A multicomponent study of Pb and Cu retention was performed using a selective contamination technique. Soil components were selectively extracted from a multicomponent illite clay artificial soil using extractants commonly utilized in sequential extraction studies. Pb and Cu retention by the soil components: carbonates, amorphous oxides, natural organic matter and the clay minerals, were examined. It was found that the clay minerals are the most important contributor to the retention of Pb and Cu, which in this case is predominantly illite. Adsorption and not precipitation is believed to be the controlling mechanism of retention although retention by precipitation increased with increasing pH. / Pb and Cu retention from a single metal solution as well as competitive retention of Pb and Cu from a mixed metal solution on each of the untreated and treated artificial soils were examined. Competitive adsorption experiments found that Pb was preferred over Cu for adsorption by the untreated and treated artificial soils and greater quantities of Pb were retained than Pb applied in composite with Cu or Cu applied as a single metal. Pb removed from the artificial soil, using sequential extraction analysis, was compared to Pb retained and mass balance was observed. / The artificial soil was found to contain both variable and constant charge surfaces but the artificial soil contaminant interaction was modelled best using only the variable charge surface. The presence of ion exchange adsorption and Ca competition are examined.

Nondestructive evaluation of the structural integrity of shaft and tunnel concrete linings is the focus of this thesis. A nondestructive testing system was assembled based on the principle of miniature seismic reflection (MSR). The MSR system consists of spherical tip impactors and a pair of vertical and tangential displacement transducers. Mechanical impact causes generation of stress P- and S-waves in the test object. The elastic waveforms undergo multiple reflections between the top and bottom of the testing layer. The surface displacements are captured by a vertical and tangential displacement transducer. The signals are transformed from time domain waveforms to frequency spectra. The vertical displacement transducer is sensitive to normal surface displacements and the highest amplitude peak on the computed frequency spectrum is related to the resonance of the P-wave between the top and the bottom layer. Similarly, the tangential displacement transducer is sensitive to the horizontal surface displacements, and the maximum peak value in the generated frequency spectrum corresponds to the resonance of the S-wave between the two layers of the testing object. Thus, knowing the thickness of the given layer, as well as the measured frequencies, allows P- and S-wave velocities to be calculated. Alternatively, if the thickness is unknown, the time-distance graph of the primary surface wave arrivals can be used to calculate the P-wave velocities and, subsequently, the thickness of the layer. The MSR response depends on the material properties of the testing object. The elastic wave velocities can be used to calculate directly the dynamic elastic properties of the test object. In this study, simulated fractures and steel reinforcement bars were detected and located using the reflected P-waves. In addition, the changes in elastic properties of various types of concrete mixes were monitored for a 28-day curing period. The MSR elastic constants were then compared with dyn

The goal of this study is to examine the possibility of reducing the epistemic uncertainties in seismic vulnerability estimation methods, particularly when properties of simplified models utilized in these methods are fitted to those obtained, for example, from Ambient Vibration Tests (AVTs) inter alia carried out on specified buildings without much prior knowledge on their characteristics and structural details. A seismic evaluation procedure was developed that utilizes the modal parameters of buildings extracted from AVT to construct a shear buildings model of the building and uses the maximum inter-story drift due to an earthquake as the performance index. The spectral displacement at the fundamental frequency of the buildings is used as the ground motion parameter to characterize the earthquake. Seismic Vulnerability of a building is expressed as the probability of passing the threshold of 'slight damage' by considering limits on inter-story drift as defined in the HAZUS MH-MR4. The procedure was applied to twenty four medium to high rise buildings located in Downtown Montreal and a GIS software was used to generate the spatial distribution of seismic vulnerability on a map. One of the aims of this study is to reduce the time and cost of carrying out AVTs for application to a large of number of buildings. In this regard, the synchronization of data obtained in AVT is of utmost importance since the extraction of modal parameters depends on the correlation of responses between various nodes. Ensuring synchronization through hardware means is often expensive