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Large diameter piles are widely used as foundations to support buildings, bridges, and other structures. As a result, it is critical for the field to have an optimized approach for quality control and efficiency purposes to measure the suggested number of load tests and the required measured capacities driven piles. In this thesis, an analysis of a load test program designed for proposed bridge replacements at Kentucky Lake is performed. It includes a detailed site exploration study with in-situ and laboratory testing. The pile load test program included monitoring of a steel H-pile and steel open ended pipe pile during driving and static loading. The pile load test program included static and dynamic testing at both pile testing locations. Predictions of both pile capacities were estimated using commonly applied failure criterion, and a load transfer analysis was carried out on the dynamic and static test data for both piles. The dynamic tests were then compared to the measured data from the static test to examine the accuracy. This thesis concludes by constructing t-z and q-z curves and comparing the load transfer analyses of the static and dynamic tests.

Published scientific work indicates that residential large diameter drinking water wells are at a higher risk of contamination from surface water impacts than drilled wells. The possibility of a higher incidence of contamination of large diameter wells is attributed to site selection and construction problems such as leaking joints in the well casing, ineffective annular sealant placed between the well casing and the formation, a poorly fitted cover with an access lid that promotes contaminant entry and air entry without adequate air filtration, well location down gradient of septic effluent sources, and depth limitations due to improper equipment used to advance the well which results in shallow wells often situated in topographical lows. In some situations, flaws in the well design were actually deliberate measures intended to capture surface water at sites with low groundwater yield. Historically, residential drinking water well performance studies have focussed on existing wells; however, uncertainty in the actual well construction methods and materials, well age and maintenance efforts have been problematic. A field and laboratory study was completed to assess the performance of several design changes that were thought to improve the integrity of large diameter drinking water wells, and to determine whether one design is more prone to atmospheric and/or surface water contamination than the other. Four large diameter residential wells were installed at a study site in Lindsay, Ontario. Three of these wells are constructed with enhanced construction methods (two using a cement tile casing and one using a galvanized steel casing) and annular sealants, while the fourth was constructed using conventional methods for cement cased wells. The enhanced test wells utilized a sealant between the casing sections, various annular sealants between the formation and the well casing, sanitary waterline connections, and ventilation with air filtration. The well constructed using outdated methods did not have any of these advanced features. An automated water extraction system removed about 875 L/day from each well to mimic residential usage. Routine monitoring, and laboratory and field testing were used to collect pertinent data required for this performance assessment. Routine monitoring involved the visual inspection of the wells, collection of well water elevation, collection of soil temperature profile data, collection and analysis of water samples, and collection of cumulative water volumes purged from the test wells. A biofilm cleaning study and analysis of cement-bentonite grout was conducted in the laboratory while smoke and aqueous tracer tests were conducted in the field. The biofilm cleaning study entailed growing a biofilm on different large diameter well casing materials and applying cleaning methods thought to be practical for cleaning the interior walls of large diameter wells. Different mixtures of cement-bentonite grout were subjected to volume measurements, vertical load bearing capacity analysis, and hydraulic conductivity analysis to determine their suitability as a potential annular sealant. The tracer tests were developed to determine whether pathways for either airborne contaminants or surface water to enter the test wells exist. The test wells were filled with smoke and monitored for potential atmospheric pathways. A tracer solution was infiltrated around the test wells and the interior of the tests wells were monitored for potential pathways for surface water to enter. Bacteriological indicators were detected in all test wells. The smoke tracer tests demonstrated that pathways for airborne contaminants to enter the test wells exist with more pathways observed in the winter than the summer. The aqueous tracer tests highlighted several areas where surface water could enter the test wells if ponding occurred around the well casing. As expected the enhanced test wells performed much better than the conventional test well for both of these tracer tests. The results of the biofilm cleaning study indicated that galvanized steel or fibreglass casing materials were the only materials able to be cleaned effectively. The best method in this study to remove biofilm from casing materials was pressure washing. The results from the cement-bentonite grout investigation indicated that cement-bentonite grout with 5% bentonite would make the most suitable annular sealant as its volume changed the least during curing, it was strong enough to support the load from maintenance efforts, and was the most impervious. The results of this study indicate that large diameter wells constructed with a proper annular sealant, sealant between casing sections and a sanitary waterline connection are less prone to contamination. Monitoring of the test wells should continue as they mature to determine whether this plays a significant role in their ability to prevent contamination of large diameter wells. Smoke tracer tests should be conducted again during the winter to determine if temperature was the cause of increased atmospheric pathways. A field-scale method to remove biofilm from the interior casing wall of large diameter wells should be developed and tested. A field-scale investigation of cement-bentonite grout for use as an annular sealant should be completed. Fibreglass casings can be fabricated as a continuous piece with no seams or joints and hence another well should be constructed and studied using corrugated fibreglass (NSF ANSI 61) casing.

