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Full-Text Articles in Engineering

Water Supply Capacity Development In The Context Of Global Change, Patrick Breach Apr 2020

Water Supply Capacity Development In The Context Of Global Change, Patrick Breach

Electronic Thesis and Dissertation Repository

The ANEMI model is an integrated assessment model of global change that emphasizes the role of water resources. The model is based on the principles of system dynamics simulation in order to analyze changes in the Earth system using feedback processes. Securing water resources for the future is a key issue of global change, and ties into global systems of population growth, climate change carbon cycle, hydrologic cycle, economy, energy production, land use and pollution generation.

This thesis focusses on the development of global water supplies necessary to keep pace with a growing population and global economy using an integrated …


Using A Systems Approach To Analyze The Operational Safety Of Dams, Leanna M. King Apr 2020

Using A Systems Approach To Analyze The Operational Safety Of Dams, Leanna M. King

Electronic Thesis and Dissertation Repository

Dam systems are arrangements of interacting components that store and convey water for beneficial purposes. Dam failures are associated with extreme consequences to human life, the environment and the economy. Existing techniques for dam safety analysis tend to focus on verifying system performance at the edge of the design envelope. In analyzing the events which occur within the design envelope, linear chain-of-events models are often used to analyze the potential outcomes for the system. These chain-of-events models require that combinations of conditions are identified at the outset of the analysis, which can be very cumbersome given the number of physically …


Lateral Load Analysis Of Multi-Storey Light-Frame Wood Buildings Through Detailed And Simplified Numerical Approaches, Chu Peng Mar 2020

Lateral Load Analysis Of Multi-Storey Light-Frame Wood Buildings Through Detailed And Simplified Numerical Approaches, Chu Peng

Electronic Thesis and Dissertation Repository

Increasing global demand for a sustainable society is driving the development of multi-storey light-frame wood structures (LFWSs). A high-resolution finite element modelling (FEM) procedure for three-dimensional multi-storey LFWS buildings is developed. This tremendous effort is carried out to have a benchmark model that can be used for the validation of simpler models and for the assessment of the structural performance considering system effects. High-resolution FEM of all components of a building is not practical. A simplified FEM procedure is developed based on equal work principle. Verification of the accuracy of the high-resolution model is undertaken by comparing the natural frequencies …


Quantification Of Septic System Contribution To Nutrient Loads In Surface Waters, Archana Tamang Mar 2020

Quantification Of Septic System Contribution To Nutrient Loads In Surface Waters, Archana Tamang

Electronic Thesis and Dissertation Repository

Freshwater systems worldwide are threatened by excessive nutrient (nitrogen and phosphorus) loading. This study evaluated the contribution of septic systems to stream nutrient loads in nine subwatersheds. Stream sampling was conducted during low and high discharge conditions, with samples analyzed for total phosphorus (TP), soluble reactive phosphorus (SRP), nitrate (NO3-N), and acesulfame (ACE; wastewater tracer). Higher septic effluent reached the subwatershed outlets during high discharge conditions. Subwatersheds with newer households had a lower percentage of septic effluent reaching the stream compared with subwatersheds with older households. Seasonal and event-based ACE concentration-discharge relationships revealed that the hydrological pathways delivering …


Smouldering Combustion Treatment Of Soils And Granular Activated Carbon Contaminated With Per- And Polyfluoroalkyl Substances, Alexandra L. Duchesne Mar 2020

Smouldering Combustion Treatment Of Soils And Granular Activated Carbon Contaminated With Per- And Polyfluoroalkyl Substances, Alexandra L. Duchesne

Electronic Thesis and Dissertation Repository

Per- and polyfluoroalkyl substances (PFAS) are emerging contaminants, ubiquitous in the environment, and are challenging to remediate. Self-sustaining Treatment for Active Remediation (STAR) destroys organic contaminants embedded in porous media using smouldering combustion. Self-sustaining smouldering conditions allow the reaction to propagate through the contaminated media without external energy. This study explored STAR as a remediation option for PFAS-impacted granular activated carbon (GAC) and PFAS-contaminated soil. Three smouldering mixtures were used (i) PFAS-spiked GAC and sand, (ii) PFAS-spiked soil and GAC, (iii) PFAS-contaminated field site soil and GAC. Smouldering temperatures were greater than 900˚C, destroying the GAC. Post-treatment PFAS concentrations of …


Advanced Hardware And Software Approach To Seismic Site Response Investigations, Aleksandar Dimitrov Mihaylov Feb 2020

Advanced Hardware And Software Approach To Seismic Site Response Investigations, Aleksandar Dimitrov Mihaylov

