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Several transportation agencies in Canada are currently relying on volumetric properties of asphalt mixtures to accept or reject the final mix design. The existence of various pavement defects on Canadian roads indicates that volumetric mix design procedure alone does not guarantee adequate long-term pavement performance. Therefore, transportation agencies in Manitoba are finding ways to increase durability of their asphalt mixtures to accomplish a road network that is more sustainable, safer, and more economical. The balanced mix design (BMD) approach integrates two or more performance test criteria into mix design and acceptance to produce asphalt mixtures that are resistant to cracking and permanent deformation. The objective of this study is to assess cracking and rutting performance of plant-produced asphalt mixtures as well as fractionated reclaimed asphalt pavement (RAP) mixtures to validate current volumetric mix design methods and investigate ways to optimize mix performance for moving towards a BMD. Fractionated RAP mixtures were produced in the laboratory and plant-produced mixtures were collected from different pavement construction projects to prepare specimens for cracking and rutting evaluation. Cracking performance was determined using the Illinois flexibility index test and rutting performance was determined using the Hamburg wheel-tracking test. Results showed that polymer-modified binders, recycled materials, and reduction of nominal maximum aggregate size contributed to better rutting performance. In addition, RAP fractionation technology showed a promising effort in making asphalt mixtures move towards a BMD. Conversely, limestone aggregates and recycled asphalt shingles reduced cracking resistance and did not lead to a BMD.

Several transportation agencies in Canada are currently relying on volumetric properties of asphalt mixtures to accept or reject the final mix design. The existence of various pavement defects on Canadian roads indicates that volumetric mix design procedure alone does not guarantee adequate long-term pavement performance. Therefore, transportation agencies in Manitoba are finding ways to increase durability of their asphalt mixtures to accomplish a road network that is more sustainable, safer, and more economical. The balanced mix design (BMD) approach integrates two or more performance test criteria into mix design and acceptance to produce asphalt mixtures that are resistant to cracking and permanent deformation. The objective of this study is to assess cracking and rutting performance of plant-produced asphalt mixtures as well as fractionated reclaimed asphalt pavement (RAP) mixtures to validate current volumetric mix design methods and investigate ways to optimize mix performance for moving towards a BMD. Fractionated RAP mixtures were produced in the laboratory and plant-produced mixtures were collected from different pavement construction projects to prepare specimens for cracking and rutting evaluation. Cracking performance was determined using the Illinois flexibility index test and rutting performance was determined using the Hamburg wheel-tracking test. Results showed that polymer-modified binders, recycled materials, and reduction of nominal maximum aggregate size contributed to better rutting performance. In addition, RAP fractionation technology showed a promising effort in making asphalt mixtures move towards a BMD. Conversely, limestone aggregates and recycled asphalt shingles reduced cracking resistance and did not lead to a BMD.

Remote communities in Canada still rely on diesel generators for their heating and electricity. Diesel combustion produces emissions of greenhouse gases (GHG) and other hazardous pollutants such as nitrogen oxides (NOx), carbon monoxide (CO), unburned hydrocarbons (HC) and particulate matter (PM) which affect negatively the environment and human health. Governmental regulations have forced manufacturers of fossil fuel powered systems to reduce emissions. Fuel switching from petroleum diesel to sustainable fuels such as syngas, which is a gaseous fuel that can be produced from local biomass through gasification process, has the potential to substitute diesel fuel in numerous engineering power systems and consequently reduce undesirable emissions. For instance, syngas can substitute a large quantity of diesel fuel in dual-fuel diesel engines and hence significantly reduce emissions. With a self-ignition temperature typically exceeding 500°C, sole syngas cannot be used in compression ignition (CI) engines. However, the utilization of syngas in CI engines can be achieved through dual-fuel combustion mode where only a small amount of diesel is needed to initiate ignition. The primary objective of this thesis is to thoroughly investigate the combustion and emission performance of a four-cylinder syngas-diesel dual-fuel generator under constant load conditions. This is achieved by varying syngas flow rates and composition, and optimizing direct injection (DI) strategies and exhaust gas recirculation (EGR) rate. The unique aspect of this research is that experiments were performed on a modern multi-cylinder diesel-fueled generator with minimal modifications, making it more relevant for practical applications. The findings from this study can potentially be directly applied to real-world scenarios, where existing diesel generators can be retrofitted to accommodate syngas utilization in dual-fuel combustion mode.

The stability of river banks has always been a concern for land-use planners, stakeholders as well as the City of Winnipeg. Construction activities can generate different types of stress waves and ground vibrations. Operations such as blasting, pile driving, dynamic compaction for ground improvement purposes, and in-situ geotechnical investigation testing such as the Standard Penetration Test are the primary sources of construction-induced ground vibrations. To address slope instability, several techniques have been employed. Enhancing the slope stability can be done by building toe berms, armouring the slope along the waterline, constructing granular shear keys, and soil nailing. Constructing retaining walls with anchoring is another expensive but effective measure. One of the strategies adopted by the City of Winnipeg to mitigate the instability of the riverbank is to install rockfill columns. However, the installation of rockfill columns using vibro-impact sources, on the contrary, can generate ground vibrations leading to instability of the slopes due to compromising the ground conditions and altering the pore water pressure. This research aims to study the instability of river banks subjected to construction-induced vibrations. The soil deformations, variations of pore water pressure, and the level of vibrations of the Seine riverbank in the City of Winnipeg were monitored prior to, during the stabilization, and after installing a set of rockfill columns using sensing instruments including inclinometers, vibrating wire piezometers, accelerometers and geophones. The Finite Difference Method is used to simulate the impacts of vibrations numerically and the results compared to the field monitoring data. Also, the effects of construction-induced vibrations on global and local instability due to the shear failure in the soil layers are outlined. The numerical analysis demonstrated that despite the construction-induced vibrations remaining below the prescribed vibrat

The challenges posed by Canada's aging infrastructure and limited economic resources have underscored the need for proactive measures to address the vulnerabilities inherent in its bridge systems. This study seeks to develop a comprehensive framework tailored to the evaluation of risk factors associated with flooding and overweight traffic on typical highway bridges in Manitoba. The primary objective of this research is to establish a robust methodology for assessing risk values arising from the combined effects of flooding and overweight traffic on bridge structures. To this end, the study engages in a thorough analysis of historical flood data to pinpoint flood-prone zones. Concurrently, historical data pertaining to Average Annual Daily Traffic Volume (AADTT) and Overweight (OW) percentages are examined to ascertain the frequency of overloading risk for bridges due to overweight traffic. The investigation extends to the determination of overtopping levels for individual bridges, complemented by the establishment of vertical clearance thresholds spanning a range from 3 to 12.6 meters. Additionally, the research investigates the interplay between OW (%) and AADTT, revealing a direct relationship wherein heightened truck traffic contributes to an elevated percentage of excessive loading on bridges. Consequently, this heightened loading exacerbates the risk of bridge failures. The results of the analysis show for five different levels of flooding, a probability of failure ranging between 0.0155 and 0.0081. Bridges close to the Red River are at higher risk due to more water flow. The probability of failure due to overloading ranges from 3.74e-09 to 1.29e-08. The most vulnerable area in Manitoba is along the Trans-Canada highway and the north-south corridors near Winnipeg. This highlights the importance of considering specific locations when designing and maintaining bridges to ensure their safety.

Polynomial time dynamic programming algorithms play a crucial role in the design, analysis and engineering of nucleic acid systems including DNA computers and DNA/RNA nanostructures. However, in complex multistranded or pseudoknotted systems, computing the minimum free energy (MFE), and partition function of nucleic acid systems is NP-hard. Despite this, multistranded and/or pseudoknotted systems represent some of the most utilised and successful systems in the field. This leaves open the tempting possibility that many of the kinds of multistranded and/or pseudoknotted systems we wish to engineer actually fall into restricted classes, that do in fact have polynomial time algorithms, but we've just not found them yet. Here, we give polynomial time algorithms for MFE and partition function calculation for a restricted kind of multistranded system called the 1D scaffolded DNA computer. This model of computation thermodynamically favours correct outputs over erroneous states, simulates finite state machines in 1D and Boolean circuits in 2D, and is amenable to DNA storage applications. In an effort to begin to ask the question of whether we can naturally compare the expressivity of nucleic acid systems based on the computational complexity of prediction of their preferred energetic states, we show our MFE problem is in logspace (the complexity class L), making it perhaps one of the simplest known, natural, nucleic acid MFE problems. Finally, we provide a stochastic kinetic simulator for the 1D scaffolded DNA computer and evaluate strategies for efficiently speeding up this thermodynamically favourable system in a constant-temperature kinetic regime.

