Civil Engineering

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https://hdl.handle.net/10315/34418

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Open Access
A Data-Driven Systematic Approach to Identify, Classify, and Estimate Long-Haul Freight Truck Parking Supply
(2020-08-11) Nevland, Erik Alexander; Park, Peter; Gingerich, Kevin
Collisions involving trucks have increased fatality risks compared to passenger vehicles. Hours-of-Service (HOS) laws exist to reduce fatalities where truck driver fatigue is a contributing factor. Electronic logging devices (ELD) are being mandated to automatically track HOS and enforce compliance, creating a greater urgency for adequate truck parking. A lack of truck parking is often identified throughout North America; however, these studies are often limited to public rest areas despite evidence that drivers often utilize other types of parking. To adequately compare truck parking supply and demand, an exhaustive truck parking classification scheme is developed based on important location attributes identified through extensive literature review. This scheme can be systematically implemented using available geospatial data. This data is then used to develop a truck parking supply model based on a negative binomial regression. The Region of Peel is used as the study area due to its considerably large freight industry.
Open Access
A GIS-Based LID Framework for Sustainable Urban Runoff Management
(2021-11-15) Kaykhosravi, Sarah; Khan, Usman T.; Jadidi, Mojgan
Low Impact Development (LID) is one of the most popular sustainable techniques for runoff reduction in urban areas. LID mimics nature by retaining or detaining the runoff at the source. Examples of LID include bioretention cells, green roofs, and porous pavements. While the primary purpose of LID is runoff reduction, several lateral benefits (environmental and socioeconomic) are accrued from LID. Even though many studies have shown the effectiveness of LID on runoff reduction, investigation around many other aspects of LID has remained limited. Out of all these aspects, there is a significant lack of a systematic decision-making model to rank LID solutions (suggest where to implement LID and what type of LID to use) to maximize the LID benefits. The objective of this dissertation is to develop an innovative simplified geospatial model (referred to as LID-Solution Evaluation and Ranking ApproacH (SERAH)) to rank the LID solutions. SERAH develops a Hydrological-Hydraulic Index (HHI) and integrates it into a Multi Criteria Decision Making (MCDM) model considering the key criteria contributing to the ranking LID solutions. In this research, the application and effectiveness of SERAH and its corresponding indices were examined under various case scenarios and case studies (e.g., City of Toronto as the study site). Also, SERAH was validated against physical models such as HEC-HMS and PCSWMM. Further, the HHI was used for modelling climate change and urbanization scenarios for three Canadian metropolitans (Toronto, Montreal, and Vancouver). The results of this study show that, unlike the traditional methods which use stormwater modeling for ranking LID solutions, SERAH effectively ranks LID solutions using geospatial analysis. SERAH and its corresponding indices are universally applicable since they have been deductively developed and like many similar methods are not induced and custom-built around a sample dataset. The results of this research lend themselves to the strategic planning of multifunctional sustainable infrastructures (LID); give a holistic insight about current and future demands for LID; integrate multiple disciplines (socioeconomic, environmental, geography, and hydrology) to find comprehensive sustainable solutions; and suggest a future need for similar multidisciplinary research by highlighting the gaps and limitations.
Open Access
A Holistic Approach to Mass Timber Design
(2023-12-08) Philion, Ethan Paul; Gales, John A.
As a new material, there is a significant lack of knowledge of the performance of mass timber, especially in fire. This research investigated the current understanding of modern mass timber, the performance of heritage mass timber, and the state of diversity of the industry itself. Findings include heritage hardwoods typically charred at a higher rate than the heritage softwoods but the species converged at a rate of 1.05 mm/min when exposed to 50 kW/m². Gender distributions of the survey (16% women, 81.7% men) mirrored industry statistics. It was also found that 71.4% of the women were ages 44 and under compared to 39.1% for men. The findings of this thesis can be used to further the design of mass timber structures and direct where future research for mass timber is needed most.