yet unreliable, especially in case of large buildings. In this study a novel data processing method is proposed to synchronize the data recorded on separate data acquisition systems. Application of this method is demonstrated by conducting AVT on Jacues Bizzard Bridge in Montreal and several buildings in Downtown Montreal. The National Building Code of Canada (NBCC 2010) requires that torsional modes be included in the dynamic analysis of buildings and that the deflection of the two points located on the periphery of the building be used for calculating the inter story drifts. Also investigated in this study are various sensor deployment schemes using a numerical model for simulation of AVT in order to determine the optimal deployment scheme that can capture torsional modes of the buildings while keeping the time and cost of the AVT at a minimum. / Le but de cette étude est d'examiner la possibilité de réduire les incertitudes épistémiques dans les méthodes d'estimation de la vulnérabilité sismique, en particulier lorsque les propriétés de modèles simplifiés utilisés dans ces méthodes sont adaptés à ceux obtenus, par exemple, des tests de vibrations ambiantes (AVT), entre autres, réalisé sur des bâtiments visés, sans trop de connaissances préalables sur leurs caractéristiques et détails structurels. Une procédure d'évaluation sismique a été développé qui utilise les paramètres modaux de bâtiments extraites de AVT pour construire un modèle des bâtiments de cisaillement de l'édifice et utilise la dérive maximale entre histoire due à un tremblement de terre que l'indice de performance. Le déplacement spectral à la fréquence fondamentale des bâtiments est utilisée comme paramètre de mouvement du sol pour caractériser le tremblement de terre. Vulnérabilité sismique d'un bâtiment est exprimée comme la probabilité de passer le seuil de «légers dommages» en tenant compte des limites à la dérive inter-histoire, tels que définis dans les HAZUS MH-MR4. La procédure a été appliquée à vingt-quatre à moyen et bâtiments de grande hauteur situé au centre-ville de Montréal et un logiciel SIG a été utilisé pour générer la distribution spatiale de la vulnérabilité sismique sur une carte.L'un des objectifs de cette étude est de réduire le temps et le coût de la réalisation AVT pour application à un grand de nombre de bâtiments. À cet égard, la synchronisation des données obtenues dans AVT est d'une importance capitale car l'extraction des paramètres modaux dépend de la corrélation des réponses entre les différents nœuds. Assurer la synchronisation par voie matérielle est souvent coûteux encore peu fiables, notamment en cas de grands bâtiments. Dans cette étude, une méthode de traitement des données roman est proposé de synchroniser les données enregistrées sur les systèmes d'acquisition de données distinctes. L'application de cette méthode est démontrée en effectuant AVT sur Jacues Bizzard pont à Montréal et plusieurs bâtiments au centre-ville de Montréal. Le Code national du bâtiment du Canada (NBCC 2010) exige que les modes de torsion être inclus dans l'analyse dynamique des bâtiments et que la déviation des deux points situés à la périphérie du bâtiment sera utilisé pour calculer les dérives inter histoire. Également étudiés dans cette étude sont différents schémas de déploiement de capteurs à l'aide d'un modèle numérique de simulation de AVT afin de déterminer le schéma de déploiement optimal qui peut capturer des modes de torsion des bâtiments tout en gardant le temps et le coût de l'AVT au minimum

This research describes an experimental and analytical investigation to evaluate the seismic performance of poorly designed and detailed reinforced concrete (RC) flexural shear walls both in their as-built conditions and after being retrofitted. Older shear walls have several deficiencies which make them vulnerable in case of moderate to severe earthquakes. Full-scale shear wall specimens were constructed and tested under reversed cyclic loading. Two different techniques were chosen to retrofit the deficient walls in order to improve the overall performance. A retrofit technique using Carbon Fibre Reinforced Polymer (CFRP), having minimum intervention, was studied to determine the seismic performance. A more labour-intensive repair technique, including the addition of a reinforced concrete jacket in the critical region (location of potential plastic hinging and lap splices of vertical bars) together with CFRP wrapping was also studied. The responses obtained from experiments were used to develop behavioural models, capable of representing the global responses of the walls, as well as critical failure modes observed in the experiments. These models provide useful tools for predicting the complete reversed cyclic loading responses of shear walls. The analytical models were used to predict the responses of a deficient prototype wall-frame structure in its original condition as well as after retrofit, subjected to different seismic hazard levels. This study enabled an evaluation of the performance of the prototype structure to determine the effectiveness