The challenges posed by Canada's aging infrastructure and limited economic resources have underscored the need for proactive measures to address the vulnerabilities inherent in its bridge systems. This study seeks to develop a comprehensive framework tailored to the evaluation of risk factors associated with flooding and overweight traffic on typical highway bridges in Manitoba. The primary objective of this research is to establish a robust methodology for assessing risk values arising from the combined effects of flooding and overweight traffic on bridge structures. To this end, the study engages in a thorough analysis of historical flood data to pinpoint flood-prone zones. Concurrently, historical data pertaining to Average Annual Daily Traffic Volume (AADTT) and Overweight (OW) percentages are examined to ascertain the frequency of overloading risk for bridges due to overweight traffic. The investigation extends to the determination of overtopping levels for individual bridges, complemented by the establishment of vertical clearance thresholds spanning a range from 3 to 12.6 meters. Additionally, the research investigates the interplay between OW (%) and AADTT, revealing a direct relationship wherein heightened truck traffic contributes to an elevated percentage of excessive loading on bridges. Consequently, this heightened loading exacerbates the risk of bridge failures. The results of the analysis show for five different levels of flooding, a probability of failure ranging between 0.0155 and 0.0081. Bridges close to the Red River are at higher risk due to more water flow. The probability of failure due to overloading ranges from 3.74e-09 to 1.29e-08. The most vulnerable area in Manitoba is along the Trans-Canada highway and the north-south corridors near Winnipeg. This highlights the importance of considering specific locations when designing and maintaining bridges to ensure their safety.

The stability of river banks has always been a concern for land-use planners, stakeholders as well as the City of Winnipeg. Construction activities can generate different types of stress waves and ground vibrations. Operations such as blasting, pile driving, dynamic compaction for ground improvement purposes, and in-situ geotechnical investigation testing such as the Standard Penetration Test are the primary sources of construction-induced ground vibrations. To address slope instability, several techniques have been employed. Enhancing the slope stability can be done by building toe berms, armouring the slope along the waterline, constructing granular shear keys, and soil nailing. Constructing retaining walls with anchoring is another expensive but effective measure. One of the strategies adopted by the City of Winnipeg to mitigate the instability of the riverbank is to install rockfill columns. However, the installation of rockfill columns using vibro-impact sources, on the contrary, can generate ground vibrations leading to instability of the slopes due to compromising the ground conditions and altering the pore water pressure. This research aims to study the instability of river banks subjected to construction-induced vibrations. The soil deformations, variations of pore water pressure, and the level of vibrations of the Seine riverbank in the City of Winnipeg were monitored prior to, during the stabilization, and after installing a set of rockfill columns using sensing instruments including inclinometers, vibrating wire piezometers, accelerometers and geophones. The Finite Difference Method is used to simulate the impacts of vibrations numerically and the results compared to the field monitoring data. Also, the effects of construction-induced vibrations on global and local instability due to the shear failure in the soil layers are outlined. The numerical analysis demonstrated that despite the construction-induced vibrations remaining below the prescribed vibrat

Remote communities in Canada still rely on diesel generators for their heating and electricity. Diesel combustion produces emissions of greenhouse gases (GHG) and other hazardous pollutants such as nitrogen oxides (NOx), carbon monoxide (CO), unburned hydrocarbons (HC) and particulate matter (PM) which affect negatively the environment and human health. Governmental regulations have forced manufacturers of fossil fuel powered systems to reduce emissions. Fuel switching from petroleum diesel to sustainable fuels such as syngas, which is a gaseous fuel that can be produced from local biomass through gasification process, has the potential to substitute diesel fuel in numerous engineering power systems and consequently reduce undesirable emissions. For instance, syngas can substitute a large quantity of diesel fuel in dual-fuel diesel engines and hence significantly reduce emissions. With a self-ignition temperature typically exceeding 500°C, sole syngas cannot be used in compression ignition (CI) engines. However, the utilization of syngas in CI engines can be achieved through dual-fuel combustion mode where only a small amount of diesel is needed to initiate ignition. The primary objective of this thesis is to thoroughly investigate the combustion and emission performance of a four-cylinder syngas-diesel dual-fuel generator under constant load conditions. This is achieved by varying syngas flow rates and composition, and optimizing direct injection (DI) strategies and exhaust gas recirculation (EGR) rate. The unique aspect of this research is that experiments were performed on a modern multi-cylinder diesel-fueled generator with minimal modifications, making it more relevant for practical applications. The findings from this study can potentially be directly applied to real-world scenarios, where existing diesel generators can be retrofitted to accommodate syngas utilization in dual-fuel combustion mode.

The challenges posed by Canada's aging infrastructure and limited economic resources have underscored the need for proactive measures to address the vulnerabilities inherent in its bridge systems. This study seeks to develop a comprehensive framework tailored to the evaluation of risk factors associated with flooding and overweight traffic on typical highway bridges in Manitoba. The primary objective of this research is to establish a robust methodology for assessing risk values arising from the combined effects of flooding and overweight traffic on bridge structures. To this end, the study engages in a thorough analysis of historical flood data to pinpoint flood-prone zones. Concurrently, historical data pertaining to Average Annual Daily Traffic Volume (AADTT) and Overweight (OW) percentages are examined to ascertain the frequency of overloading risk for bridges due to overweight traffic. The investigation extends to the determination of overtopping levels for individual bridges, complemented by the establishment of vertical clearance thresholds spanning a range from 3 to 12.6 meters. Additionally, the research investigates the interplay between OW (%) and AADTT, revealing a direct relationship wherein heightened truck traffic contributes to an elevated percentage of excessive loading on bridges. Consequently, this heightened loading exacerbates the risk of bridge failures. The results of the analysis show for five different levels of flooding, a probability of failure ranging between 0.0155 and 0.0081. Bridges close to the Red River are at higher risk due to more water flow. The probability of failure due to overloading ranges from 3.74e-09 to 1.29e-08. The most vulnerable area in Manitoba is along the Trans-Canada highway and the north-south corridors near Winnipeg. This highlights the importance of considering specific locations when designing and maintaining bridges to ensure their safety.

The stability of river banks has always been a concern for land-use planners, stakeholders as well as the City of Winnipeg. Construction activities can generate different types of stress waves and ground vibrations. Operations such as blasting, pile driving, dynamic compaction for ground improvement purposes, and in-situ geotechnical investigation testing such as the Standard Penetration Test are the primary sources of construction-induced ground vibrations. To address slope instability, several techniques have been employed. Enhancing the slope stability can be done by building toe berms, armouring the slope along the waterline, constructing granular shear keys, and soil nailing. Constructing retaining walls with anchoring is another expensive but effective measure. One of the strategies adopted by the City of Winnipeg to mitigate the instability of the riverbank is to install rockfill columns. However, the installation of rockfill columns using vibro-impact sources, on the contrary, can generate ground vibrations leading to instability of the slopes due to compromising the ground conditions and altering the pore water pressure. This research aims to study the instability of river banks subjected to construction-induced vibrations. The soil deformations, variations of pore water pressure, and the level of vibrations of the Seine riverbank in the City of Winnipeg were monitored prior to, during the stabilization, and after installing a set of rockfill columns using sensing instruments including inclinometers, vibrating wire piezometers, accelerometers and geophones. The Finite Difference Method is used to simulate the impacts of vibrations numerically and the results compared to the field monitoring data. Also, the effects of construction-induced vibrations on global and local instability due to the shear failure in the soil layers are outlined. The numerical analysis demonstrated that despite the construction-induced vibrations remaining below the prescribed vibrat

Remote communities in Canada still rely on diesel generators for their heating and electricity. Diesel combustion produces emissions of greenhouse gases (GHG) and other hazardous pollutants such as nitrogen oxides (NOx), carbon monoxide (CO), unburned hydrocarbons (HC) and particulate matter (PM) which affect negatively the environment and human health. Governmental regulations have forced manufacturers of fossil fuel powered systems to reduce emissions. Fuel switching from petroleum diesel to sustainable fuels such as syngas, which is a gaseous fuel that can be produced from local biomass through gasification process, has the potential to substitute diesel fuel in numerous engineering power systems and consequently reduce undesirable emissions. For instance, syngas can substitute a large quantity of diesel fuel in dual-fuel diesel engines and hence significantly reduce emissions. With a self-ignition temperature typically exceeding 500°C, sole syngas cannot be used in compression ignition (CI) engines. However, the utilization of syngas in CI engines can be achieved through dual-fuel combustion mode where only a small amount of diesel is needed to initiate ignition. The primary objective of this thesis is to thoroughly investigate the combustion and emission performance of a four-cylinder syngas-diesel dual-fuel generator under constant load conditions. This is achieved by varying syngas flow rates and composition, and optimizing direct injection (DI) strategies and exhaust gas recirculation (EGR) rate. The unique aspect of this research is that experiments were performed on a modern multi-cylinder diesel-fueled generator with minimal modifications, making it more relevant for practical applications. The findings from this study can potentially be directly applied to real-world scenarios, where existing diesel generators can be retrofitted to accommodate syngas utilization in dual-fuel combustion mode.

