re-evaluating Integral Abutment Bridge Design Practices after Three Decades of Standards in Ontario

Wed, 11/22/2023 - 15:43
Re-evaluating Integral Abutment Bridge Design Practices after Three Decades of Standards in Ontario
by Mermigas,KK.
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 2023A5132 - INTERNET


In 1993, the Ministry of Transportation in Ontario (MTO) released ‘Integral Abutment Bridges’, a report which documented 16 bridges constructed with integral abutments in Ontario. The report explained the theory of their design and proposed standard details. This document and the 1996 update which followed, set the stage for over 300 integral abutment bridges (hereafter IABs) built on provincial highways in Ontario since that time. Over the last three decades, extensive research, field trials and international experience has been gained and an update to the guideline is overdue. While standards benefit design engineers and constructors, they can be an impediment to progress and improvement. There is potential to improve detailing and expand the range of superstructure and foundation types which can be incorporated into integral bridges. This paper reflects on the design theory, the code requirements which have evolved with time and influenced the design details, and the field behaviour in service observed through visual observation and structural monitoring. Despite widespread use, there is still significant variation in the approach taken by design engineers and inconsistency in design assumptions. What is the appropriate earth pressure to assume in design, and how does it compare to actual pressures observed through site measurements? Is frost protection necessary? What types of foundations are appropriate for integral bridges and how flexible do foundations need to be? How should connections be detailed to ensure appropriate force transfer between girders and abutment wall, and between the abutment wall and piles? Working towards an update of the report, this paper reflects on challenges, presents examples which fall outside of the existing standard details, and attempts to answer these questions.

Performance-Based Specifications for Heavy-Duty Asphalt Mixes for Use in Southern Ontario

Tue, 11/21/2023 - 20:30
Performance-Based Specifications for Heavy-Duty Asphalt Mixes for Use in Southern Ontario
by Farashah,MK; Salehiashani,S; Varamini,S; Tighe,SL.
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 2023A5131 - INTERNET


Typically, a homogeneous pavement design is employed when constructing a road section. However, segments such as the approach intersection in a road section are subject to more severe loading due to the presence of static, accelerating, and decelerating traffic compared to the rest of the road section. The increase in traffic loading has negatively impacted the service life of approach intersections with high truck traffic volume in York Region. To ensure adequate durability, a more resilient pavement design is required for these approach intersections. Field results and past studies have indicated that relying solely on a volumetric design approach may not provide a comprehensive understanding of the asphalt mix under heavy traffic loading. Thus, the use of performance-related specifications could be utilized to produce high-performing asphalt mixes, resulting in an increased service life and reduced lifecycle cost. To evaluate this hypothesis, six Stone Mastic Asphalt (SMA) mixes, comprising three performance grade (PG) asphalt binders (PG70-28, PG76-28, and PG82-28) and two nominal maximum aggregate sizes (NMAS) of 9.5mm and 12.5mm, were produced under controlled laboratory conditions. The Disk-Shaped Compact Tension (DC(T)) Test was performed to characterize the low-temperature cracking resistance of the asphalt mixes, while the Illinois Flexibility Index Test (I-FIT) was used to evaluate the intermediate temperature cracking resistance. The Hamburg Wheel Tracking Test (HWTT) was employed to assess the shear resistance of the asphalt mixes. The results were compared to a recent plant-produced asphalt mix (WMA SP12.5FC2-PG70-28) used in York Region. A preliminary performance-based specification was developed to evaluate heavy-duty asphalt mixes, and a life cycle cost analysis was performed to determine the potential benefits of using a heavy-duty asphalt mix as a surface course over the conventional asphalt mix used in York Region.

Performance of Aged Asphalt Mastic Combining Active and Inert Filler Materials in Terms of Creep Recovery

Tue, 11/21/2023 - 20:08
Performance of Aged Asphalt Mastic Combining Active and Inert Filler Materials in Terms of Creep Recovery
by Feroz,SI; Mitra,D; Kabir,SKF; Hossain,K; Mehta,Y.
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 2023A5130 - INTERNET


