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A series of relatively recent bridge failures due to pier scour, as reported in literature, has rekindled interest in furthering our understanding of the scour process and for developing improved ways of protecting bridges against scour. Moreover, increased attention is being given to the state of Canadas infrastructure, a major aspect of which is the transportation network. In part, there is concern about both the impact of a failure on the handling of traffic flow while the failure is being remedied and on the cost of replacing the failed system component. As such, attention is being given to the scour design of new bridges and to the inspection, maintenance and management of existing bridge structures. The two major countermeasure techniques employed for preventing or minimising local scour at bridge piers are increased scour resistance and flow alteration. In the former case, the objective is to combat the erosive action of the scour-inducing mechanisms using hard engineering materials or physical barriers such as rock riprap. In the latter case, the objective is to either inhibit the formation of the scour-inducing mechanisms or to cause the scour to be shifted away from the immediate vicinity of the pier. This research focuses on a particular application of the latter technique. <p> In this study, the use of collars for reducing the effects of local scour at a bridge pier is presented together with the time aspect of the scour development. The adoption of a collar is based on the concept that its existence will sufficiently inhibit and/or deflect the local scour mechanisms so as to reduce the local scour immediately adjacent to the pier. The overall objective of the research is to study the temporal development of the scour for a pier fitted with a collar and a pier without a collar. More specifically, the objectives are: i) to evaluate the effectiveness of a pier collar for mitigating the depth of scour that would otherwise occur at a bridge pier; and ii) to assess the occurrence of an equilibrium scour condition, if achieved, or of the implications of not achieving such a condition in respect of interpreting the results obtained from a physical hydraulic model study. <p>The study was conducted using a physical hydraulic model operated under clear-water conditions in cohesionless bed material. Tests were conducted using two different pier diameters so as to determine the effect of pier diameter on the temporal development of scour for a plain pier. Also investigated was the effect of collar size on the time development of scour and its efficacy at preventing scour at a bridge pier. The time development of the scour hole around the model pier with and without a collar installed was compared with similar studies on bridge piers. Several equations for the temporal development of scour depth and those for the prediction of the equilibrium scour depth were tested as part of this study. <p>The results of the model study indicated that the maximum depth of scour is highly dependent on the experimental duration. The depth of the scour hole increases as the duration of the increased flow that initiates the scour increases. The extent of scour observed at the pier also increases as the duration of the tests increases. It was found that the temporal development of the scour hole at the pier was dependent on whether or not the pier was fitted with a collar placed at the bed level. The pathway to an equilibrium scour depth is different depending on whether the pier is fitted with a collar or not. With a collar in place, the development of the scour hole is considerably delayed. A truly equilibrium scour condition is not readily attainable and was not achieved in the work reported herein. It was demonstrated that wrong conclusions may be reached if a test is stopped short of an equilibrium state. As regards the temporal development of scour depth and for the tests in which no collar was fitted to the pier, it was noted that the form of equation that fits the experimental data well was the one given by Franzetti et al. (1982). Furthermore, it is possible to reach a variety of conclusions about the efficacy of using collars as a pier scour countermeasure technique, depending on which definition of time to equilibrium scour is adopted.

Caisson or pier foundations are encountered as part of the foundation system of tall structures such as bridges, transmission towers, heliostats, etc, and correspond to rigid blocks of length-to-diameter (D/B) ratio on the order of D/B = 2-6. As a result of their geometry and stiffness characteristics, the mechanisms of load transfer from the superstructure to the surrounding soil and their kinematic response to seismic wave propagation are governed by a complex stress distribution at the pier-soil interface, which cannot be adequately represented by means of simplified Winkler models for shallow foundations or flexible piles. Continuum model solutions, such as 3D finite elements (FE) cannot be employed frequently in practice for the design of non-critical facilities due to the cost and effort associated with these analyses. The objective of this work is to develop a Winkler-type model for the analysis of transversely-loaded caissons, which approximately accounts for all the main soil resistance mechanisms mobilized, while retaining the advantages of simplified methodologies for design at intermediate levels of target accuracy. Investigation of the governing load-transfer mechanisms and development of complex spring functions is formulated on the basis of 3D FE simulations. Initially, the soil-structure stiffness matrix is computed by subjecting the pier to transverse static and dynamic loading at the top, and numerically estimating the response. Complex frequency-dependent functions are next developed for the spring constants by equating the stiffness matrix terms to the analytical expressions developed for the four-spring model. Sensitivity analyses are conducted for optimization of the truncated numerical domain size, finite element size and far-field dynamic boundary conditions to avoid spurious wave reflections. Simulations are next conducted to evaluate the transient response of the foundation subjected to vertically propagating shear waves, and results are compared to the response predicted by means of the 4-spring model. Finally, the applicability of the method is assessed for soil profiles with depth-varying properties. While the methodology developed is applicable for linear elastic media with no material damping, the expressions of complex spring functions may be extended to include hysteretic damping, nonlinear soil behavior and soil-foundation interface separation, as shown in the conclusions.