The use of recycled plastics in asphalt has gained more attention in the last few years. The objective of this study is to evaluate the performance of asphalt binders that have been modified using recycled polyethylene-based plastic pellets (RPE) using the Superpave Performance Grading and the Multiple Stress Creep and Recovery (MSCR) Tests. The study will also focus on the influence of the chemical modifiers Elvaloy and Polyphosphoric Acid (PPA) on the performance of the RPE-modified binders. Two different types of RPE pellets were blended in a PG 58-28 base binder during this study. Eight (8) different modified blends were developed, four (4) of which were blended with only RPE pellets and the other four (4) included the RPE, Elvaloy, and PPA modifiers. The dosages of the RPE pellets were 2% and 4% by weight of the mix, while the Elvaloy and PPA had fixed dosages of 1% and 0.002% by weight of the mix. The study showed that the addition of the RPE to the asphalt binders improved the high-temperature performance of the binders. The 2% dosage of the RPE led to a high temperature-grade increment of the binder (from PG-58 to PG-64) while the 4% dosage led to the increment of the high-temperature grade by 2-levels (PG-58 to PG-70). The presence of the Elvaloy and PPA also affected the performance of the binder in very similar ways as compared to the RPE only. The RPE, Elvaloy and PPA modified binders showed marginally better rutting resistance than the binder with RPE only. The fatigue resistance of the modified binders was also improved after the modification process. The low-temperature performance of the modified binders was minimally affected after the modification process. The modified binders showed increased stiffnesses at low temperatures, however, the increase in stiffness was not sufficient enough to alter the low-temperature grades of the modified binders.

Realizing functional space systems using flight-tested components is problematic in developing economies, as such components are costly for most institutions to sponsor. The B.Sc. project, Subsystems for 2nd Iteration Cairo University Cube-Satellite, addresses technology demonstration using commercially available electronics and low cost computing platforms, such as Android phones and Raspberry Pi Linux micro-computer as computing hardware. As for software, the project makes use of open-source modules and locally developed code to implement needed functionalities, in addition to a mechanism to operate a virtual desktop Linux OS in parallel to an Android application. The paper aims to demonstrate the significance, operation design, and problem solving of such approaches. The paper concludes with future prospects for improving upon the proposed computing systems

The use of recycled plastics in asphalt has gained more attention in the last few years. The objective of this study is to evaluate the performance of asphalt binders that have been modified using recycled polyethylene-based plastic pellets (RPE) using the Superpave Performance Grading and the Multiple Stress Creep and Recovery (MSCR) Tests. The study will also focus on the influence of the chemical modifiers Elvaloy and Polyphosphoric Acid (PPA) on the performance of the RPE-modified binders. Two different types of RPE pellets were blended in a PG 58-28 base binder during this study. Eight (8) different modified blends were developed, four (4) of which were blended with only RPE pellets and the other four (4) included the RPE, Elvaloy, and PPA modifiers. The dosages of the RPE pellets were 2% and 4% by weight of the mix, while the Elvaloy and PPA had fixed dosages of 1% and 0.002% by weight of the mix. The study showed that the addition of the RPE to the asphalt binders improved the high-temperature performance of the binders. The 2% dosage of the RPE led to a high temperature-grade increment of the binder (from PG-58 to PG-64) while the 4% dosage led to the increment of the high-temperature grade by 2-levels (PG-58 to PG-70). The presence of the Elvaloy and PPA also affected the performance of the binder in very similar ways as compared to the RPE only. The RPE, Elvaloy and PPA modified binders showed marginally better rutting resistance than the binder with RPE only. The fatigue resistance of the modified binders was also improved after the modification process. The low-temperature performance of the modified binders was minimally affected after the modification process. The modified binders showed increased stiffnesses at low temperatures, however, the increase in stiffness was not sufficient enough to alter the low-temperature grades of the modified binders.

Under loading and environmental conditions, the brittle nature of conventional concrete flatwork infrastructure (e.g. pavements/bridge decks) may negatively affect its performance due to susceptibility to excessive cracking, requiring costly rehabilitation or replacement of damaged sections. Thus, this thesis aimed at developing and testing a novel type of high-performance cementitious composites. Nano-modified cementitious composites comprising 50% fly ash or slag and reinforced with an innovative type of macro-fibers [basalt fiber pellets (BFP)] were developed and extensively studied. The consistency and flowability/flowability retention of the composites as well as setting times were investigated. The mechanical performance of the composites was tested under static and dynamic (Split Hopkinson Pressure Bar) loading schemes. Moreover, the performance of the cementitious composites under aggravated (alkaline and salt-frost) exposures was comprehensively explored. To investigate potential of these composites for repair and overlay applications in concrete flatwork, thermal, elastic, and mechanical compatibility of the cementitious composites with conventional concrete paving mixture as well as their suitability for bonded overlay systems were experimentally and numerically studied. The results showed that the nano-modified composites with 6% nano-silica exhibited enhanced mechanical performance at both early- and late-ages. Moreover, they revealed the efficacy of BFP in reinforcing the cementitious composites and highlighted their role at enhancing the post-cracking performance in terms of energy absorption capacity and strain at failure. While alkaline exposure provided favorable conditions for the binders’ reactivity, this was accompanied by reduction of ductility of composites due to pellets’ degradation. The matrix of the composites deteriorated physically and/or chemically under the salt-frost exposure, albeit to different extents according to the binder type.

Non-destructive testing (NDT) plays an important role in the engineering, construction, and geophysical fields. The application of NDT in civil engineering is broad from quality control, structural health monitoring of infrastructure, geophysical and geotechnical field investigation and material characterization to detection of underground anomaly, among others. One of the frequently used NDT techniques for the characterization of geomaterials is based on the propagation of stress waves generated by an excitation source. However, the existing signal interpretation methods still predominantly rely on empirical relations or subjective judgements that are insufficient for the characterization of multiphase complex geomaterials. This research aims to develop novel physics-based signal interpretation methods to characterize physical and mechanical properties of multiphase geomaterials in both field and laboratory investigation scales. Several hybrid inverse and poromechanical models are developed to characterize dry, saturated, and frozen geomaterials subject to stress waves. First, a highly-efficient semi-analytical elastodynamic forward solver was proposed for the Multichannel Analysis of Surface Waves using the spectral element technique to determine effectively and efficiently the soil stratigraphy as well as soil properties. Next, a coupled piezoelectric and solid mechanics model is proposed to study the real response of the bender element (BE) and its interaction with soil samples in the BE test. A comprehensive laboratory investigation is also performed to better understand the response of the BEs inside different soil types. Then, a two-phase poromechanics-based signal interpretation model is developed for laboratory-scale ultrasonic testing to determine the physical and mechanical properties of saturated soil samples based on the distribution of stress waves. Subsequently, a three-phase poromechanical transfer function model is developed using the spectral eleme

Under loading and environmental conditions, the brittle nature of conventional concrete flatwork infrastructure (e.g. pavements/bridge decks) may negatively affect its performance due to susceptibility to excessive cracking, requiring costly rehabilitation or replacement of damaged sections. Thus, this thesis aimed at developing and testing a novel type of high-performance cementitious composites. Nano-modified cementitious composites comprising 50% fly ash or slag and reinforced with an innovative type of macro-fibers [basalt fiber pellets (BFP)] were developed and extensively studied. The consistency and flowability/flowability retention of the composites as well as setting times were investigated. The mechanical performance of the composites was tested under static and dynamic (Split Hopkinson Pressure Bar) loading schemes. Moreover, the performance of the cementitious composites under aggravated (alkaline and salt-frost) exposures was comprehensively explored. To investigate potential of these composites for repair and overlay applications in concrete flatwork, thermal, elastic, and mechanical compatibility of the cementitious composites with conventional concrete paving mixture as well as their suitability for bonded overlay systems were experimentally and numerically studied. The results showed that the nano-modified composites with 6% nano-silica exhibited enhanced mechanical performance at both early- and late-ages. Moreover, they revealed the efficacy of BFP in reinforcing the cementitious composites and highlighted their role at enhancing the post-cracking performance in terms of energy absorption capacity and strain at failure. While alkaline exposure provided favorable conditions for the binders’ reactivity, this was accompanied by reduction of ductility of composites due to pellets’ degradation. The matrix of the composites deteriorated physically and/or chemically under the salt-frost exposure, albeit to different extents according to the binder type.

