http://hdl.handle.net/1974/765 Fri, 24 May 2013 09:24:34 GMT 2013-05-24T09:24:34Z http://hdl.handle.net/1974/8009 Title: The Effects of Elevated Temperatures on Fibre Reinforced Polymers for Strengthening Concrete Structures Authors: Eedson, Robert Abstract: The use of fibre reinforced polymer (FRP) composites for strengthening reinforced concrete structures has become increasingly popular in recent years. However, before FRPs can be implemented in interior building applications their performance during fire must be assessed and understood. There currently remains a paucity of information in this area for most currently available FRP strengthening systems. This thesis presents a study of the mechanical and bond properties of selected currently available FRP strengthening systems for concrete structures at elevated temperatures such as might be experienced during a fire. Testing has been performed and is reported to study the continuous unidirectional coupon tensile strength, lap-splice FRP-to- FRP shear bond strength and tensile elastic modulus at elevated temperatures. Results of thermal characterization tests are also completed in an attempt to relate properties of the polymer matrix, such as the glass transition temperature, and thermal decomposition temperature to the losses of strength and stiffness observed for FRP coupons during steady-state and transient exposure to elevated temperatures up to 200oC. A simple analytical model is presented, for which the input parameters can be determined using dynamic mechanical thermal analysis and thermogravimetric analysis, to describe the reduction in mechanical and bond properties of the FRP systems at elevated temperatures. Based on this testing and subsequent analysis it is recommended that a conservative limit on the allowable temperature exposure for FRP systems during fire be set as the glass transition temperature measured using dynamic mechanical thermal analysis. Furthermore it is suggested that differential scanning calorimetry may not be an appropriate method of determining the glass transition temperature for available FRP systems used in concrete strengthening applications. Description: Thesis (Master, Civil Engineering) -- Queen's University, 2013-04-30 19:06:24.31 Wed, 01 May 2013 04:00:00 GMT http://hdl.handle.net/1974/8009 2013-05-01T04:00:00Z http://hdl.handle.net/1974/7914 Title: FIELD AND LAB SCALE PERFORMANCE OF PHOSPHORUS REMOVAL IN POST-WETLAND SLAG FILTERS TREATING AQUACULTURE WASTEWATER IN COLD CLIMATES Authors: Sansford, LAUREN Abstract: Eutrophication, caused by phosphorus and nitrogen overloading, is a global pollution problem for our fresh water lakes and streams. Regulatory bodies have developed treatment guidelines for point-source pollution to address this concern, creating a need for small and remote waste producers to develop low cost solutions for nutrient removal – in particular phosphorus. Constructed wetlands have often been implemented as a low cost alternative to treat various sources of wastewater, however, their efficiency in removing phosphorus has been questioned. Post-treatment blast furnace slag filters (known to have a high phosphorus sorption capacity) have been in operation since 2008 in Haliburton, Ontario, Canada, treating aquaculture wastewater following treatment by a constructed wetland. Phosphorus removal performance of three filters of varying configuration have been assessed: • a random packed filter, packed randomly with unsieved blast furnace slag removed only 26% of phosphorus overall and became severely clogged likely due to the presence of fines, poor flow distribution and formation of calcium carbonate precipitate; • a screen filter, designed as twenty individual filters separated by 3 inches of space to provide more uniform flow throughout removed 55% of the total phosphorus added and maintained a uniform flow throughout the study; and • an anaerobic filter, designed to be sealed from the atmosphere in an effort to prevent the formation of calcium carbonate and subsequent filter clogging, removed 19% of the total phosphorus added and revealed signs of poor flow distribution. Lab-scale flow through cells were designed to parallel the field scale studies and were operated at varying configuration, temperature and residence times to assess these factor effects on phosphorus removal. The results of this research provide a valuable contribution to research involving blast furnace slag filters for phosphorus removal. It has been demonstrated that cold temperatures reduce the slag filter’s efficiency to remove phosphorus (but cold-climate filters can still be effective in removing phosphorus), the removal of slag fines reduces the potential for slag clogging, a screen design is effective in promoting uniform flow and offsetting the effects of clogging and an optimum residence time may exist for phosphorus removal beyond which phosphorus removal is minimal. Description: Thesis (Master, Civil Engineering) -- Queen's University, 2013-04-23 21:46:44.136 Wed, 24 Apr 2013 04:00:00 GMT http://hdl.handle.net/1974/7914 2013-04-24T04:00:00Z http://hdl.handle.net/1974/7895 Title: WATER DISTRIBUTION SYSTEM DESIGN AND REHABILITATION UNDER CLIMATE CHANGE MITIGATION SCENARIOS Authors: Roshani, EHSAN Abstract: The water industry is a heavy consumer of electricity to pump