Open Access
A Swept Path Analysis of Intersection Designs for Long Combination Vehicles
(2022-08-08) Saha, Ucchas; Gingerich, Kevin
The efficiency of a supply chain depends heavily on a region's ability to accommodate trucks of varying sizes. Intersections are potential bottleneck locations for first- and last-mile logistics, where complexities arise due to inadequate geometric properties. The superior productivity of Long Combination Vehicles (LCVs) has led to increasing adoption by large establishments. However, LCVs face significant impediments due to their extra lengths and subsequent impacts on turning envelopes. This thesis focuses on the range and combination of geometric factors leading to successful LCV right-turn movements, such as curb radii and lane widths. Swept-path simulations are conducted for seven intersections in the Region of Peel using AutoTURN software to classify scenarios as pass or fail. Binomial logit models are estimated from these results. The correct prediction rates of the models range from 74% to 97%. A quick-response toolkit is developed to assist roadway authorities in the LCV route acceptance process.
Open Access
Alternative Solutions for Canadian Fire Engineering Design
(2021-11-15) Jeanneret, Chloe Valerie; Gales, John A.
Fire Safety Engineering is important for resilient infrastructure design. Canadian structural fire design is currently restricted by its reliance upon prescriptive approaches. This research is the first step in the development of generalized frameworks from which practitioners can create Canadian alternative solutions. A methodology to develop an acceptance criterion for the fire design of unbonded post-tensioned concrete slabs is outlined. A stress relaxation model was used to establish preliminary definitions of critical design thermal boundaries. The analysis illustrated the need to consider travelling and localised design fires due to the vulnerability of unbonded tendons to localized heating. The fire performance of steel beam-to-column connections was then considered experimentally. This research program was the first step that will lead to the generation of analytical tools and further guidance regarding steel connections in fire. The results of the study provided preliminary guidance towards updating Annex K within CSA S16-19.
Open Access
An analysis of 100 years of post-fire streamflow responses of British Columbia watersheds
(2024-03-16) Abogadil, Karen Elaine; Khan, Usman T.
Wildfires are becoming larger and more severe due to climate change. This trend is destructive to the forest ecosystem, disrupting many eco-hydrologic processes in forested watersheds. Effects can include rapid runoff responses, increased surface runoff, and elevated erosion, leading to lower water quality and long-lasting effects on hydrologic ecosystem services (such as flood regulation). However, post-fire hydrology studies often have variable and contrasting results, making cross-study comparisons difficult. Studies are typically short-term and focused on single wildfire events. This research aims to determine accurate indicators for post-fire flow responses. The study area includes 257 drainage basins (grouped into five ecozones) in British Columbia, Canada, known for its susceptibility to wildfires and floods. The study analyzes wildfire data from 1910 to 2020. Post-fire percent changes for four hydrological metrics (low, high, peak flows and runoff ratio) were calculated using pre-fire and post-fire values for multiple temporal bands. Using streamflow, precipitation, temperature, wildfire perimeters, and topographic data, statistical analyses including hypothesis testing and multiple linear regression were done. The two-sample Kolmogorov-Smirnov test results comparing the fire group against the two control groups resulted in highly variable p-values. Multiple linear regression was done to predict the percent changes for all flows. Regression yielded poor model performance, suggesting that the hydrometeorological parameters alone cannot explain the post-fire changes observed. The most frequently influential watershed indicators in post-fire streamflow responses were percent burn, maximum daily temperature, and elevation. Results across multiple temporal bands, ecozones and hydrological metrics over 100 years will aid future research on the wildfire effects on hydrology in forested watersheds.
Open Access
Analysis of Different Design Approaches to Favor the Growth of Polyhydroxybutyrate (PHB) Producers in a Methane Utilizing Mixed Culture Community
(2020-11-13) Salem, Rana Khaled Moselhy Ahmed; Audette, Gerald F.; Eldyasti, Ahmed
Currently, petroleum-based plastic disposal and its subsequent accumulation in the environment have become a major concern in recent years. Hence, the industrialization of bioplastics, PHA biopolymer has gained broad interest in recent years. This thesis offers an efficient approach for maximizing PHB polymer production in methanotrophic bacteria through using the methane gas produced in the anaerobic digestion process in wastewater treatment plants (WWTPs). This is achieved through offering an innovative selection approach for PHB producers including type II methanotrophs whilst enabling other PHB accumulators to grow simultaneously. PHB accumulation reached around 60% accumulation in ammonia mineral salt (AMS) media and 55% in nitrate mineral salt (NMS), which is higher than what has been reached in the literature for both nitrogen sources. Furthermore, characterization of the PHB polymer with Sudan Black B dye and NMR. Lastly, an optimization of the operational parameters; using central composite design (CCD) have been performed.