Non-destructive testing (NDT) plays an important role in the engineering, construction, and geophysical fields. The application of NDT in civil engineering is broad from quality control, structural health monitoring of infrastructure, geophysical and geotechnical field investigation and material characterization to detection of underground anomaly, among others. One of the frequently used NDT techniques for the characterization of geomaterials is based on the propagation of stress waves generated by an excitation source. However, the existing signal interpretation methods still predominantly rely on empirical relations or subjective judgements that are insufficient for the characterization of multiphase complex geomaterials. This research aims to develop novel physics-based signal interpretation methods to characterize physical and mechanical properties of multiphase geomaterials in both field and laboratory investigation scales. Several hybrid inverse and poromechanical models are developed to characterize dry, saturated, and frozen geomaterials subject to stress waves. First, a highly-efficient semi-analytical elastodynamic forward solver was proposed for the Multichannel Analysis of Surface Waves using the spectral element technique to determine effectively and efficiently the soil stratigraphy as well as soil properties. Next, a coupled piezoelectric and solid mechanics model is proposed to study the real response of the bender element (BE) and its interaction with soil samples in the BE test. A comprehensive laboratory investigation is also performed to better understand the response of the BEs inside different soil types. Then, a two-phase poromechanics-based signal interpretation model is developed for laboratory-scale ultrasonic testing to determine the physical and mechanical properties of saturated soil samples based on the distribution of stress waves. Subsequently, a three-phase poromechanical transfer function model is developed using the spectral eleme

Photogrammetry conducted with images obtained via Remotely Piloted Aircraft (RPA) has revolutionized the field of land surface monitoring. It is particularly useful where land surface data collection would otherwise be expensive or dangerous. The monitoring of fluvial ice covers can be time-intensive, dangerous, and costly. Fluvial ice roughness is a sensitive parameter in hydraulic models and is difficult to measure using traditional field methods. This research hypothesizes that the surface roughness of a fluvial ice cover is indicative of subsurface roughness. The hypothesis was tested through a comparison of ice roughness determined through inverse hydraulic modeling and ice roughness determined through statistical analysis of ice surfaces derived through RPA-photogrammetry. Hydraulic and topographic data were collected over two years of field research on the Dauphin River in Manitoba, Canada. Various statistical metrics were used to represent the roughness of the surfaces. Strong correlation was identified in the comparison of ice cover roughness determined through RPA-photogrammetry and roughness calculated via the Nezhikhovskiy equation, as well as ice thickness. Some correlation was observed between ice cover roughness observed through RPA-photogrammetry and ice roughness predicted through inverse hydraulic modeling. The inter-quartile range (IQR) was the most representative roughness metric. The maximum peak value performed better in some cases, but this metric would be heavily influenced by outliers, and was rejected as a representative metric. Three distinct forms of surface ice roughness were noted: rough, smooth, and ridged. Statistical properties of elevation data of fluvial ice covers were calculated, none were found to be normally distributed. K-means clustering analysis was used to group cover into two categories, which were interpreted as rough and smooth ice. The IQR of the rough and smooth categories were 0.07 - 0.12 m and 0.01 - 0.05 m, respecti

Photogrammetry conducted with images obtained via Remotely Piloted Aircraft (RPA) has revolutionized the field of land surface monitoring. It is particularly useful where land surface data collection would otherwise be expensive or dangerous. The monitoring of fluvial ice covers can be time-intensive, dangerous, and costly. Fluvial ice roughness is a sensitive parameter in hydraulic models and is difficult to measure using traditional field methods. This research hypothesizes that the surface roughness of a fluvial ice cover is indicative of subsurface roughness. The hypothesis was tested through a comparison of ice roughness determined through inverse hydraulic modeling and ice roughness determined through statistical analysis of ice surfaces derived through RPA-photogrammetry. Hydraulic and topographic data were collected over two years of field research on the Dauphin River in Manitoba, Canada. Various statistical metrics were used to represent the roughness of the surfaces. Strong correlation was identified in the comparison of ice cover roughness determined through RPA-photogrammetry and roughness calculated via the Nezhikhovskiy equation, as well as ice thickness. Some correlation was observed between ice cover roughness observed through RPA-photogrammetry and ice roughness predicted through inverse hydraulic modeling. The inter-quartile range (IQR) was the most representative roughness metric. The maximum peak value performed better in some cases, but this metric would be heavily influenced by outliers, and was rejected as a representative metric. Three distinct forms of surface ice roughness were noted: rough, smooth, and ridged. Statistical properties of elevation data of fluvial ice covers were calculated, none were found to be normally distributed. K-means clustering analysis was used to group cover into two categories, which were interpreted as rough and smooth ice. The IQR of the rough and smooth categories were 0.07 - 0.12 m and 0.01 - 0.05 m, respecti

Warm Mix Asphalt (WMA) technology has the capability of lowering the temperature at which the asphalt is mixed and compacted by 30°C or more without compromising the performance of asphalt pavement. The reduced difference between asphalt mix and ambient temperature results in a lower cooling rate thus allows for long haul, sufficient compaction time and late season projects compared to the conventional Hot Mix Asphalt (HMA). In northern climate, asphalt paving season is relatively short and paving is often done late in the season when weather conditions are less than ideal. The potential benefit of WMA, among others, is an extended paving season for the City of Winnipeg. Reduction in production temperature also comes with other positive impacts both economically and environmentally. The objective of this study is to evaluate the installation of WMA, compile experiences with this technology and evaluate their effects on construction methods and performance. The study further attempts to evaluate the effectiveness of the WMA chemical additives and its dosage rate as liquid anti-strip agents on the properties of WMA mixtures through field and laboratory testing programs. In addition to the overall effectiveness of WMA, the study aimed to evaluate its economic cost relative to Hot Mix Asphalt (HMA). A chemical additive was used at three different dosages (0.3, 0.5 and 0.7 percent by weight of asphalt cement). The additive has the ability to improve mixing, aggregate coating, workability, compaction and adhesion with no change in materials or job mix formula required. The study showed that WMA could be successfully placed using conventional HMA paving practices and procedures. Among the different additive dosages used, 0.5% had a better overall performance. The moisture sensitivity tests indicated the highest Tensile Strength Ratio (TSR) at this dosage, suggesting the lowest moisture damage susceptibility. All four mixtures had low rutting resistance potential with no si

Warm Mix Asphalt (WMA) technology has the capability of lowering the temperature at which the asphalt is mixed and compacted by 30°C or more without compromising the performance of asphalt pavement. The reduced difference between asphalt mix and ambient temperature results in a lower cooling rate thus allows for long haul, sufficient compaction time and late season projects compared to the conventional Hot Mix Asphalt (HMA). In northern climate, asphalt paving season is relatively short and paving is often done late in the season when weather conditions are less than ideal. The potential benefit of WMA, among others, is an extended paving season for the City of Winnipeg. Reduction in production temperature also comes with other positive impacts both economically and environmentally. The objective of this study is to evaluate the installation of WMA, compile experiences with this technology and evaluate their effects on construction methods and performance. The study further attempts to evaluate the effectiveness of the WMA chemical additives and its dosage rate as liquid anti-strip agents on the properties of WMA mixtures through field and laboratory testing programs. In addition to the overall effectiveness of WMA, the study aimed to evaluate its economic cost relative to Hot Mix Asphalt (HMA). A chemical additive was used at three different dosages (0.3, 0.5 and 0.7 percent by weight of asphalt cement). The additive has the ability to improve mixing, aggregate coating, workability, compaction and adhesion with no change in materials or job mix formula required. The study showed that WMA could be successfully placed using conventional HMA paving practices and procedures. Among the different additive dosages used, 0.5% had a better overall performance. The moisture sensitivity tests indicated the highest Tensile Strength Ratio (TSR) at this dosage, suggesting the lowest moisture damage susceptibility. All four mixtures had low rutting resistance potential with no si

FWD testing was completed on three urban arterial sections and six residential streets prior to and after rehabilitation to select the appropriate layout for FWD testing, establish joint performance threshold values, optimize FWD testing time and cost, and evaluate the effect of asphalt overlays on joint performance parameters. Moreover, the performance of full-depth repairs (FDR) and the incorporation of joint performance at the design stage were studied. Residential streets joint and basin FWD testing was completed to evaluate the structural capacity of residential streets and compare their performance to arterial regional roads. Comparisons between two widely used FWD geophones layouts allowed for the selection of a layout that represents the more critical loading condition on joints. Peak deflections and differential deflections were correlated with load transfer efficiencies to select threshold values for LTEs, peak deflections and differential deflections to trigger rehabilitation at the appropriate time. Statistical testing was used to optimize FWD testing to two load levels instead of four. The study found that asphalt overlays reduce recorded deflections and overestimate computed joints performance parameters. The effect of asphalt overlays was evaluated to establish correction factors, Fasphalt, for each load level to estimate deflections on the concrete surface using deflections obtained from testing on the overlay surface of Pembina Highway. The correction was found to improve the reliability of joint condition evaluation for that site. The study also found that FDRs generally restore the load transfer capacity of joints with good support and mechanical load transfer achieved. Moreover, it was demonstrated that joint performance information can be used at the design stage in the decision-making process to select the location and type of joint repairs. Lastly, residential streets were found to have less load transfer capacity than arterial regional roads