water. Electricity generated with fossil fuel sources produce greenhouse gas (GHG) emissions that contribute to climate change. Carbon taxation and economic discounting in project planning are promising policies to reduce GHG emissions. The aim of this research is to develop novel single- and multi-objective optimization frameworks that incorporate a new gene-coding scheme and pipe ageing models (pipe roughness growth model, a pipe leakage model, and a pipe break model) to examine the impacts of a carbon tax and low discount rates on energy use, GHG emissions, and design/operation/rehabilitation decisions in water systems. Chapter 3 presents a new algorithm that optimizes the operation of pumps and reservoirs in water transmission systems. The algorithm was applied to the KamalSaleh transmission system near Arak, Iran. The results suggest that a carbon tax combined with a low discount rate produces small reductions in energy use and GHG emissions linked to pumping given the high static head of the KamalSaleh system. Chapter 4 presents a new algorithm that optimizes the design and expansion of water distribution networks. The algorithm was applied to the real-world Fairfield water network in Amherstview, Ontario, Canada. The results suggest that a carbon tax combined with a low discount rate does not significantly decrease energy use and GHG emissions because the Fairfield system had adequate installed hydraulic capacity. Chapters 5 and 6 present a new algorithm that optimizes the optimal rehabilitation type and timing of water mains in water distribution networks. In Chapter 5, the algorithm is applied to the Fairfield network to examine the impact of asset management strategies (quantity and infrastructure adjacency discounts) on system costs. The results suggest that applying discounts decreased capital and operational costs and favored pipe lining over pipe replacement and duplication. In Chapter 6, the water main rehabilitation optimization algorithm is applied to the Fairfield network to examine the impact of a carbon tax and low discount rates on energy use and GHG emissions. The results suggest that adopting a low discount rate and levying a carbon tax had a small impact in reducing energy use and GHG emissions and a significant impact in reducing leakage and pipe breaks in the Fairfield system. Further, a low discount rate and a carbon tax encouraged early investment in water main rehabilitation to reduce continuing leakage, pipe repair, energy, and GHG costs. Description: Thesis (Ph.D, Civil Engineering) -- Queen's University, 2013-04-21 13:58:08.302 Mon, 22 Apr 2013 04:00:00 GMT http://hdl.handle.net/1974/7895 2013-04-22T04:00:00Z http://hdl.handle.net/1974/7888 Title: STABILITY OF BURIED STEEL AND GLASS FIBRE REINFORCED POLYMER PIPES UNDER LATERAL GROUND MOVEMENT Authors: Almahakeri, MOHAMED Abstract: As vast networks of high pressure buried energy pipelines traverse North America and other continents, the stability of such essential buried infrastructure must be maintained under a variety of earth loading conditions. The pipe-soil interaction and the longitudinal behaviour of buried pipes due to relative ground movements is poorly understood. This thesis presents full scale testing and numerical modeling of steel and Glass Fibre Reinforced Polymer (GFRP) pipelines to better understand the flexural performance of buried pipes subjected to lateral earth movement. For the experimental phase of the study, a series of pipe bending experiments have been conducted on 102 mm nominal diameter and 1830 mm long steel and GFRP pipes buried in dense sand. Pipe loading was carried out by pulling pipe ends using two parallel cables attached to a spreader beam outside the test region, using a hydraulic actuator. The different tests covered burial depth-to-diameter (H/D) ratios of 3, 5 and 7. During the steel pipe testing phase, special consideration was given to assess the effect of boundary limits, friction within the pulling mechanism, and consistency of results using repeated tests. For the GFRP pipes, the experimental work investigated the effect of the laminate structure of the pipes, including both cross-ply and angle-ply laminates. Test results showed that burial depth significantly influenced the ultimate pulling forces, longitudinal strains, and pipe net deflection at mid-span. The results were also compared between the two types of pipes. The failure mechanism for all tests was consistently governed by soil failure, except for the angle-ply GFRP pipe that failed at a burial depth of H/D=7. For the numerical analysis, the study presents the development and verification of two and three-dimensional numerical models including material constitutive models for both the pipe and for the soil using a stress-dependent modulus. Calculations are presented for different burial depths and are compared to experimental data. It was shown that the numerical model can successfully capture the pipe-soil interaction behaviour for both pipe types in terms of load-displacement responses and net bending deflection. Also, the effect of material variation and laminate structure were in agreement with test data. Description: Thesis (Ph.D, Civil Engineering) -- Queen's University, 2013-04-18 22:21:53.025 Fri, 19 Apr 2013 04:00:00 GMT http://hdl.handle.net/1974/7888 2013-04-19T04:00:00Z