Published scientific work indicates that residential large diameter drinking water wells are at a higher risk of contamination from surface water impacts than drilled wells. The possibility of a higher incidence of contamination of large diameter wells is attributed to site selection and construction problems such as leaking joints in the well casing, ineffective annular sealant placed between the well casing and the formation, a poorly fitted cover with an access lid that promotes contaminant entry and air entry without adequate air filtration, well location down gradient of septic effluent sources, and depth limitations due to improper equipment used to advance the well which results in shallow wells often situated in topographical lows. In some situations, flaws in the well design were actually deliberate measures intended to capture surface water at sites with low groundwater yield. Historically, residential drinking water well performance studies have focussed on existing wells; however, uncertainty in the actual well construction methods and materials, well age and maintenance efforts have been problematic. A field and laboratory study was completed to assess the performance of several design changes that were thought to improve the integrity of large diameter drinking water wells, and to determine whether one design is more prone to atmospheric and/or surface water contamination than the other. Four large diameter residential wells were installed at a study site in Lindsay, Ontario. Three of these wells are constructed with enhanced construction methods (two using a cement tile casing and one using a galvanized steel casing) and annular sealants, while the fourth was constructed using conventional methods for cement cased wells. The enhanced test wells utilized a sealant between the casing sections, various annular sealants between the formation and the well casing, sanitary waterline connections, and ventilation with air filtration. The well constructed using outdated methods did not have any of these advanced features. An automated water extraction system removed about 875 L/day from each well to mimic residential usage. Routine monitoring, and laboratory and field testing were used to collect pertinent data required for this performance assessment. Routine monitoring involved the visual inspection of the wells, collection of well water elevation, collection of soil temperature profile data, collection and analysis of water samples, and collection of cumulative water volumes purged from the test wells. A biofilm cleaning study and analysis of cement-bentonite grout was conducted in the laboratory while smoke and aqueous tracer tests were conducted in the field. The biofilm cleaning study entailed growing a biofilm on different large diameter well casing materials and applying cleaning methods thought to be practical for cleaning the interior walls of large diameter wells. Different mixtures of cement-bentonite grout were subjected to volume measurements, vertical load bearing capacity analysis, and hydraulic conductivity analysis to determine their suitability as a potential annular sealant. The tracer tests were developed to determine whether pathways for either airborne contaminants or surface water to enter the test wells exist. The test wells were filled with smoke and monitored for potential atmospheric pathways. A tracer solution was infiltrated around the test wells and the interior of the tests wells were monitored for potential pathways for surface water to enter. Bacteriological indicators were detected in all test wells. The smoke tracer tests demonstrated that pathways for airborne contaminants to enter the test wells exist with more pathways observed in the winter than the summer. The aqueous tracer tests highlighted several areas where surface water could enter the test wells if ponding occurred around the well casing. As expected the enhanced test wells performed much better than the conventional test well for both of these tracer tests. The results of the biofilm cleaning study indicated that galvanized steel or fibreglass casing materials were the only materials able to be cleaned effectively. The best method in this study to remove biofilm from casing materials was pressure washing. The results from the cement-bentonite grout investigation indicated that cement-bentonite grout with 5% bentonite would make the most suitable annular sealant as its volume changed the least during curing, it was strong enough to support the load from maintenance efforts, and was the most impervious. The results of this study indicate that large diameter wells constructed with a proper annular sealant, sealant between casing sections and a sanitary waterline connection are less prone to contamination. Monitoring of the test wells should continue as they mature to determine whether this plays a significant role in their ability to prevent contamination of large diameter wells. Smoke tracer tests should be conducted again during the winter to determine if temperature was the cause of increased atmospheric pathways. A field-scale method to remove biofilm from the interior casing wall of large diameter wells should be developed and tested. A field-scale investigation of cement-bentonite grout for use as an annular sealant should be completed. Fibreglass casings can be fabricated as a continuous piece with no seams or joints and hence another well should be constructed and studied using corrugated fibreglass (NSF ANSI 61) casing.