Warm Mix Asphalt (WMA) technology has the capability of lowering the temperature at which the asphalt is mixed and compacted by 30°C or more without compromising the performance of asphalt pavement. The reduced difference between asphalt mix and ambient temperature results in a lower cooling rate thus allows for long haul, sufficient compaction time and late season projects compared to the conventional Hot Mix Asphalt (HMA). In northern climate, asphalt paving season is relatively short and paving is often done late in the season when weather conditions are less than ideal. The potential benefit of WMA, among others, is an extended paving season for the City of Winnipeg. Reduction in production temperature also comes with other positive impacts both economically and environmentally. The objective of this study is to evaluate the installation of WMA, compile experiences with this technology and evaluate their effects on construction methods and performance. The study further attempts to evaluate the effectiveness of the WMA chemical additives and its dosage rate as liquid anti-strip agents on the properties of WMA mixtures through field and laboratory testing programs. In addition to the overall effectiveness of WMA, the study aimed to evaluate its economic cost relative to Hot Mix Asphalt (HMA). A chemical additive was used at three different dosages (0.3, 0.5 and 0.7 percent by weight of asphalt cement). The additive has the ability to improve mixing, aggregate coating, workability, compaction and adhesion with no change in materials or job mix formula required. The study showed that WMA could be successfully placed using conventional HMA paving practices and procedures. Among the different additive dosages used, 0.5% had a better overall performance. The moisture sensitivity tests indicated the highest Tensile Strength Ratio (TSR) at this dosage, suggesting the lowest moisture damage susceptibility. All four mixtures had low rutting resistance potential with no si

FWD testing was completed on three urban arterial sections and six residential streets prior to and after rehabilitation to select the appropriate layout for FWD testing, establish joint performance threshold values, optimize FWD testing time and cost, and evaluate the effect of asphalt overlays on joint performance parameters. Moreover, the performance of full-depth repairs (FDR) and the incorporation of joint performance at the design stage were studied. Residential streets joint and basin FWD testing was completed to evaluate the structural capacity of residential streets and compare their performance to arterial regional roads. Comparisons between two widely used FWD geophones layouts allowed for the selection of a layout that represents the more critical loading condition on joints. Peak deflections and differential deflections were correlated with load transfer efficiencies to select threshold values for LTEs, peak deflections and differential deflections to trigger rehabilitation at the appropriate time. Statistical testing was used to optimize FWD testing to two load levels instead of four. The study found that asphalt overlays reduce recorded deflections and overestimate computed joints performance parameters. The effect of asphalt overlays was evaluated to establish correction factors, Fasphalt, for each load level to estimate deflections on the concrete surface using deflections obtained from testing on the overlay surface of Pembina Highway. The correction was found to improve the reliability of joint condition evaluation for that site. The study also found that FDRs generally restore the load transfer capacity of joints with good support and mechanical load transfer achieved. Moreover, it was demonstrated that joint performance information can be used at the design stage in the decision-making process to select the location and type of joint repairs. Lastly, residential streets were found to have less load transfer capacity than arterial regional roads

Photogrammetry conducted with images obtained via Remotely Piloted Aircraft (RPA) has revolutionized the field of land surface monitoring. It is particularly useful where land surface data collection would otherwise be expensive or dangerous. The monitoring of fluvial ice covers can be time-intensive, dangerous, and costly. Fluvial ice roughness is a sensitive parameter in hydraulic models and is difficult to measure using traditional field methods. This research hypothesizes that the surface roughness of a fluvial ice cover is indicative of subsurface roughness. The hypothesis was tested through a comparison of ice roughness determined through inverse hydraulic modeling and ice roughness determined through statistical analysis of ice surfaces derived through RPA-photogrammetry. Hydraulic and topographic data were collected over two years of field research on the Dauphin River in Manitoba, Canada. Various statistical metrics were used to represent the roughness of the surfaces. Strong correlation was identified in the comparison of ice cover roughness determined through RPA-photogrammetry and roughness calculated via the Nezhikhovskiy equation, as well as ice thickness. Some correlation was observed between ice cover roughness observed through RPA-photogrammetry and ice roughness predicted through inverse hydraulic modeling. The inter-quartile range (IQR) was the most representative roughness metric. The maximum peak value performed better in some cases, but this metric would be heavily influenced by outliers, and was rejected as a representative metric. Three distinct forms of surface ice roughness were noted: rough, smooth, and ridged. Statistical properties of elevation data of fluvial ice covers were calculated, none were found to be normally distributed. K-means clustering analysis was used to group cover into two categories, which were interpreted as rough and smooth ice. The IQR of the rough and smooth categories were 0.07 - 0.12 m and 0.01 - 0.05 m, respecti

Warm Mix Asphalt (WMA) technology has the capability of lowering the temperature at which the asphalt is mixed and compacted by 30°C or more without compromising the performance of asphalt pavement. The reduced difference between asphalt mix and ambient temperature results in a lower cooling rate thus allows for long haul, sufficient compaction time and late season projects compared to the conventional Hot Mix Asphalt (HMA). In northern climate, asphalt paving season is relatively short and paving is often done late in the season when weather conditions are less than ideal. The potential benefit of WMA, among others, is an extended paving season for the City of Winnipeg. Reduction in production temperature also comes with other positive impacts both economically and environmentally. The objective of this study is to evaluate the installation of WMA, compile experiences with this technology and evaluate their effects on construction methods and performance. The study further attempts to evaluate the effectiveness of the WMA chemical additives and its dosage rate as liquid anti-strip agents on the properties of WMA mixtures through field and laboratory testing programs. In addition to the overall effectiveness of WMA, the study aimed to evaluate its economic cost relative to Hot Mix Asphalt (HMA). A chemical additive was used at three different dosages (0.3, 0.5 and 0.7 percent by weight of asphalt cement). The additive has the ability to improve mixing, aggregate coating, workability, compaction and adhesion with no change in materials or job mix formula required. The study showed that WMA could be successfully placed using conventional HMA paving practices and procedures. Among the different additive dosages used, 0.5% had a better overall performance. The moisture sensitivity tests indicated the highest Tensile Strength Ratio (TSR) at this dosage, suggesting the lowest moisture damage susceptibility. All four mixtures had low rutting resistance potential with no si

Photogrammetry conducted with images obtained via Remotely Piloted Aircraft (RPA) has revolutionized the field of land surface monitoring. It is particularly useful where land surface data collection would otherwise be expensive or dangerous. The monitoring of fluvial ice covers can be time-intensive, dangerous, and costly. Fluvial ice roughness is a sensitive parameter in hydraulic models and is difficult to measure using traditional field methods. This research hypothesizes that the surface roughness of a fluvial ice cover is indicative of subsurface roughness. The hypothesis was tested through a comparison of ice roughness determined through inverse hydraulic modeling and ice roughness determined through statistical analysis of ice surfaces derived through RPA-photogrammetry. Hydraulic and topographic data were collected over two years of field research on the Dauphin River in Manitoba, Canada. Various statistical metrics were used to represent the roughness of the surfaces. Strong correlation was identified in the comparison of ice cover roughness determined through RPA-photogrammetry and roughness calculated via the Nezhikhovskiy equation, as well as ice thickness. Some correlation was observed between ice cover roughness observed through RPA-photogrammetry and ice roughness predicted through inverse hydraulic modeling. The inter-quartile range (IQR) was the most representative roughness metric. The maximum peak value performed better in some cases, but this metric would be heavily influenced by outliers, and was rejected as a representative metric. Three distinct forms of surface ice roughness were noted: rough, smooth, and ridged. Statistical properties of elevation data of fluvial ice covers were calculated, none were found to be normally distributed. K-means clustering analysis was used to group cover into two categories, which were interpreted as rough and smooth ice. The IQR of the rough and smooth categories were 0.07 - 0.12 m and 0.01 - 0.05 m, respecti