Open Access
Analysis of Drinking Water Distribution Systems using the Engineering Design Process
(2024-03-16) Moghaddam-Ghadimi, Sara; Gora, Stephanie
Our research has identified that issues pertaining to distribution infrastructure are a leading cause of water safety vulnerability. These challenges are exacerbated within small communities which experience a disproportionate number of boil water advisories compared to larger communities. This study used the engineering design process to explore the root causes and potential solutions to water safety hazards within the water distribution system. A systematic literature review thoroughly examined data-backed evidence of issues causing potential threats to drinking water safety. Potential solutions involving the implementation of distributed treatment using UV LEDs installed at different points in the distribution system were identified through research and stakeholder consultation and compared to one another using EPANET software. The results of this analysis indicated that installing UV LEDs at the point-of-entry could potentially be used to reduce the impact of water safety hazards within the distribution system.
Open Access
Analysis of unsaturated hydraulic properties for low impact developments and their performance under changing climate
(2021-07-06) Guram, Satbir; Bashir, Rashid
Climate change has resulted in an increase in both intensity and frequency of extreme rainfall events leading to a higher probability of flooding. To counter the impacts of climate change and urbanization, engineers have developed ingenious solutions to reduce flooding through the use of Low Impact Developments (LIDs). The soil is generally considered to be completely saturated when designing for the LIDs. However, this may not always be an accurate or realistic approach, as the soil could be variably unsaturated leading to inaccurate designs. Laboratory and field measurements of unsaturated hydraulic properties are cumbersome, expensive and time-consuming. An alternative approach is to estimate unsaturated hydraulic properties using pedotransfer functions (PTFs). This first part of this research presents a comparison between the direct measurement obtained through experimental procedures and the use of PTFs to estimate soil hydraulic properties for green roof and bioretention soil medias. Comparison between the measured and estimated soil hydraulic properties was accomplished using two different approaches. Statistical analyses and visual comparisons were used to compare the measured and estimated soil hydraulic properties. Additionally, numerical modeling to predict the water balance at the ground surface was conducted using the measured and estimated soil hydraulic properties. Results indicate that there is a high level of uncertainty when using PTFs for LID materials. It is ideal to analyze existing and future LID systems within the context of changing climate. Thus, the second part of this research will assist in the determination of whether the LID system design objectives can be met within the context of changing climate. In order to conduct this analysis, numerical modelling was completed. Material properties previously measured in the laboratory for bioretention and green roof substrates were used in the numerical modeling. Long-term and short-term climate data for ten locations in Ontario was used in this examination. The results of this research suggest that LID performance may decrease due to the increased quantity of water projected in the future due to climate change. Results indicate that the percent change in future long-term maximum infiltration values for green roofs can be as much as 100%, whereas for bioretention facilities it can be in the order of 50%. Moreover, a general decrease in both the peak reduction and peak time delay for the green roof facilities can be expected for the future. Some 100-year storms in Ontario can see as much as 50 cm increase in untreated stormwater run-off from bioretention facilities.
Open Access
Artificial Intelligence-Based Prediction of Permeable Pavement Surface Infiltration Rates
(2022-03-03) Malik, Arham; Khan, Usman; Butler, Liam
Permeable pavements are a type of low impact development technology that is an alternative to conventional asphalt pavements. These pavements are used to address urban stormwater runoff concerns through infiltration and storage. Overtime, sediments carried by stormwater runoff degrade the performance of these pavements and can eventually diminish the infiltration capacity to the point where no infiltration takes place. The objective of this research is to develop a data-driven model to predict the infiltration rate of permeable pavements. Four permeable concrete lab specimens were constructed and subjected to clogging cycles while obtaining surface images and infiltration data. An artificial neural network was created to investigate the relationship between the images of the pavement surface and its associated surface infiltration rate. Results indicated that image parameters do change significantly as pavements clog and are suitable as inputs to predict surface infiltration rate, although model variability needs to be addressed.