In the first phase of this project three enhanced large diameter (> 60 cm) residential wells were constructed at a study site in Lindsay, Ontario. Two wells were constructed using concrete tile casing while the other well was constructed using galvanized steel casing. Javor (2010) evaluated various aspects of drinking water well construction and design to determine the susceptibility of residential large diameter drinking water wells to surface water and airborne contamination. One of the purposes of these new installations was to remove the uncertainty with respect to construction methods, age and maintenance that is characteristic of residential drinking water well performance studies. Javor (2010) conducted a field and laboratory study to assess the performance of several design changes that were thought to improve the integrity of large diameter drinking water wells. These experiments were also used to determine whether one design was more prone to atmospheric and/or surface water contamination than another. During the second phase of this project routine monitoring was continued and data pertinent to assess the performance of the test wells were collected using the same instrumentation. This routine monitoring involved the visual inspection of the wells, collection of well water elevation, collection of soil temperature profile data, collection and analysis of water samples, and collection of cumulative water volumes extracted from the test wells. In addition to the routine monitoring, a ground penetrating radar (GPR) survey was performed in October 2010 to complement the previous data collected during February 2010. Smoke tracer tests were performed under non-frozen and frozen conditions to re-assess the potential pathways of contaminants between the atmosphere and the interior of the test wells. Bacteriological indicators and high concentrations of two dissolved ions were detected in all test and monitoring wells. The smoke tracer tests demonstrated that pathways for airborne contaminants to enter the test wells exist with similar pathways observed in the winter and the summer. GPR surveys indicated that the bentonite slurry annular sealant was the most homogeneous media. A baseline characterization of the microbial nature of the biofilm performed in three of the test wells (CTH1, ETH1 and ETH3) indicated that the sessile bacteria are more metabolically diverse than suspended bacteria, and that this diversity is even higher in the concrete cased wells. Biofilm characterization performed on concrete, fibreglass and galvanized steel coupons incubated in two of the test wells (concrete and galvanized steel) showed that bacteria in the concrete cased wells barely colonized on fiberglass and galvanized steel, while bacteria in the galvanized steel cased well did not have difficulty colonizing on any of the casing materials. The results of the biofilm cleaning study indicated that the use of pressure washing combined with chlorination effectively removed biofilm grown on galvanized steel and fibreglass casing materials. This study investigated various factors that could affect the performance of large diameter drinking water wells. Since the test wells used in this study were under the direct influence of surface water a comparison between the various annular sealants was problematic. However, the three enhanced test wells outperformed the conventional test well. The observations from the smoke tracer tests performed under non-frozen and frozen conditions indicate that the Poly-Lok lid seam is the most prevalent pathway for airborne contaminants to enter a well. Fibreglass may be the preferred choice for large diameter well casing material since fibreglass is corrosion resistant, lightweight, easy to install, has a high strength to weight ratio, and a greater degree of biofilm was able to be removed from fibreglass casing material than from galvanized steel casing material.