The drainage performance of unbound granular material (UGM) is an important consideration in pavement design because the presence of excess moisture in UGM layers can eventually lead to premature failures. Recently, transportation agencies have been evaluating their granular base and subbase drainage and mechanical performance to ensure sufficient drainage capacity while maintaining adequate structural support to produce more sustainable pavement structures. Linking performance to UGM construction specification requires accurate characterization of UGM’s mechanical and drainage performance and how physical and gradation parameters affect such performance. These evaluations led to an update of the specification requirements of UGM in many jurisdictions including Manitoba. In this research, constant head hydraulic conductivity, resilient modulus, permanent deformation, double ring infiltrometer, and falling weight deflectometer test methods were used in laboratory and field investigations. These tests were conducted to characterize the drainage and mechanical performance of ten UGM samples representing four different gradation bands. The laboratory test results were also used to investigate the reliability of the estimated hydraulic conductivity from the Moulton prediction model and from the Enhanced Integrated Climatic Model (EICM). Test results showed an improvement in resilient modulus and drainage quality for samples in gradation bands that specify larger maximum aggregate size and limited fines. A statistical analysis of the test results showed that D10 larger than 0.2mm and D60 larger than 8mm would guarantee higher stiffness and better drainage performance with a time-to drain of less than 5days for typical pavement cross-sections and a resilient modulus value exceeding 200MPa. The Moulton prediction model was found to provide a better approximation of hydraulic conductivity of the materials included in this study, while the EICM model was found to significantl

This thesis develops a comprehensive understanding of rail profile performance indicators (PIs), their temporal trends and the relation between them. The increasing demand for freight and passenger rail transportation accentuates the need for regular and timely rail maintenance, particularly rail grinding. To enhance the efficiency and effectiveness of maintenance activities, meaningful PIs must be developed and monitored. Despite general recognition of the benefits of adopting performance-based rail monitoring and management programs, knowledge gaps remain in terms of: (1) the selection of relevant indicators of rail condition and performance; (2) deterioration rates and the thresholds that trigger maintenance interventions; and (3) the effectiveness of rail grinding in prolonging the life of rail assets. This research partially fills these knowledge gaps. This research develops a new algorithm in MATLAB© to: (1) automate the extraction, compilation and screening of historical rail profile data, (2) calculate multiple rail profile PIs over multiple years, (3) store the calculation results, and (4) analyse them using qualitative (i.e., temporal trending graphs) and statistical tools (i.e., Spearman correlation technique). The algorithm enables user flexibility in the definition of temporal periods to evaluate performance before and after maintenance interventions. Moreover, it improves analytical efficiency and enables customization of analysis steps and results. The trending and correlation analyses integrate industry-standard PIs (head loss, gauge wear, vertical wear, and grind quality index) with newly-developed PIs (average rail profile, lateral contact position, and contact radius). There appears to be a strong agreement ii between head loss and vertical wear; however, other performance indicators truly measure unique aspects of rail profile performance and should be considered alongside each other. The findings provide some evidence of the value of maintenance

Despite the potential benefits of disability management (DM) programs with respect to reducing costs and improving workplace morale, many organizations in the construction industry appear unable to develop and implement them. Inadequate support and practices at the organizational level affect the degree to which construction workplaces can accommodate disabled employees returning to the workplace with a disability, reinforcing the need to investigate the maturity of related practices. This research aimed to investigate disability management in the Manitoban construction industry and its relation to safety performance. The research developed the Construction Disability Management Maturity Model, which benchmarks construction companies’ disability management performance using 12 indicators. The weights of importance of these indicators was determined by eight experts using an analytical hierarchy process. The model was then applied to a sample of 10 general contractors in Manitoba using an assessment worksheet. The research also involved adopting three safety metrics and developing 12 new DM metrics and using them to evaluate the safety and DM performance of the same general contracting companies. The maturity model results were correlated to the disability management and safety performance metric results to investigate the relationship between construction organizations’ DM maturity and their DM and safety performance. The analytical hierarchy process showed “Return to work and accommodation” and “Disability and injury management” practices were the most critical indicators whereas “Physical accessibility management” and “Claims management” practices were the least critical. The results also showed after applying the CDM3 that the ten construction companies operated at the quantitatively managed level. “Senior management support” and “Disability and injury prevention” were found to be the most mature indicators whereas “Retention and recruitment” and “Communication”

Measuring the quality of as-built Asphalt Concrete (AC) mixtures provide useful information about the current and long-term performance of pavements. By the advent of the mechanistic-empirical pavement design method, the dynamic modulus has become one of the primary performance indicators required for characterizing the performance of AC mixtures. The dynamic modulus is commonly measured using cylindrical specimens having a 100 mm diameter and a 150 mm height (full-size specimens). Testing as-built AC mixtures using this geometry is rarely possible because the required specimen height is greater than the typical AC lift thickness. In this study, the feasibility of using small-scale cylindrical specimens to measure the dynamic modulus of AC mixtures was investigated. Initially, the specimens were prepared in the laboratory using loose mixtures obtained from the field. Dynamic modulus test was conducted on full-size and two small-scale (common height of 110 mm and two diameters of 38 and 50 mm) geometries extracted from gyratory compacted samples. A uniaxial hydraulic loading frame was used to test specimens at the standard temperatures and frequencies. Both small geometries showed similar performances to full-size specimens except at high temperature of 37.8°C, where they resulted in greater dynamic modulus values compared to full-size geometry. The coefficient of variation for 38mm-diameter specimens was found to be higher than two other geometries. Secondly, field cores were collected from highways to characterize as-built AC mixtures using three tests, including dynamic modulus, Hamburg Wheel-Tracking (HWT), and ignition oven. Ignition oven test was performed on field cores to mainly control the aggregate gradation of mixtures. For the dynamic modulus test, small-scale specimens were extracted from field cores, and stiffness values at 37.8°C were corrected using calibration factors obtained from the initial phase. For the HWT test, the heights of field cores were

The drainage performance of unbound granular material (UGM) is an important consideration in pavement design because the presence of excess moisture in UGM layers can eventually lead to premature failures. Recently, transportation agencies have been evaluating their granular base and subbase drainage and mechanical performance to ensure sufficient drainage capacity while maintaining adequate structural support to produce more sustainable pavement structures. Linking performance to UGM construction specification requires accurate characterization of UGM’s mechanical and drainage performance and how physical and gradation parameters affect such performance. These evaluations led to an update of the specification requirements of UGM in many jurisdictions including Manitoba. In this research, constant head hydraulic conductivity, resilient modulus, permanent deformation, double ring infiltrometer, and falling weight deflectometer test methods were used in laboratory and field investigations. These tests were conducted to characterize the drainage and mechanical performance of ten UGM samples representing four different gradation bands. The laboratory test results were also used to investigate the reliability of the estimated hydraulic conductivity from the Moulton prediction model and from the Enhanced Integrated Climatic Model (EICM). Test results showed an improvement in resilient modulus and drainage quality for samples in gradation bands that specify larger maximum aggregate size and limited fines. A statistical analysis of the test results showed that D10 larger than 0.2mm and D60 larger than 8mm would guarantee higher stiffness and better drainage performance with a time-to drain of less than 5days for typical pavement cross-sections and a resilient modulus value exceeding 200MPa. The Moulton prediction model was found to provide a better approximation of hydraulic conductivity of the materials included in this study, while the EICM model was found to significantl

Comprehensive elastoacoustics investigation of submerged and buried shell structures is the main objective. Analyses are carried out in frequency and time domains under a generalized loading condition and various material configurations for different constitutive rules. Major part of this study is performed analytically within the linear domain. The last chapter on cubature formulae, however, is a prelude to numerical analysis when nonlinearities of various types are introduced into the problem. Primarily, an exhaustive comparative study is carried out on the performance of the most popular shell theories in elastoacoustics modelling shell structures subjected to a transient excitation. These models approximate the exact local theory of linear elasticity. Consequently, a discontinuation in their application, under a general nonstationary excitation, is strongly recommended, henceforth. Subsequently the total responses are considered when a centrally symmetric excitation is applied. The corresponding numerical experiments convey practically significant implications. A more general situation for a buried shell structure, rather than a fluid submerged case, is considered next. The exact local theory of linear elasticity is applied to the both of elastic media whilst the linear acoustical theory for compressible fluids is utilized. Both of generalized traction forces and waves being incident upon a shell's either surfaces are considered as the excitation’s sources. Incident waves of shear and compressional nature are included. Origins of these sources are located within the encompassing elastic medium, shell's material or the contained fluid. Extensive sets of numerical examples are performed by using special visualization techniques after which different limiting situations are studied. A generalized Hook's law along with piezoelasticity for anisotropic materials, on the other hand, is considered subsequently for the shells submerged in an acoustical wedge medium rathe