of retrofit and repair measures. / Cette recherche présente une étude expérimentale et analytique pour évaluer la performance sismique des murs des contreventements déficients avant et après réhabilitation sismique. Les murs représentent la construction typicalité des 1960's et ils sont plusieurs déficiences. Les murs à grande échelle ont été construits et soumises à des charges cycliques alternées. Deux techniques différentes ont été choisies et examiné pour la réhabilitation sismique des murs déficients. Une méthode de dimensionnement de réhabilitation sismique, avec l'intervention minimale, utilisant de polymères renforcés de fibres de carbone (PRFC). La deuxième technique compris l'ajout d'une chemises en béton armé (renforcés de fibres d'acier et des armatures) dans la région critique (la région de rotule plastique potentielle et du chevauchement des armatures verticales), accompagnée PRFC pour l'amélioration résistance cisaillement de murs. Les réponses obtenues à partir d'expériences fournissent des informations importantes sur les caractéristiques des murs des contreventements qui peuvent être utilisées pour développer modèles comportementaux et calibrer des techniques de prédictions numériques. Ces modèles sont capables de représenter les réponses globales des murs. Les modèles numérique ont été utilisés pour prédire les réponses d'un vieux bâtiment (ossatures résistantes au moment munies de murs de contreventement) de cinq étages en béton armé dimensionne selon le code 1963 de l'ACI ((American Concrete Institute) et Code national du bâtiment 1965 du Canada (CNBC), et pourrait être vulnérables lors de séismes forts ou même modères. Le bâtiment est analyse (statique pushover et l'analyse dynamique de l'historique temporel) dans le régime non-linéaire avant et après réhabilitation séismique des murs.

Facades mounted on the exterior of buildings protect the interior from aggressive environments, besides contributing to their aesthetics and technical performance. Unfortunately, despite some serious facade failures involving some deaths and injuries, their inspection and maintenance, which are essential for public safety, have been generally ignored. On July 16, 2009, a large concrete facade element, weighing 320 kg, detached from the building structure of a Montreal hotel and fell on its exterior sidewalk cafe, instantaneously killing a young woman celebrating her birthday and injuring her husband. Some major U.S. cities, such as New York, Chicago and Boston have learnt from such tragedies, and nine American cities have enacted by-laws or ordnances requiring mandatory periodic facade inspections to ensure public safety. However, Canadian cities do not have similar stringent regulations to guide design, construction, maintenance and life-cycle performance of facades to ensure their safety over service life. The National Building Code of Canada (NBCC) includes safety provisions for building components which implement environmental separation; however, the NBCC and other relevant CSA standards do not deal adequately with the maintenance, performance and durability issues related to the performance of these facades. This research program is an attempt to develop and recommend strategies to minimize these risks through mandatory inspection and maintenance programs, and to eliminate similar tragedies from occurring in the future. / Façades montés sur l'extérieur de bâtiments à protéger l'intérieur d'environnements agressifs, en plus de contribuer à leur esthétique et performances techniques. Malheureusement, malgré quelques ratés façade graves impliquant des morts et des blessés, leur inspection et d'entretien, qui sont essentiels pour la sécurité du public, ont été généralement ignorée. Le 16 Juillet 2009, un élément de façade en béton grand, pesant 320 kg, détaché de la structure du bâtiment d'un hôtel de Montréal et est tombé sur son café sur le trottoir extérieur, tuant instantanément une jeune femme fête son anniversaire et blessé son mari. Certaines grandes villes américaines, comme New York, Chicago et Boston ont appris de telles tragédies, et neuf villes américaines ont adopté des lois ou des munitions qui nécessitent des inspections obligatoires périodiques façade pour assurer la sécurité du public. Toutefois, les villes canadiennes n'ont pas similaires réglementations strictes pour guider les performances conception, la construction, l'entretien et du cycle de vie des façades pour assurer leur sécurité pendant la durée de vie. Le Code national du bâtiment du Canada (CNBC) comporte des dispositions de sécurité pour les éléments de construction qui mettent en œuvre la séparation de l'environnement, mais les normes du CNB et autres pertinentes de la CSA ne traite pas de manière adéquate les questions de maintenance, de performance et de durabilité liés à l'exécution de ces façades. Ce programme de recherche est une tentative d'élaborer et de recommander des stratégies pour minimiser ces risques par l'inspection obligatoire et des programmes de maintenance, et d'éliminer les tragédies semblables ne se reproduisent à l'avenir.