Mastic is the main component of an asphalt structure that deforms when stress is applied. Substantial research has been done on the deformation and creep and recovery characteristics of asphalt mastic with varying filler proportions to develop a rheological parameter. Few research, however, has examined the combined impact of active and inert fillers. This study compares the creep recovery performance of asphalt mastics fabricated with the combination of different active and inert fillers containing modifier and anti-stripping agent. To understand the creep recovery characteristics of aged asphalt mastic, an experimental campaign of Multiple Stress Creep Recovery (MSCR) tests following AASHTO T 350 was performed using the Dynamic Shear Rheometer (DSR). This investigation used Styrene-Butadiene-Styrene (SBS) as modifiers to modify the neat PG 58-28 binder and Zycotherm as liquid anti-stripping agent. For fabricating the mastics, different proportions (10%,20%,30% by the weight of base binder) of Hydrated lime (HL) and Fly ash (FA) were selected as active fillers, whereas different proportions (70%,60%,50% by the weight of base binder) of Limestone (LS), Dolomite (DM) and Basalt (Ba) were selected as inert filler materials. The active and inert fillers were added in such a way that the Filler-Binder (F/B) ratio remains 0.8. Rolling Thin-Film Oven (RTFO) protocol was applied to simulate construction and laying time oxidative aging. The performance of these mastics was compared using non-recoverable creep compliance, stress sensitivity analysis, and percent recovery analysis. AASHTO M 332 specifications have been used to classify all the mastics based on the Jnr value at 3.2 kPa and stress sensitivity. In addition, polymer method MSCR curve specified by the Asphalt Institute (AI) were employed to interpret the test results. Based on the analysis of experimental data, active filler HL produced better creep recovery performance compared to FA, and when combined with inert filler LS, it showed the best performance. The combined effect of 10%HL and 70%LS modified with SBS containing Zycotherm was predominant and satisfied all the creep recovery performance requirements.

Performance Comparison of CIR and CIREAM in Ontario

Tue, 11/21/2023 - 19:48
Performance Comparison of CIR and CIREAM in Ontario
by Chan,S; Chen,SI; Gumisiriza,G; 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 2023A5129 - INTERNET


In 2003, the first trial of Cold In-Place Recycled Expanded Asphalt Mix (CIREAM) was constructed adjacent to a Cold In-Place Recycling (CIR) mix on Highway 7, east of Perth, Ontario. The major difference between the two processes is that CIR uses emulsion and CIREAM uses foamed asphalt as binding agent. From this successful trial, CIR and CIREAM have become established cold recycling pavement treatments used by Ministry of Transportation Ontario (MTO). After 20 years in service, this section of highway has reached its end of lifecycle. Continuous performance monitoring of these two sections have been performed over the years. Laboratory testing was carried out to determine the resilient modulus and indirect tensile strength (ITS) of the mixes. Falling Weight Deflectometer (FWD) testing was carried out to monitor the performance, and Ultrasonic Pulse Velocity (UPV) testing was completed to assess the overall quality of the mixes. In addition, typical pavement condition performance monitoring was done using the Ministry’s Automated Road Analyzer (ARAN). This paper summarizes the pavement performance conditions and the results over the years and provides documentation of the end of lifecycle of the two sections. The results confirmed both CIR and CIREAM are performing similarly after 20 years of service.

Ontario’s Reduced Load Period (RLP) Onset and Removal Prediction Model

Tue, 11/21/2023 - 19:21
Ontario’s Reduced Load Period (RLP) Onset and Removal Prediction Model
by Leung,YTF; Liu,Y; Chan,S; 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 2023A5128 - INTERNET


In the spring, the frost formed in the pavement subsurface structure starts thawing and pavement becomes weaker. Heavy loads on the weakened roads can cause substantial damage and lead to pavement life reduction or road failure. To ensure the integrity of roadway structures during spring-thaw season, the Ontario Ministry of Transportation (MTO) and municipalities in Ontario enforces reduced load restriction on certain provincial highways and municipal roads in according with the Highway Traffic Act. Currently, most municipalities implemented a fixed-date approach for the reduced load period (RLP). However, concerns have been raised by municipalities and the trucking industry that this fixed RLP does not accurately reflect the actual spring-thaw condition. In an effort to reduce economic red tape and hardship for the trucking industry and to support the municipalities in protecting their road infrastructure, the MTO propose a calibrated predictive approach for determining the start and end dates of the RLP. This predictive approach utilizes representative weather data and the response of pavement structure. Based on assessment of the RLP protocols from MTO and neighboring agencies, the MTO suggests dividing the province into four RLP zones and employing the Cumulative Thawing Index (CTI) method to forecast the start and removal dates of the RLP. This paper outlines the rationale behind the proposed methodology, which involves utilizing field measurement such as subsurface temperature, moisture content, borehole data, and pavement deflection to establish CTI thresholds for each specific zone’s start and removal dates. This paper also highlights the calibration, verification, recommendations, and the subsequent steps necessary for implementing the proposed RLP management solution, which seeks to strike a balance between the requirements of trucking industry and the objectives of road agencies.

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