Measuring the quality of as-built Asphalt Concrete (AC) mixtures provide useful information about the current and long-term performance of pavements. By the advent of the mechanistic-empirical pavement design method, the dynamic modulus has become one of the primary performance indicators required for characterizing the performance of AC mixtures. The dynamic modulus is commonly measured using cylindrical specimens having a 100 mm diameter and a 150 mm height (full-size specimens). Testing as-built AC mixtures using this geometry is rarely possible because the required specimen height is greater than the typical AC lift thickness. In this study, the feasibility of using small-scale cylindrical specimens to measure the dynamic modulus of AC mixtures was investigated. Initially, the specimens were prepared in the laboratory using loose mixtures obtained from the field. Dynamic modulus test was conducted on full-size and two small-scale (common height of 110 mm and two diameters of 38 and 50 mm) geometries extracted from gyratory compacted samples. A uniaxial hydraulic loading frame was used to test specimens at the standard temperatures and frequencies. Both small geometries showed similar performances to full-size specimens except at high temperature of 37.8°C, where they resulted in greater dynamic modulus values compared to full-size geometry. The coefficient of variation for 38mm-diameter specimens was found to be higher than two other geometries. Secondly, field cores were collected from highways to characterize as-built AC mixtures using three tests, including dynamic modulus, Hamburg Wheel-Tracking (HWT), and ignition oven. Ignition oven test was performed on field cores to mainly control the aggregate gradation of mixtures. For the dynamic modulus test, small-scale specimens were extracted from field cores, and stiffness values at 37.8°C were corrected using calibration factors obtained from the initial phase. For the HWT test, the heights of field cores were

The drainage performance of unbound granular material (UGM) is an important consideration in pavement design because the presence of excess moisture in UGM layers can eventually lead to premature failures. Recently, transportation agencies have been evaluating their granular base and subbase drainage and mechanical performance to ensure sufficient drainage capacity while maintaining adequate structural support to produce more sustainable pavement structures. Linking performance to UGM construction specification requires accurate characterization of UGM’s mechanical and drainage performance and how physical and gradation parameters affect such performance. These evaluations led to an update of the specification requirements of UGM in many jurisdictions including Manitoba. In this research, constant head hydraulic conductivity, resilient modulus, permanent deformation, double ring infiltrometer, and falling weight deflectometer test methods were used in laboratory and field investigations. These tests were conducted to characterize the drainage and mechanical performance of ten UGM samples representing four different gradation bands. The laboratory test results were also used to investigate the reliability of the estimated hydraulic conductivity from the Moulton prediction model and from the Enhanced Integrated Climatic Model (EICM). Test results showed an improvement in resilient modulus and drainage quality for samples in gradation bands that specify larger maximum aggregate size and limited fines. A statistical analysis of the test results showed that D10 larger than 0.2mm and D60 larger than 8mm would guarantee higher stiffness and better drainage performance with a time-to drain of less than 5days for typical pavement cross-sections and a resilient modulus value exceeding 200MPa. The Moulton prediction model was found to provide a better approximation of hydraulic conductivity of the materials included in this study, while the EICM model was found to significantl

This thesis develops a comprehensive understanding of rail profile performance indicators (PIs), their temporal trends and the relation between them. The increasing demand for freight and passenger rail transportation accentuates the need for regular and timely rail maintenance, particularly rail grinding. To enhance the efficiency and effectiveness of maintenance activities, meaningful PIs must be developed and monitored. Despite general recognition of the benefits of adopting performance-based rail monitoring and management programs, knowledge gaps remain in terms of: (1) the selection of relevant indicators of rail condition and performance; (2) deterioration rates and the thresholds that trigger maintenance interventions; and (3) the effectiveness of rail grinding in prolonging the life of rail assets. This research partially fills these knowledge gaps. This research develops a new algorithm in MATLAB© to: (1) automate the extraction, compilation and screening of historical rail profile data, (2) calculate multiple rail profile PIs over multiple years, (3) store the calculation results, and (4) analyse them using qualitative (i.e., temporal trending graphs) and statistical tools (i.e., Spearman correlation technique). The algorithm enables user flexibility in the definition of temporal periods to evaluate performance before and after maintenance interventions. Moreover, it improves analytical efficiency and enables customization of analysis steps and results. The trending and correlation analyses integrate industry-standard PIs (head loss, gauge wear, vertical wear, and grind quality index) with newly-developed PIs (average rail profile, lateral contact position, and contact radius). There appears to be a strong agreement ii between head loss and vertical wear; however, other performance indicators truly measure unique aspects of rail profile performance and should be considered alongside each other. The findings provide some evidence of the value of maintenance

Despite the potential benefits of disability management (DM) programs with respect to reducing costs and improving workplace morale, many organizations in the construction industry appear unable to develop and implement them. Inadequate support and practices at the organizational level affect the degree to which construction workplaces can accommodate disabled employees returning to the workplace with a disability, reinforcing the need to investigate the maturity of related practices. This research aimed to investigate disability management in the Manitoban construction industry and its relation to safety performance. The research developed the Construction Disability Management Maturity Model, which benchmarks construction companies’ disability management performance using 12 indicators. The weights of importance of these indicators was determined by eight experts using an analytical hierarchy process. The model was then applied to a sample of 10 general contractors in Manitoba using an assessment worksheet. The research also involved adopting three safety metrics and developing 12 new DM metrics and using them to evaluate the safety and DM performance of the same general contracting companies. The maturity model results were correlated to the disability management and safety performance metric results to investigate the relationship between construction organizations’ DM maturity and their DM and safety performance. The analytical hierarchy process showed “Return to work and accommodation” and “Disability and injury management” practices were the most critical indicators whereas “Physical accessibility management” and “Claims management” practices were the least critical. The results also showed after applying the CDM3 that the ten construction companies operated at the quantitatively managed level. “Senior management support” and “Disability and injury prevention” were found to be the most mature indicators whereas “Retention and recruitment” and “Communication”

Measuring the quality of as-built Asphalt Concrete (AC) mixtures provide useful information about the current and long-term performance of pavements. By the advent of the mechanistic-empirical pavement design method, the dynamic modulus has become one of the primary performance indicators required for characterizing the performance of AC mixtures. The dynamic modulus is commonly measured using cylindrical specimens having a 100 mm diameter and a 150 mm height (full-size specimens). Testing as-built AC mixtures using this geometry is rarely possible because the required specimen height is greater than the typical AC lift thickness. In this study, the feasibility of using small-scale cylindrical specimens to measure the dynamic modulus of AC mixtures was investigated. Initially, the specimens were prepared in the laboratory using loose mixtures obtained from the field. Dynamic modulus test was conducted on full-size and two small-scale (common height of 110 mm and two diameters of 38 and 50 mm) geometries extracted from gyratory compacted samples. A uniaxial hydraulic loading frame was used to test specimens at the standard temperatures and frequencies. Both small geometries showed similar performances to full-size specimens except at high temperature of 37.8°C, where they resulted in greater dynamic modulus values compared to full-size geometry. The coefficient of variation for 38mm-diameter specimens was found to be higher than two other geometries. Secondly, field cores were collected from highways to characterize as-built AC mixtures using three tests, including dynamic modulus, Hamburg Wheel-Tracking (HWT), and ignition oven. Ignition oven test was performed on field cores to mainly control the aggregate gradation of mixtures. For the dynamic modulus test, small-scale specimens were extracted from field cores, and stiffness values at 37.8°C were corrected using calibration factors obtained from the initial phase. For the HWT test, the heights of field cores were

The drainage performance of unbound granular material (UGM) is an important consideration in pavement design because the presence of excess moisture in UGM layers can eventually lead to premature failures. Recently, transportation agencies have been evaluating their granular base and subbase drainage and mechanical performance to ensure sufficient drainage capacity while maintaining adequate structural support to produce more sustainable pavement structures. Linking performance to UGM construction specification requires accurate characterization of UGM’s mechanical and drainage performance and how physical and gradation parameters affect such performance. These evaluations led to an update of the specification requirements of UGM in many jurisdictions including Manitoba. In this research, constant head hydraulic conductivity, resilient modulus, permanent deformation, double ring infiltrometer, and falling weight deflectometer test methods were used in laboratory and field investigations. These tests were conducted to characterize the drainage and mechanical performance of ten UGM samples representing four different gradation bands. The laboratory test results were also used to investigate the reliability of the estimated hydraulic conductivity from the Moulton prediction model and from the Enhanced Integrated Climatic Model (EICM). Test results showed an improvement in resilient modulus and drainage quality for samples in gradation bands that specify larger maximum aggregate size and limited fines. A statistical analysis of the test results showed that D10 larger than 0.2mm and D60 larger than 8mm would guarantee higher stiffness and better drainage performance with a time-to drain of less than 5days for typical pavement cross-sections and a resilient modulus value exceeding 200MPa. The Moulton prediction model was found to provide a better approximation of hydraulic conductivity of the materials included in this study, while the EICM model was found to significantl