This dissertation investigates a novel approach to seismic design of eccentrically braced frames. The proposed design procedure incorporates non-linear time-history analysis directly into the design process. Member forces introduced by a chosen earthquake record are monitored throughout the time history, and the frame elements are selected so that they have adequate resistances for peak forces. This process is carried out iteratively. For the earthquake records used, the proposed procedure leads to a design which achieves desired seismic behaviour, characterized by the stable elastic response of columns and braces, and with inelastic action confined primarily to links. / The procedure was implemented by means of three computer programs, two of which were developed as part of this study. The sensitivity of the procedure to initial section selection was studied and a methodology to obtain an appropriate site-specific earthquake record to use in the analysis was proposed. / The application of the procedure was illustrated through examples of three Chevron-type EBFs, these having four, eight and fourteen storeys and being located in Victoria, B.C. It was demonstrated that the proposed design method is simple and efficient, and can be used either as an alternative design method or in combination with current design practice. Analytical results indicate that frames designed using this alternative approach have improved behaviour compared to those designed in accordance with the present Canadian design requirements, in particular regarding the response of columns and braces. / In the second part of the study, the analytical tools developed were used to further investigate and enhance the understanding of seismic behaviour of EBFs. Modifications of seismic design requirements for EBFs, suitable for incorporation in the Canadian Standard for design of steel buildings, CSA/CAN-S16.1 were examined. The inelastic response of an eight-storey EBF designed following these modified requirements is compared to that of a corresponding structure designed using the iterative procedure. Attention was further directed to seismic force profiles, magnitudes of axial forces and moments for use in the design of columns, force modification factors and the relationship between inelastic inter-storey drifts and inelastic link deformations.