In an effort to increase machining efficiency and minimize costs, research into tool condition monitoring (TCM) systems has focused on developing methods to allow for unmanned machining. For drilling processes, such systems typically use indirect approaches to monitoring the tool condition by measuring spindle torque and feed force as well as vibrations including acoustic emission (AE – mechanical vibrations faster than 100 kHz). This project aimed to advance the state-of-the-art in the area of TCM by developing a method to detect sudden tool failures in large diameter (> 25 mm) indexable insert drills. This project was a continuation of the research conducted by Mr. R. Griffin (a former MSc student), who developed a model capable of predicting long term wear trends in indexable insert drills [1]. Notably, his model was unable to react to sudden tool breakage due to tool chipping, which was addressed by this project as presented in this thesis. In order to develop and train models able to detect sudden tool failure, an experiment was developed and installed in the field of the industry partner of this project. The experiment’s main feature was a pair of AE sensors added to the existing torque and force sensors. On this setup, experiments were conducted by drilling 2251 holes in workpieces using indexable insert drills with or without the insert breaking. When drilling holes without the insert breaking, the holes were named as good ones; and when drilling holes with the insert breaking they were named as bad holes. During the drilling process, data was collected from current sensors attached to the spindle motor and feed motor as well as from an AE sensor on the spindle and on the workpiece. From the signals from the spindle motor current and feed motor current sensors, algorithms were developed to identify and divide the signals of drilling a hole into different sections of the drilling cycle (i.e. entrance, steady-state, exit, etc.). Steady-state time-domain features were extracted from the sensor signals measured for all holes drilled in the experiments and the extracted features were used to train and test the classifier models. These models were cross validated to determine which type of model was the best fit for the drilling data collected. The results from the classifier models show that most of the classifiers tested have the ability to identify sudden tool breakage based on the data recorded in the present study, with varying degrees of success. The naïve Bayes classifier was able to detect the most failures but suffered from a large number of falsely detected failures. Both the classification tree and linear discriminant analysis classifiers had lower failure detection rates than the naïve Bayes classifier, but did not suffer from the same amount of false positives; as such, these two classifiers had higher overall classification rates than the naïve Bayes. These results suggest that classification tree and linear discriminant analysis methods are better suited for the drilling application and that the time-domain features should be complemented by others, such as the features extracted from the frequency domain, to accurately diagnose the tool condition. Future research should focus on extracting frequency and time-frequency domain features as these features might contain more information on tool condition. In addition, methods of examining features at the entrance and exit of the holes should be investigated as these two points in the drilling cycle are the most prone to sudden tool failure.

In the first phase of this project three enhanced large diameter (> 60 cm) residential wells were constructed at a study site in Lindsay, Ontario. Two wells were constructed using concrete tile casing while the other well was constructed using galvanized steel casing. Javor (2010) evaluated various aspects of drinking water well construction and design to determine the susceptibility of residential large diameter drinking water wells to surface water and airborne contamination. One of the purposes of these new installations was to remove the uncertainty with respect to construction methods, age and maintenance that is characteristic of residential drinking water well performance studies. Javor (2010) conducted a field and laboratory study to assess the performance of several design changes that were thought to improve the integrity of large diameter drinking water wells. These experiments were also used to determine whether one design was more prone to atmospheric and/or surface water contamination than another. During the second phase of this project routine monitoring was continued and data pertinent to assess the performance of the test wells were collected using the same instrumentation. This routine monitoring involved the visual inspection of the wells, collection of well water elevation, collection of soil temperature profile data, collection and analysis of water samples, and collection of cumulative water volumes extracted from the test wells. In addition to the routine monitoring, a ground penetrating radar (GPR) survey was performed in October 2010 to complement the previous data collected during February 2010. Smoke tracer tests were performed under non-frozen and frozen conditions to re-assess the potential pathways of contaminants between the atmosphere and the interior of the test wells. Bacteriological indicators and high concentrations of two dissolved ions were detected in all test and monitoring wells. The smoke tracer tests demonstrated that pathways for airborne contaminants to enter the test wells exist with similar pathways observed in the winter and the summer. GPR surveys indicated that the bentonite slurry annular sealant was the most homogeneous media. A baseline characterization of the microbial nature of the biofilm performed in three of the test wells (CTH1, ETH1 and ETH3) indicated that the sessile bacteria are more metabolically diverse than suspended bacteria, and that this diversity is even higher in the concrete cased wells. Biofilm characterization performed on concrete, fibreglass and galvanized steel coupons incubated in two of the test wells (concrete and galvanized steel) showed that bacteria in the concrete cased wells barely colonized on fiberglass and galvanized steel, while bacteria in the galvanized steel cased well did not have difficulty colonizing on any of the casing materials. The results of the biofilm cleaning study indicated that the use of pressure washing combined with chlorination effectively removed biofilm grown on galvanized steel and fibreglass casing materials. This study investigated various factors that could affect the performance of large diameter drinking water wells. Since the test wells used in this study were under the direct influence of surface water a comparison between the various annular sealants was problematic. However, the three enhanced test wells outperformed the conventional test well. The observations from the smoke tracer tests performed under non-frozen and frozen conditions indicate that the Poly-Lok lid seam is the most prevalent pathway for airborne contaminants to enter a well. Fibreglass may be the preferred choice for large diameter well casing material since fibreglass is corrosion resistant, lightweight, easy to install, has a high strength to weight ratio, and a greater degree of biofilm was able to be removed from fibreglass casing material than from galvanized steel casing material.

