In warm climates, warm temperatures cause thermal stratification in hydropower reservoirs inhibiting mixing and leading to deoxygenation of waters at depth (hypolimnium). Turbines withdrawing water at depth result in low dissolved oxygen (DO) in the downstream flow having a large negative impact on the downstream riverine ecosystem. Legislation in the USA and elsewhere now requires hydropower operators to guarantee meeting minimum DO limits in downstream flows.
The majority of mid-20th century high-rise concrete housing stock have reached the end of their first lifecycle in terms of structural integrity and environmental performance, and the urban planning ideals with which they were designed have made these neighbourhoods irrelevant to the contemporary culture of the city. Solutions for economical, structural, social and technological barriers to developing a secondary system to the building envelope and the restructuring of existing balconies for the overall renewal of tower neighbourhoods will be investigated and proposed in this project.
A new type of ecologic ultra-High-performance glass concrete (UHPGC) has been developed at University of Sherbrooke through the use of waste glass materials of different particle-size distributions derived from glass culets. The developed UHPGC proved to give several technological, economical, and environmental advantages compared to the conventional ultra-high-performance concrete (UHPC). Producing UHPGC mixtures fitting the requirements of infrastructure market has not yet been investigated.
Corrosion of internal reinforcement of concrete bridges represents a significant issue. Due to a presence of deicing salts, cycles of freezing and thawing, sustained and repetitive loads, the concrete loses its ability to protect the internal reinforcement. Unprotected reinforcement starts to corrode sooner than anticipated and, therefore, reduces the bridge service life. To avoid shortening of the service life, and safe cost of maintenance, several types of advanced corrosion resistant materials have been developed.
Surface waters, such as lakes and rivers, often have high amounts of natural organic matter formed from decaying plants and animals. Drinking water treatment plants that use these water sources often face with high levels of carcinogenic chlorine disinfection by-products (DBPs) which are result of reaction between natural organic matters and chlorine that is added to water for disinfection. Canadian water quality guidelines set maximum acceptable levels for these harmful DBPs and hence water treatment plants are obliged to come up with appropriate solutions to meet the guidelines.
Entrepreneurship is the embodiment of innovation and its presence is a significant indicator of the power of an economy. Engineering is an essential sector for production of high technology products, services, and jobs, and is often at the forefront of innovation. This research aims to strengthen the current understanding of entrepreneurial success of engineers in Ontario. Data will be gathered from several academic, and business sources, as well as practicing entrepreneurs with engineering backgrounds.
In recent years technological developments have created a new paradigm where data can be obtained easily and with less effort than in the past. This shift is often called Big Data, and its effects can be seen as in many different fields. This proposal follows the same vein, and focusses on taking advantage of the increasing prevalence of connected devices.
The first part of this thesis project consist in a study of the structural behavior, mainly focusing on shear resistance, of concrete elements affected by alkali-aggregate reaction (AAR), an internal swelling reaction. Especially in the presence of moisture, this reaction causes the concrete to expand and form internal cracks. This expansion and formation of cracks is generally associated with a decrease in the mechanical properties of the concrete material. Shear issues of affected concrete is one critical thing to investigate, as they can lead to brittle failures.
Modelling the movement of water through a hydropower station is an important tool for understanding this very complex behaviour, where water is pushed and pulled through long tunnels and spinning turbines, resulting in a vast range of pressures and speeds. There are generally two types of models: 1-dimensional (1D) models, which are simple and cost-effective, but do not provide adequate detail for the more complex features in the power station. The second type is 3-dimensional (3D) models, which are very detailed but cost both time and money.