<p> MOVES is the current emission inventory model developed by the Environmental Protection Agency (EPA) for estimating mobile source emissions. This model is very data intensive compared to its predecessors and definitive guidance has not yet been provided for doing regional analyses. There is reliance, in many cases, on using national default data. The impact of the assumptions and pre-processing of input data have not been well studied or if they have, not well documented. New technologies and sensors now in use by many transportation agencies could be a rich source of regional data. </p><p> This research has compared the current conformity analysis for a county in Delaware and selected alternatives for five of the more significant inputs to the MOVES model. This work analyzed average speed distributions, vehicle miles travelled by road type distribution, temporal distribution of vehicle miles travelled, vehicle starts estimation, and future vehicle population and age distribution. For each input the current data and pre-processing methods were compared to an alternative based in easily obtainable data and the impact on the emissions inventory. Some of the alternative methods showed small changes on the inventory, while some provided a significant reduction. </p><p> This research will be useful to agencies that must utilize the MOVES model. It will be clear which inputs require precise, local data and which inputs where either default or simplified data is sufficient. The findings of this research could be used by EPA as guidelines for implementing the MOVES model.</p>

Much of our subsurface infrastructure suffer from aging and is becoming more susceptible to damage due to the deterioration of either the buried structure or the surrounding ground. A known mode of deterioration in tunnels is the formation of erosion voids on the outer surface of the tunnel linings. These are usually caused by the ingress of groundwater through cracks in the tunnel lining that slowly erode the soil surrounding the crack by transporting soil particles. This process may lead to pressure redistribution on the lining and progressive deterioration that could lead to eventual failure. A greater understanding of the impact of these erosion voids can aid in the maintenance of aging infrastructure. A review of the literature regarding this topic showed that little research has been done beyond numerical analysis and site investigations of failed tunnels. This study presents the results of the experimental investigation that has been conducted to examine the effect of erosion voids on the earth pressure distribution acting on the tunnel liner. The experimental setup allowed for the simulation of the two-dimensional tunnelling process and the tunnelling-induced pressure that results from shield tunnelling. A model tunnel was constructed out of segmented steel pipe to simulate a machine bored tunnel. A controlled contraction of the tunnel diameter was used to simulate a tail void closure and soil movement needed to establish initial conditions. Pressure sensors were placed at various locations along the lining and fine sand was used as the soil medium. A void of known size was then introduced at different locations around the tunnel and the contact pressure on the lining was measured before and after the void introduction. Results indicated significant changes in the magnitude of earth pressure in the close vicinity of the void. The changes in earth pressure differed greatly depending on the placeme / Notre infrastructure souterraine souffre du vieillissement et devient plus susceptible au dommage grâce à la détérioration de la structure ou la terre enveloppante. Un processus de détérioration des tunnels connu est la création de poches de vide due à l'érosion à la surface extérieure de la doublure du tunnel. Elles sont normalement créer par l'entrée de l'eau souterraine entourant la fissure en transportant des particules de terre. Ce processus pourrait mener à une redistribution de la pression interstitielle sur la doublure et une détérioration progressive qui risque de créer une rupture. Une compréhension plus importante de l'impacte de ces poches de vide peut aider dans la maintenance d'infrastructure vieillissante.Une revue de la littérature concernant ce sujet montre que peu de recherche a été faite au delà de d'analyse numérique et de l'investigation de site de tunnel. Cette étude présente les résultats de l'investigation expérimentale qui a été mené pour examiner l'effet des poches de vide sur la distribution de pression des terres actant sur la doublure du tunnel. Le montage expérimentale a permit pour la simulation du processus de tunneling en deux dimensions et de la pression induit par le tunneling qui en résulte des travaux de perçage de tunnels protecteurs. Une modèle de tunnel a été construit de tuyau d'acier segmenté pour simuler les machines TBM (Tunnel Boring Machine). Une réduction contrôlée du diamètre du tunnel a été utilisé pour simuler le tassement des machines TBM et le mouvement de terre nécessaire pour établir les conditions initiales. Des capteurs de pression ont été mit à divers emplacements le long de la doublure et de la terre fine a été utilisé en temps que sols. Des poches de vide de taille connue ont été ensuite introduites aux différents emplacements autour du tunnel et la pression sur la doublure a été mesurée a