Open Access
Artificial Neural Network-Based Flood Forecasting: Input Variable Selection and Peak Flow Prediction Accuracy
(2019-11-22) Snieder, Everett Joshua; Khan, Usman
Floods are the most frequent and costly natural disaster in Canada. Flow forecasting models can be used to provide an advance warning of flood risk and mitigate flood damage. Data-driven models have proven to be suitable for flow forecasting applications, yet there are several outstanding challenges associated with model development. Firstly, this research compares four methods for input variable selection for data-driven models, which are used to minimize model complexity and improve performance. Next, methods for reducing the temporal error for data-driven flood forecasting models are investigated. Two procedures are proposed to minimize timing error: error weighting and least-squares boosting. A class of performance measures called visual measures is used to discriminate between timing and amplitude errors, and hence quantifying the impacts of each correction procedure. These studies showcase methods for improving the performance of flow forecasting models, more reliable flood risk predictions, and better preparedness for flood events.
Open Access
Assessment of Sidestream And Mainstream Anammox-Based Systems Using Experimental and Mathematical Modelling Tools
(2021-11-15) Izadi, Parin; Eldyasti, Ahmed K.
Anaerobic Ammonium Oxidation (ANAMMOX) process is an innovative alternative which is carried out by an entirely autotrophic method for shortcut N-removal in nitrogen cycle, in addition this technological advancement results in less aeration demand, decline in organic matter addition as well as nitrite reduction. Compared to conventional biological nitrogen removal processes, an ANAMMOX-based process can potentially save energy since it reduces oxygen requirement by around 60%, organic carbon utilization by 100%, and sludge production by approximately 90%. Due to low growth rates and cellular yields of autotrophic ammonia removal bacterial communities and their sensitivity to adverse environmental conditions, ANAMMOX reactor startup from conventional returned activated sludge has become a major challenge. This comprehensive study aimed to understand the engineering aspects and practical applications of ANAMMOX-based autotrophic nitrogen removal processes and overcome the current challenges. Fast start-up using micro-granular development of ANAMMOX reactor was investigated to evaluate ANAMMOX activity, population dynamics and core community members as well as the potential start-up options for mainstream municipal ANAMMOX process, in an upflow anaerobic sludge blanket (UASB) reactor seeded with municipal returned activated sludge (RAS). The micro-granular UASB reactor has been operated under steady-state conditions with average nitrogen loading rate ranging from 1.2 to 0.18 KgN /m3/day and the average SRT of the reactor ranged from 36 to 72 days. Subsequently, a set of manometric batch experiments to evaluate ANAMMOX performance efficiency in different conditions with a distinct emphasis on high-temperature mainstream conditions. To better assess the response and overall performance of the ANAMMOX system in a long-term operation period and to evaluate the possibility of using mathematical modelling for process prediction, intended for potential future scale-ups, a BioWin model was adapted. The results of this study, provide an alternative and efficient configuration for ANAMMOX cultivation and demonstrate the effectiveness and high performance efficiency of micro-sized granules in both sidestream and mainstream ANAMMOX processes. The section of the research focusing on mainstream processes highlights the factors monitoring and promoting the growth of ANAMMOX bacteria in mainstream wastewater treatment which can potentially guide the future implementation of ANAMMOX-based technologies. This study also confirms the reliability of ANAMMOX-based process modeling and high predictive ability with BioWin, being a valuable in enhancing the efficiency of UASB-ANAMMOX practical operation in an industrial scale.