Electronic Thesis and Dissertation Repository

Vibration measurement is an essential aspect of modern geotechnical engineering. It is particularly vital task for measuring the dynamic soil parameters, estimating seismic hazards and evaluating influence of industrial, traffic and construction vibrations on the surrounding buildings, structures and their elements. Meanwhile, commercial exploration seismic stations and data acquisition systems require significant professional knowledge and training in geophysics or vibration measurement, as well as practical skills and experience in adjusting data acquisition parameters. Furthermore, available seismological investigation and vibrometry sensors are not universally suitable for field applications in geophysical studies, soil-structure interaction investigations or structural vibrations. The frequency range suitable …


Progressive Failure Of Transmission Line Towers Under Different Tornado Wind Fields, Wesam Abdelhamid Mohamed Feb 2020

Progressive Failure Of Transmission Line Towers Under Different Tornado Wind Fields, Wesam Abdelhamid Mohamed

Electronic Thesis and Dissertation Repository

High-intensity wind events (downbursts and tornadoes) cause the majority of weather-related transmission line (TL) failures, which detrimentally affect society. This study investigates the progressive failures of single TL towers and TL systems under different F2 tornadoes. Different tornado wind fields are incorporated in a fluid-structure software developed at Western University. Progressive failure analysis is then conducted for four towers under the most critical tornado configurations identified from extensive parametric studies. Moreover, the cost associated with designing TLs to sustain F2 tornadoes is investigated by strengthening the TL towers. Finally, the progressive failure within self-supported TL systems under different tornadoes, and …


System Reliability Analysis Of Defected Pile Group Foundations, Abdalla E. Adlan Alhashmi Jan 2020

System Reliability Analysis Of Defected Pile Group Foundations, Abdalla E. Adlan Alhashmi

Electronic Thesis and Dissertation Repository

Deep foundations design suffers some degrees of uncertainties. This thesis studies the behavior of defected pile group foundations installed in sand and calibrates the resistance factor of pile group foundation, utilizing a rational based system reliability analysis. This was achieved by conducting a comprehensive numerical parametric investigation using the computer program ABAQUS/Standard. The result of the parametric study showed that the presence of a defected pile in a pile group foundation causes lateral deflection of the pile cap and hence induces bending moment at the adjacent piles which affects the load distribution mechanism of the system. It was also found …


Effects Of Drinking Water Treatment Processes On Removal Of Algal Matter And Subsequent Water Quality, Ziming Zhao Jan 2020

Effects Of Drinking Water Treatment Processes On Removal Of Algal Matter And Subsequent Water Quality, Ziming Zhao

Electronic Thesis and Dissertation Repository

Seasonal algal blooms in drinking water sources have increased significantly over the recent past as a result of increased temperature and nutrient loading in surface water due to agricultural and surface runoff. More than 95% of algal cells can be removed by coagulation and flocculation processes. However, algal organic matter (AOM) is not removed well during coagulation, thus causes several operational challenges in drinking water treatment. This research was conducted to investigate the effectiveness of coagulation, granular activated carbon adsorption, and filtration processes on AOM removal and to evaluate disinfection by-products formation potential with/without UV irradiation.

Initially, coagulation performance for …


The Influence Of Porous Media Heterogeneity On Smouldering Remediation, Jiahao Wang Jan 2020

The Influence Of Porous Media Heterogeneity On Smouldering Remediation, Jiahao Wang

Electronic Thesis and Dissertation Repository

Smouldering remediation is a promising technique for destroying organic contaminants in soil. Forced airflow is vital to supporting the smouldering reaction and to propagate it through the contaminated zone. This research focuses on investigating the effects of permeability heterogeneity on smouldering. A series of unique column experiments, combined with numerical model simulations, were conducted. The results suggest that smouldering can successfully propagate through layers in series despite more than a 1000:1 permeability contrast. However, extinction can occur in the finer layer when smouldering propagates through layers in parallel with a permeability ratio above 3:1. Extinction may occur due to insufficient …


Seismic Performance Of Superelastic Shape Memory Alloy Reinforced Concrete Shear Wall Systems, Emad A. Abraik Jan 2020

Seismic Performance Of Superelastic Shape Memory Alloy Reinforced Concrete Shear Wall Systems, Emad A. Abraik

Electronic Thesis and Dissertation Repository

A major sustainability issue for reinforced concrete (RC) structures is the residual deformations caused by the yielding of the steel bars during extreme seismic events. Numerous efforts have been made to develop self-centering structures, which minimize these deformations and the associated seismic damage. Superelastic shape memory alloys (SE-SMA) can be utilized in concrete elements to achieve such behaviour. This thesis focuses on the use of SE-SMA bars in RC walls.

First, the thesis starts by conducting a fragility analysis to assess the seismic performance and vulnerability of ten and twenty-story SE-SMA RC walls. SE-SMA bars are used within the plastic …