Measuring the quality of as-built Asphalt Concrete (AC) mixtures provide useful information about the current and long-term performance of pavements. By the advent of the mechanistic-empirical pavement design method, the dynamic modulus has become one of the primary performance indicators required for characterizing the performance of AC mixtures. The dynamic modulus is commonly measured using cylindrical specimens having a 100 mm diameter and a 150 mm height (full-size specimens). Testing as-built AC mixtures using this geometry is rarely possible because the required specimen height is greater than the typical AC lift thickness. In this study, the feasibility of using small-scale cylindrical specimens to measure the dynamic modulus of AC mixtures was investigated. Initially, the specimens were prepared in the laboratory using loose mixtures obtained from the field. Dynamic modulus test was conducted on full-size and two small-scale (common height of 110 mm and two diameters of 38 and 50 mm) geometries extracted from gyratory compacted samples. A uniaxial hydraulic loading frame was used to test specimens at the standard temperatures and frequencies. Both small geometries showed similar performances to full-size specimens except at high temperature of 37.8°C, where they resulted in greater dynamic modulus values compared to full-size geometry. The coefficient of variation for 38mm-diameter specimens was found to be higher than two other geometries. Secondly, field cores were collected from highways to characterize as-built AC mixtures using three tests, including dynamic modulus, Hamburg Wheel-Tracking (HWT), and ignition oven. Ignition oven test was performed on field cores to mainly control the aggregate gradation of mixtures. For the dynamic modulus test, small-scale specimens were extracted from field cores, and stiffness values at 37.8°C were corrected using calibration factors obtained from the initial phase. For the HWT test, the heights of field cores were

Roadways over culverts experience severe roughness due to the differential frost heave and thaw settlement in cold regions. Five instrumented culvert sites with different designs to mitigate road roughness were constructed and monitored for two years in Manitoba, Canada. The sites were different in the culvert diameter, type of backfill material, depth of cover, geosynthetics, and thermal insulation. The objectives of the study was to provide design of culverts in cold regions to mitigate road roughness, and develop a numerical model for geotechnical engineering applications in cold regions. A 2-D thermal numerical model was established, validated, and applied on geotechnical engineering applications in cold regions. The study concluded that thermal insulation and geosynthetics had noticeable effect on mitigating road roughness over culverts, and different placements of thermal insulation at the vicinity of culverts could be used to reduce the severity of several geotechnical problems in cold regions.

Transportation agencies seek to optimize their public budget to finance the construction and maintenance of pavements. Life Cycle Cost Analysis (LCCA) is a decision support tool that allows agencies to contrast and optimize infrastructure design alternatives based on the costs of the asset over its lifetime. In this thesis, statistical distributions were developed to study the variability associated with LCCA inputs based on agency historical data of the Province of Manitoba and the City of Winnipeg. A case study was used to compare the deterministic and the probabilistic computational approaches results. The results demonstrated that a probabilistic LCCA provides reliability levels for the evaluation of the total project cost, which allows for analyzing the risk associated with each alternative and avoiding cost overruns. It is recommended that transportation agencies consider probabilistic LCCA as part of their decision-making process due to the economic benefits and reliability levels that this approach provides.

The Mechanistic Empirical Pavement Design Guide (MEPDG) method, currently known as Pavement ME, recommends using locally calibrated material characterization models developed from laboratory testing of local materials under specific environmental and traffic loading conditions. The Pavement ME design method offers a more realistic design procedure and reduces the uncertainty that arise from empirical design procedures. This thesis developed a locally calibrated indirect tensile (IDT) strength material model for low temperature cracking predictions of hot mix asphalt (HMA) in Manitoba, Canada. In addition, the research investigated the integration of locally calibrated HMA, and unbound granular material characterization models into the Pavement ME framework to improve the design of flexible pavements. Laboratory IDT testing was conducted on typical HMA mixtures containing extracted binders and varying percentages of reclaimed asphalt pavement (RAP). The laboratory measured IDT strengths were used to calibrate a local IDT strength predictive model for Manitoba. The predictions from the local Manitoba model were compared to the predictions from the global Pavement ME IDT model, and a Michigan calibrated IDT model, using a statistical analysis. It was found that the global Pavement ME IDT strength model, if used without local calibration, produced inaccurate predictions of the IDT strength for Manitoba mixtures. It was also found that binder characterization methods in Level 2 and Level 3 can significantly impact the accuracy of IDT strength predictions. A case study using developed local HMA, base, and subgrade material characterization models in Manitoba were compared to designs using default (Level 3) material input values in Pavement ME design software. The results of integrating the locally calibrated models for HMA, base and subgrade layers demonstrated that the locally calibrated materials model inputs produce lower pavement structural thicknesses with higher rel

The objective of this thesis is to apply thermal analysis, coupled thermo-hydraulic analysis, and fully coupled thermo-hydro-mechanical analysis developed in this research to different engineering designs in cold regions. The applications vary from Geothermal Snow-Melting System Design to Structural and Thermal Integrity of Buried Infrastructure in cold regions. A feasibility study of geothermal energy pile based snow melting systemwas performed for six major cities in Canada. The coefficient of performance (COP) of heat pump is derived and the number of geothermal piles are determined for each city based on its specific local geological condition and heating demand.Also, the structural and thermal integrity of buried infrastructure were studied by performing an optimum design of rigid plastic foam insulations to protect buried utilities against frost damage and reduce the excavation cost. Furthermore, the effect of frost heave on the structural integrity of pavement structure and culverts are assessed.

The Mechanistic Empirical Pavement Design Guide (MEPDG) method, currently known as Pavement ME, recommends using locally calibrated material characterization models developed from laboratory testing of local materials under specific environmental and traffic loading conditions. The Pavement ME design method offers a more realistic design procedure and reduces the uncertainty that arise from empirical design procedures. This thesis developed a locally calibrated indirect tensile (IDT) strength material model for low temperature cracking predictions of hot mix asphalt (HMA) in Manitoba, Canada. In addition, the research investigated the integration of locally calibrated HMA, and unbound granular material characterization models into the Pavement ME framework to improve the design of flexible pavements. Laboratory IDT testing was conducted on typical HMA mixtures containing extracted binders and varying percentages of reclaimed asphalt pavement (RAP). The laboratory measured IDT strengths were used to calibrate a local IDT strength predictive model for Manitoba. The predictions from the local Manitoba model were compared to the predictions from the global Pavement ME IDT model, and a Michigan calibrated IDT model, using a statistical analysis. It was found that the global Pavement ME IDT strength model, if used without local calibration, produced inaccurate predictions of the IDT strength for Manitoba mixtures. It was also found that binder characterization methods in Level 2 and Level 3 can significantly impact the accuracy of IDT strength predictions. A case study using developed local HMA, base, and subgrade material characterization models in Manitoba were compared to designs using default (Level 3) material input values in Pavement ME design software. The results of integrating the locally calibrated models for HMA, base and subgrade layers demonstrated that the locally calibrated materials model inputs produce lower pavement structural thicknesses with higher rel

Transportation agencies seek to optimize their public budget to finance the construction and maintenance of pavements. Life Cycle Cost Analysis (LCCA) is a decision support tool that allows agencies to contrast and optimize infrastructure design alternatives based on the costs of the asset over its lifetime. In this thesis, statistical distributions were developed to study the variability associated with LCCA inputs based on agency historical data of the Province of Manitoba and the City of Winnipeg. A case study was used to compare the deterministic and the probabilistic computational approaches results. The results demonstrated that a probabilistic LCCA provides reliability levels for the evaluation of the total project cost, which allows for analyzing the risk associated with each alternative and avoiding cost overruns. It is recommended that transportation agencies consider probabilistic LCCA as part of their decision-making process due to the economic benefits and reliability levels that this approach provides.

Roadways over culverts experience severe roughness due to the differential frost heave and thaw settlement in cold regions. Five instrumented culvert sites with different designs to mitigate road roughness were constructed and monitored for two years in Manitoba, Canada. The sites were different in the culvert diameter, type of backfill material, depth of cover, geosynthetics, and thermal insulation. The objectives of the study was to provide design of culverts in cold regions to mitigate road roughness, and develop a numerical model for geotechnical engineering applications in cold regions. A 2-D thermal numerical model was established, validated, and applied on geotechnical engineering applications in cold regions. The study concluded that thermal insulation and geosynthetics had noticeable effect on mitigating road roughness over culverts, and different placements of thermal insulation at the vicinity of culverts could be used to reduce the severity of several geotechnical problems in cold regions.

The objective of this thesis is to apply thermal analysis, coupled thermo-hydraulic analysis, and fully coupled thermo-hydro-mechanical analysis developed in this research to different engineering designs in cold regions. The applications vary from Geothermal Snow-Melting System Design to Structural and Thermal Integrity of Buried Infrastructure in cold regions. A feasibility study of geothermal energy pile based snow melting systemwas performed for six major cities in Canada. The coefficient of performance (COP) of heat pump is derived and the number of geothermal piles are determined for each city based on its specific local geological condition and heating demand.Also, the structural and thermal integrity of buried infrastructure were studied by performing an optimum design of rigid plastic foam insulations to protect buried utilities against frost damage and reduce the excavation cost. Furthermore, the effect of frost heave on the structural integrity of pavement structure and culverts are assessed.