Open Access
Behavior of Engineered Cementitious Composite-Repaired Superelastic-Shape Memory Alloy Reinforced Shear Walls
(2020-11-13) Rojas, Michael Armando Soto; Palermo, Dan
Shape Memory Alloys (SMAs) and High-Performance Fiber Reinforced Concretes (HPFRCs) are innovative materials that provide an opportunity to improve the post-earthquake state of reinforced concrete structures, while achieving the design objective. The combination of these two materials lead to self-centering with improved damage tolerance. In this research, previously tested, Superelastic-Shape Memory Alloy (SE-SMA) and typical-steel reinforced concrete shear walls are repaired and tested under the same simulated seismic loading. The repairing method involved the removal of the heavily damaged concrete in the plastic hinge zone, replacement of ruptured and buckled steel reinforcement, and casting of Engineered Cementitious Composite (ECC) where the previous concrete was removed. The numerical modelling and experimental testing of the repair technique highlight that the brittle behavior of concrete in tension and its deformation incompatibility with reinforcing steel bars, and yielding of steel reinforcement are suppressed by establishing a composite system that integrates the self-centering phenomenon of SE-SMA and the distinctive ductility properties of ECC.
Open Access
Behaviour and Analysis of Strain Hardening Fiber Reinforced Cementitious Composites Under Shear and Flexure
(2019-03-05) Eshghi, Najmeh; Pantazopoulou, Stavroula
Significant effort has been vested over the years in quantifying the contribution of concrete to the shear strength of concrete members. By introduction of novel cementitious material, a much greater need to develop a standard to treat the concrete in a systematic manner is felt. In this thesis, an alternative framework of analysis to interpret the shear failure and the corresponding strength of the failure mechanism is suggested which gives an insight into a new interpretation of shear failure and relates to the state of bond of reinforcement over the entire span of a member. This approach is adaptable to be used for new concrete materials such as Strain Hardening Fiber Reinforced Cementitious Composites. An experimental program is also designed to provide a basis for the development of design rules which are prerequisite for the introduction of these novel materials in new construction. All experiments are conducted at York University.
Open Access
BIM and Fire Safety Engineering for Wood Structures
(2023-12-08) Davidson, Anne Charlette; Gales, John A.
This thesis provides a map for Fire Safety Engineering (FSE) practitioners who are navigating the complicated and under-studied research area of mass timber in fires and how such a project would fit into the BIM design process. The thesis expands the field of knowledge on how architectural features correlate with fire dynamic outcomes of full scale CLT compartments, provides baseline fire metrics for Eastern Hemlock without any existing published data, and provides a wholistic interpretation of the performance of a traditional mortise and tenon timber frame connection in a fire test, also without any existing publications. The thesis also provides an option for how each project might be included in BIM and any research or requirements that would allow for total integration, as well as the potential benefits.
Open Access
Biodegradability Enhancement in Municipal Wastewater Using New Environmentally Friendly Biostreme
(2018-03-01) Izadi, Parin; Eldyasti, Ahmed
Microorganisms metabolic rate is the ultimate operational basis of diverse biological treatment processes. A variety of assorted factors can affect the biological wastewater treatments metabolic rate. One of the prominent means, is the use of supplements such as trace metals and vitamins. Both batch and continuous experiments have been used to study the effect of a variety of trace metals solution (named biostreme solution) and vitamins solution on biological organic removal process. The results show that, in average addition of 500 ppm of the biostreme had the highest rate of organic removal. The colloidal removal was enhanced by a rate of between 65 to 75% in specific batch tests. When the wastewater was supplemented with concentrations of biostreme individually and in a mixture with the vitamins solution, chemical oxygen demand fractionation showed a significant decrease in the colloids, however there is a different effect observed when returned activated sludge was used as the seed.
Open Access
Biodegradation of Perfluorocarboxylic Acid in Landfill Leachate
(2024-03-16) Shu, Xuhan; Brar, Satinder K.
Long-chain perfluoro carboxylic acids (LC-PFCAs), a subset of perfluorochemicals (PFCs), were identified in landfill leachate during the sampling period from June 2022 to July 2023. In this thesis, the exclusive focus is on the chemical degradation of PFCAs, omitting biological degradation experiments due to their persistent nature. The leachate analysis revealed a seasonal fluctuation in its chemical characteristics including nitrogen, phosphate, alkalinity, pH, and chemical oxygen demand (COD). Interestingly, the selected C9 and C10 LC-PFCAs were consistently present in the leachate but did not show any significant seasonal variation. Concentrations of LC-PFCAs ranged from 100 ng/L to 800 ng/L. To assess the biodegradability of C9 and C10 PFCA in the leachate using native microorganisms, a bench-scale experiment was conducted. The microbial community exhibited biphasic growth when exposed to the specified PFCAs (10-100 mg/L) for 6 days. Notably, the C9 and C10 PFCAs displayed a biodegradation efficiency of up to 58% within this 6-day period.