As Canadian municipalities venture into rehabilitation and replacement of extensively deteriorated underground water distribution and sewerage assets, municipal decision-makers, engineering and construction research bodies and the public all feel that this type of construction work can have adverse effects on the society. This thesis reviews these negative impacts which include, but are not limited to damage of nearby buried and above-ground infrastructure, disruption of traffic, loss of accessibility to businesses, health hazards to workers and the public, and finally environmental pollution and damage. There is presently no accepted practice-oriented method for the evaluation of these social, economic and environmental impacts. This research project proposes a framework to enable municipalities, utility agencies and contracting firms to quantitatively estimate the total cost to society of buried municipal infrastructure renewal projects using open trench, or trenchless construction methods. The total cost of a project is the sum of all the direct and indirect costs borne by the client organization, and external costs borne by society. The external costs can be separated into three components: social, economic and environmental costs. Use of the proposed methodology in a case study of a water main rehabilitation project using trenchless technologies in the city of Montreal, Canada, revealed that the indirect and external costs of the project were approximately 25 percent of its direct costs. The most significant cost components were those attributable to increased vehicular travel time and lost business income. / Les municipalités canadiennes s'apprêtent à implanter de grands programmes de réhabilitions et de remplacements des systèmes d'aqueducs et égouts gravement détériorés. Les ingénieurs, entrepreneurs, centres de recherches en génie civil, ainsi que le public affirment que ces travaux ont des impacts négatifs sur la société. Ce mémoire fait état de ces impacts qui incluent, entre autres, l'endommagement des infrastructures avoisinantes, le dérangement de la circulation, la perte d'accessibilité aux entreprises, les risques en santé chez le public et les ouvriers, mais aussi la pollution et l'endommagement environnemental. Présentement, en pratique, il n'y a aucune méthode pour évaluer ces impacts sociaux, économiques et environnementaux. Ce projet de recherche propose aux municipa lités, aux fournisseurs de systèmes public et aux entrepreneurs un procédé pour quantifier le coût total à la société, attribuable à des projets de renouvellement des infrastructures-souterraines par les méthodes de tranchée ouverte ou sans-tranchée. Le coût total d'un projet est la somme des coûts directement et indirectement assumés par le client, ainsi que les coûts externes assumés par les membres de la société. Les coûts externes peuvent être séparés en trois catégories : les coûts sociaux, économiques et environnementaux. Dans le cadre de ce projet, une évaluation du coût total d'un projet de réhabilitation d'aqueduc par technique sans-tranchée à Montréal a conclu que les coûts indirects et externes montaient à 25 pour cent des coûts directs considérés dans le contrat. Les délais aux usagers routiers et la réduction des chiffres d'affaires des entreprises étaient attribuables aux deux plus grands coûts sociaux, économiques et environnementaux.

This thesis deals with vibration frequency evaluation using non-destructive modal testing of beam-type structures. The current state of Canada's bridges is reviewed for its present condition and urgent needs. The basic modes of deterioration in concrete bridges, namely, corrosion of reinforcing steel and freezing and thawing cycles were also reviewed. Bridge inspection fundamentals are discussed summarily. In addition, a summary of the available research on modal testing is presented. Five reinforced concrete beams were tested in this preliminary research program to study the effect of progressive cracking at increasing load levels on the changes in their natural frequencies. Analysis of the results shows that the natural frequency is related to the changes in the structural stiffness of the beam, and the level of damage. The results from this preliminary investigation show that vibration testing is a useful tool for studying the existing health of a structural system. / L'auteur présente une étude préliminaire de la faisabilité d'utiliser des techniques d'analyse modale dans les poutres en béton armé comme méthode non-destructive d'évaluation de leur résistance.Un survol de l'état de détérioration des ponts au Canada permet d'abord d'établir les besoins les plus urgents. La thèse résume ensuite l'état des connaissances sur les modes de détérioration les plus communs dans les ponts en béton, soit la corrosion des aciers d'armature et les effets cycliques des conditions saisonnières de gel et dégel. Un résumé des étapes de base de l'inspection des ponts est également suivi d'une revue sommaire de la recherche sur les méthodes d'analyse modale.L'aspect expérimental de la recherche comprend des tests de mesures modales sur cinq spécimens de poutres en béton armé afin d'évaluer les variations de la fréquence naturelles des spécimens en fonction de leur état de fissuration induite par des surcharges. L'analyse des résultats indique clairement que la fréquence naturelle est réduite par les changements de rigidité des poutres selon le niveau d'endommagement. Les résultats de cette étude préliminaire indiquent que les méthodes vibrationnelles sont utiles pour évaluer la condition structurale des composants.