Condition assessment of existing concrete bridge pier caps using the general shear provisions of the AASHTO LRFD Bridge Design Specification has caused the Georgia Department of Transportation (GDOT) to post a large number of bridges in the State of Georgia. Posting of bridges disrupts the free flow of goods within the region served by the bridge and has a negative economic impact. To prevent structural deterioration, diagonal cracking or failure of concrete pier caps in shear, the GDOT employs an in-situ strengthening technique that utilizes an external vertical post-tensioning system. However, the fundamental mechanics of this system and its effectiveness under service load have not been examined previously. This research examines the behavior of reinforced concrete pier caps that utilize the above strengthening system in a combined analytical and experimental program. In the experimental part of the study, two groups of full-scale reinforced concrete deep beam specimens were tested. The first group consisted of six deep beams with shear span/depth ratios of approximately 1.0, which is typical of bridge pier caps; of these six, two included the external post-tensioning system. In the second group, nine deep beam specimens that included a segment of the column representing the pier were tested; four of those tests included the external post-tensioning system. The tests revealed that the shear capacity computed using the AASHTO LRFD Bridge Design Specifications provided a conservative estimate of the specimen capacity in all but one case when compared to the experimental results. However, the AASHTO strut and tie provisions were found to provide a much closer assessment of the load carrying mechanism in the pier cap than the general shear provisions, in that they were able to predict the load at which yielding of the tension reinforcement occurred as well as the angle of the compression strut. The presence of the column segment in the second group had a significant impact on the failure mechanism developed in the specimen near ultimate load. The stress concentration at the reentrant corner between the pier cap and column interface served as an attractor for the formation of diagonal shear cracks, a mechanism not observed in previous deep beam tests in shear. The research has led to recommendations for improving the design of pier caps and the external post-tensioning system, where required, based on mechanics which are consistent with the results of the experimental program.

The shear capacity of reinforced concrete pier caps in existing bridge support systems can be a factor which limits the capacity of an existing bridge. In their usual configuration, pier caps behave as deep beams and have the ability to carry load through tied arch action after the formation of diagonal cracks. Externally bonded fiber reinforced polymer (FRP) reinforcement has been shown to increase the shear capacity of reinforced concrete members which carry load through beam action. However, there is an insufficient amount of research to make it a viable strengthening system for beams which carry load through arch action, such as pier caps. Accordingly, this research was aimed at investigating the behavior of reinforced concrete pier caps through a coordinated experimental and analytical program and to recommend an external strengthening method for pier caps with perceived deficiencies in shear strength. The experimental study was performed on laboratory specimens based on an existing bridge in Georgia. A number of factors were examined, including size, percentage longitudinal reinforcement and crack control reinforcement. The results showed that increasing the longitudinal tension reinforcement increased the beam capacity by changing the shape of the tied arch. In contrast, the presence of crack control reinforcement did not change the point at which diagonal cracking occurred, but it did increase the ultimate capacity by reinforcing the concrete against splitting. The results of the experimental study were used in conjunction with a larger database to examine different analytical methods for estimating the ultimate capacity of deep beams, and a new method was developed for the design of external strengthening. Two specimens were tested with externally bonded FRP reinforcement applied longitudinally to increase the strength of the tension tie. The test results correlated well with the proposed method of analysis and showed that increasing the strength of the longitudinal tension tie is an effective way to increase the strength of a reinforced concrete deep beam.

L`Inde a constitué un lieu de voyage pour beaucoup d`écrivains occidentaux, en particulier, pendant les années 60-70, pour cinq intelllectuels éuropéens et americains, qui ont voyagé et écrit différents textes. Pasolini, Moravia, Paz, Ginsberg et Duras ont parlé de l`Inde en utilisant différents languages pour décrire leur réncontre avec l`Autre au délà des catégories binaires occidentales. / India in the 60 and 70 has been the destination of the journey of five European and American writers who have stayed and wrote about it. Pasolini, Moravia, Ginsberg, Paz and Duras wrote of India using different languages from the travel documents, to the notes, to the essay, to the diaries up to the cinematic language. They described their encounter with the Other trying to go over the exotic stereotypes of western discourse into a space opaque and fragmented. / L’India ha costituito negli anni sessanta e settanta la destinazione dela viaggio di cinque scrittori europei e american che vi hanno soggiornato e ne hanno scritto. Pasolini, Moravia, Ginsberg, Paz e Duras hanno scritto dell’India e sull’India usando linguaggi diversi che vanno dal racconto di viaggio agli appunti al diario al saggio fino ad arrivare al linguaggio cinematografico. Attraverso questi multiformi linguaggi essi descrivono il loro incontro con l’Altro andando al di là dello stereotipo e delle categorie binarie del pensiero occidentale, captando l’Altro attraverso un discorso che diventa opaco e frammentario.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal / Pour respecter les droits d'auteur, la version électronique de cette thèse ou ce mémoire a été dépouillée, le cas échéant, de ses documents visuels et audio-visuels. La version intégrale de la thèse ou du mémoire a été déposée au Service de la gestion des documents et des archives de l'Université de Montréal.