Open Access
Biological Conversion Process of Methane into Methanol Using Mixed Culture Methanotrophic Bacteria Enriched from Activated Sludge System
(2018-03-01) Mahmoud, Ahmed Mohamed AlSayed; Eldyasti, Ahmed
Wastewater treatment plants contribute to the global warming phenomena not only by GHG emissions, but also, by consuming enormous amount of fossil fuel based energy. Therefore, methane bio-hydroxylation has attracted the attention as methanol is an efficient substitute for methane (GHG) due to its transportability and higher energy yield. This work is destined to investigate and optimize the factors affecting the microbial activity within methane bio-hydroxylation system using type I methanotrophs enriched from activated sludge system. The optimization resulted in a notable enhancement of the growth kinetics. The attained maximum specific growth rate (max) (0.358 hr-1) and maximum specific methane biodegradation rate (qmax) (0.605 g-CH4,Total/g-DCW/hr-1) were the highest reported in mixed cultures. Furthermore, the maximum methanol productivity achieved is comparable with pure cultures and equal to 211581 mg/L/day. Whereas, methanol concentration of 48521 mg/L was attained which is two times higher than the reported using mixed culture.
Open Access
Bond Behaviour of Steel Reinforcing Bars Embedded in Ultra-High-Performance Steel Fiber Reinforced Concrete
(2019-07-02) Saikali, Elisabeth Rita; Pantazopoulou, Stavroula; Palermo, Dan
Ultra-High-Performance Steel Fiber Reinforced Concrete (UHP-SFRC) is an emerging concrete considered as an optimal, durable material that can substitute conventional concrete owing to its distinct fresh and hardened properties. Thus, it is essential to understand the mechanism of stress transfer between this concrete and conventional reinforcement that permits the composite action of both materials. A four-point bending test program (FPBT) was arranged and conducted on 19 beams designed for the bond development to occur in the constant moment region along a short embedment length in order to achieve a uniform distribution of bond stresses, enabling measurement of bond strength through reverse engineering of beam strength and deformation. Additional material testing was conducted on prisms under 4-point loading in order to extract the mechanical properties for all material mixes considered. The bond-specimens failed either by pullout or by cone formation with minimal deterioration of the concrete cover, illustrating the high confinement provided by the novel concrete surrounding the bar in tension. The bond strength was determined to be directly proportional to the tensile strength capacity of the design mix, where for the strongest material the bond strength was approximately 30 MPa. Moreover, the test results indicated a very ductile flexural beam response accompanied by significant mid-span deflection reaching 27 mm and substantial bar-slip values attaining 19 mm. Different UHP-SFRC mixes, concrete covers, and embedment lengths were considered. A numerical model was developed to simulate the FPBT using a nonlinear finite element analysis platform, VecTor2, with the ability to model this novel concrete. This high bond strength provided by the concrete cover enables a significant reduction in the design development length as compared to what is used today for conventional concrete.
Open Access
Bond Strength of Ultra-High-Performance Concrete Under Direct Tension Pullout
(2019-07-02) Tsiotsias, Konstantinos; Pantazopoulou, Stavroula
Bond occurs at the interface between the reinforcing bars and the cover concrete and enables force transfer between the two media. Thirteen specimens comprising four distinct UHPC or ECC (Engineered Cementitious Composite) material compositions and two different values cover thicknesses to the embedded bar were tested. Experimental results were compared with bond strength values obtained from beam tests where anchorage length in the constant moment region and material properties were the same. Bond strength measurements obtained from the DTP setup were half the corresponding values obtained from beam specimens, whereas the DTP setup showed more sensitivity to the increase of the cover thickness. Detailed nonlinear finite element analysis was conducted using two alternative levels of approximation in modeling the bar matrix interface. The occurrence of unaccounted for confining pressures and restraint effects were shown in conventional pullout methods, while the DTP setup provided the most conservative estimate of bond strength.