The design of polyethylene (PE) pipelines for applications in the gas, water and chemical process industries has been based on data mainly obtained from stress rupture testing pipes only. In practice, installations are composed of both extruded pipe and injection moulded fittings which are joined by a fusion welding technique and are very often subjected to internal pressures of a fluctuating nature. Several makes of PE pipe systems were therefore obtained and work was undertaken to fully characterise mechanical performance in terms of internal pressure loadings. Butt-welded test specimens comprising pipe lengths and fittings were subjected to both static and fluctuating conditions at 80°C, at pressures resulting in brittle fractures (below the knee on stress rupture curves) and at frequencies not exceeding 7.5 cpm (0.125 Hz). Resulting fracture surfaces were examined to identify sources of crack initiation and mechanisms of failure. Mechanical behaviour of the PE pipe samples was found to be markedly influenced by the grade of plastics compound, the pipe system dimensions, mould designs and methods of processing. Fatigue loading was the most aggressive test method and significant reductions in lifetimes were observed in fittings or joints between pipes and fittings with only modest increases in the frequency of pressurisation. It was also demonstrated that improved stress rupture behaviour did not necessarily lead to better fatigue performance. For the square-wave loading profiles used, an idea of the relevant failure mechanisms in any given system was obtained by comparing experimental Nf values with those predicted from cumulative damage principles based on Nf=τSR/τmax. In all types of system, failure was initiated at a defect residual from processing or jointing. Over 95% of all small diameter pipe fractures originated from inclusions at or close to the inside wall. They were geometrically and elementally analysed and suggestions made as to their possible origin and means of elimination. For one PE a reasonable correlation was obtained, between lifetime under stress rupture or fatigue and the inclusion size as measured in the fracture plane.

Finite element modeling of laminar shear box testing that consisted of loose sand treated with large diameter prefabricated vertical drains (PVDs), was performed. The objective of the modeling was to evaluate the reliability of the computer program FEQDrain for predicting excess pore pressure ratios (Ru) at sites treated with prefabricated drains. FEQDrain was found to be capable of successfully modeling measured excess pore pressure ratio time histories from the laminar shear box experiment, as long as an appropriate combination of €˜number of equivalent cycles and €˜shaking duration was chosen, and sensitive parameters were in the range of measured values. Hydraulic conductivity, soil compressibility, and cycles to liquefaction are sensitive parameters and govern the computed Ru values.Modeling shows that the loading rate in the laminar shear box (15 cycles at 2 Hz) likely induced higher Ru values than would be expected in a typical earthquake event with a longer duration. The longer duration allows the drains to dissipate pore pressures and prevent liquefaction. The number of equivalent cycles and duration of shaking combinations recommended for various moment magnitudes in the FEQDrain user manual predict lower, but similar Ru versus time curves. Thus, suggesting that PVDs would be equally effective for any size earthquake. However, drains are most effective at preventing liquefaction when earthquake ground motions are long and uniform, rather than short and intense.Results from models in this study compare favorably with those from computer modeling performed by Howell et al. (2014). The individual hydraulic conductivity and compressibility values were different they were somewhat compensating. Similar Ru values can be modeled with different combinations of these parameters.Based on computer analyses, wick drains and 2€ diameter PVDs were found to be relatively ineffective for preventing liquefaction. However, 3€ diameter PVDs are fairly effective but can be overwhelmed during intense shaking. In contrast, 4€ diameter and larger PVDs are significantly more effective.