Le sentiment de l'Histoire dans l'oeuvre de Pier Paolo Pasolini : une poétique en prise avec le temps. Pier Paolo Pasolini a entretenu des rapports complexes et chaotiques avec l'Histoire. C'est à partir d'un texte intitulé Le sentiment de l'histoire dont il est l'auteur que notre travail de recherche est né. C'est ce rapport qu'il s'agira de comprendre, car, nous semble-t-il, c'est de ce corps à corps avec l'histoire que se love la production artistique du cinéaste. En découpant le corpus pasolinien en trois grands axes, nous verrons d'abord comment son sentiment de l'histoire est vécu sous le mode d'un retour à un temps pré-historique ; puis comment l'antique vient hanter le contemporain et enfin comment " il dopo storia " ce temps dénoncé par Pier Paolo Pasolini dès la moitié des années soixante a effacé tous les spectres du passé, provoquant ainsi l'homologation la plus atroce : celle des corps et des chairs, modifiant par là même notre rapport à la réalité. Pasolini serait alors l'ange de l'histoire (Angelus Novus) si bien décrit par Walter Benjamin, annonçant avec une exactitude glaçante ce que le XXIème siècle est devenu. Un ange qui agit à la fois pour son temps et contre son temps afin de permettre l'émergence des spectres de l'histoire pour reprendre le vocabulaire de Walter Benjamin. Ces figures fantomatiques, ces lucioles pasolinniennes survivent dans notre présent et permettent ainsi de construire un agir politique en faveur de notre temps : voilà sans doute l'héritage que nous a laissé Pasolini.

Diss. Univ. Zürich, 2007. / Zugl. Diss., Univ. Zürich, 2007. Bibliographie: 243-258.

Η παρούσα εργασία κινείται σε δύο θεματικούς άξονες που συγκλίνουν σε έναν κοινό παρονομαστή: στον μύθο του Οιδίποδα. Στο πρώτο μέρος αναλύεται ο τρόπος με τον οποίο ο μύθος αυτός και το παράγωγό του οιδιπόδειο σύμπλεγμα αποτέλεσαν την αφορμή και το πρωτογενές υλικό στην σύσταση της ψυχαναλυτικής θεωρίας της λογοτεχνίας, παρουσιάζοντας διεξοδικά τις απόψεις των κυριότερων θεωρητικών της, αλλά και αναλύοντας ένα πολύτιμο φροϋδικό δοκίμιο που εφαρμόζει τους καρπούς της στον ήρωα – αρχέτυπο του ελισαβετιανού θεάτρου, στον Άμλετ του William Shakespeare. Στο δεύτερο μέρος, αφού παρουσιαστεί ο πρωτογενής μύθος και ερευνηθούν οι καταβολές του, επιχειρείται μία βαθύτερη προσέγγιση στην πρόσληψή του στην νεότερη δραματουργία και τον κινηματογράφο, αναλύοντας την Καταχθόνια Μηχανή του Γάλλου Jean Cocteau και το κινηματογραφικό έργο Οιδίπους Τύραννος του Ιταλού Pier Paolo Pasolini, έργα που έχουν προφανή συνάφεια με τις φροϋδικές προεκτάσεις του οιδιπόδειου μύθου. / The present thesis moves in two themes with a common parameter: Oedipus myth. The first part refers to the way in which this myth and its product, Oedipus’ complex, have been the motive and the primal material for the construction of the psychoanalytic theory of literature, extensively presenting the views of its most important theoreticians, but also analyzing a precious Freudian essay which puts in practice its outcomes on the archetype-hero of the Elizabethan theater, Shakespeare’s Hamlet. In the second part, after presenting the primal myth and investigating its origins, we will penetrate into its perception in recent dramaturgy and in the cinema analyzing ‘The sinister machine’ of the French Jean Cocteau and the film Oedipus Tyrant by the Italian Pier Paolo Pasolini, which both have an obvious relevance with the Freudian extensions of the Oedipus myth.